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Versions: 00 01                                                         
Network Working Group                                         Rob Weltman
INTERNET-DRAFT                              Netscape Communications Corp.
                                                                Tim Howes
                                            Netscape Communications Corp.
                                                               Mark Smith
                                            Netscape Communications Corp.
                                                       September 26, 1997


              The Java LDAP Application Program Interface
                  draft-ietf-asid-ldap-java-api-01.txt


Status of this Memo

This document is an Internet-Draft.  Internet-Drafts are working docu-
ments of the Internet Engineering Task Force (IETF), its areas, and its
working groups.  Note that other groups may also distribute working
documents as Internet-Drafts.

Internet-Drafts are draft documents valid for a maximum of six months
and may be updated, replaced, or obsoleted by other documents at any
time.  It is inappropriate to use Internet-Drafts as reference material
or to cite them other than as ``work in progress.''

To learn the current status of any Internet-Draft, please check the
``1id-abstracts.txt'' listing contained in the Internet-Drafts Shadow
Directories on ds.internic.net (US East Coast), nic.nordu.net (Europe),
ftp.isi.edu (US West Coast), or munnari.oz.au (Pacific Rim).

Abstract

This document defines a java language application program interface to
the lightweight directory access protocol (LDAP), in the form of a class
library. It complements but does not replace RFC 1823 ([9]), which
describes a C language application program interface. It updates and
replaces draft-ietf-asid-ldap-java-api-00.txt [13], in adding clarifica-
tion on behavior under various circumstances, and in revising support
for language-sensitive attribute parsing. Other additions and correc-
tions are listed in the appendix.


1.  Introduction

The LDAP class library is designed to provide powerful, yet simple,
access to a LDAP directory services.  It defines a synchronous interface
to LDAP, with support for partial results on searching, to suit a wide
variety of applications. This document gives a brief overview of the



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LDAP model, then an overview of the constituents of the class library.
The public class methods are described in detail, followed by an appen-
dix that provides some example code demonstrating the use of the
classes, and an appendix listing changes from earlier drafts.

2.  Overview of the LDAP model

LDAP is the lightweight directory access protocol, described in [2] and
[7]. It defines a lightweight access mechanism in which clients send
requests to and receive responses from LDAP servers.

The LDAP information model comes from X.500 [1] and is based on the
entry, which contains information about some object (e.g., a person).
Entries are composed of attributes, which have a type and one or more
values. Each attribute has a syntax that determines what kinds of values
are allowed in the attribute (e.g., ASCII characters, a jpeg photograph,
etc.) and how those values behave during directory operations (e.g., is
case significant during comparisons).

Entries may be organized in a tree structure, usually based on politi-
cal, geographical, and organizational boundaries. Other structures are
possible, including a flat namespace. Each entry is uniquely named rela-
tive to its sibling entries by its relative distinguished name (RDN)
consisting of one or more distinguished attribute values from the entry.
At most one value from each attribute may be used in the RDN. For exam-
ple, the entry for the person Babs Jensen might be named with the "Bar-
bara Jensen" value from the commonName attribute.

A globally unique name for an entry, called a distinguished name or DN,
is constructed by concatenating the sequence of RDNs from the entry up
to the root of the tree. For example, if Babs worked for the University
of Michigan, the DN of her U-M entry might be "cn=Barbara Jensen,
o=University of Michigan, c=US". The DN format used by LDAP is defined
in [4].

Operations are provided to authenticate, search for and retrieve infor-
mation, modify information, and add and delete entries from the tree.

An LDAP server may return referrals if it cannot completely service a
request (for example if the request specifies a directory base outside
of the tree managed by the server). The LDAP class library offers the
programmer two options: the programmer can catch these referrals as
exceptions and explicitly issue new requests to the referred-to servers,
or the programmer can let the library automatically follow the refer-
rals.  In the latter case, the programmer may also provide a reauthenti-
cation object, allowing automatic referrals to proceed with appropriate
credentials (as opposed to anonymous authentication) for each referred-
to server.



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Before the client encodes and sends a string value to a server, the
string values are converted from the java 16-bit Unicode format to UTF-8
format. Then, when the values are received by the server, the values are
converted back to 16-bit Unicodeformat.  The integrity of double-byte
and other non-ASCII character sets is fully preserved.

The next sections give an overview of how the class library is used and
detailed descriptions of the LDAP class methods that implement all of
these functions.

3.  Overview of the LDAP classes

The central LDAP class is LDAPConnection. It provides methods to estab-
lish an authenticated or anonymous connection to an LDAP server, as well
as methods to search for, modify, compare, and delete entries in the
directory.

The LDAPConnection class also provides fields for storing settings that
are specific to the LDAP session (such as limits on the number of
results returned or timeout limits). An LDAPConnection object can be
cloned, allowing objects to share a single network connection but use
different settings (using LDAPConnection.setOption()).

To support extensions of the LDAP protocol LDAPConnection and to add the
capability to determine the LDAP protocol level supported by an LDAPCon-
nection object, LDAPConnection implements a protocol interface, which is
currently LDAPv3.

A search conducted by an LDAPConnection object returns results in an
LDAPSearchResults object, which can be enumerated to access the entries
found. Each entry (represented by an LDAPEntry object) provides access
to the attributes (represented by LDAPAttribute objects) returned for
that entry. Each attribute can produce the values found as byte arrays
or as Strings.


3.1.  Interfaces


LDAPEntryComparator   An interface to support arbitrary sorting algo-
                      rithms for entries returned by a search operation.
                      The basic java LDAP classes include one implemen-
                      tation: LDAPCompareAttrNames, to sort in ascending
                      order based on one or more attribute names.


LDAPRebind            A programmer desiring reauthentication on automat-
                      ically following referrals must implement this



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                      interface. Without it, automatically followed
                      referrals will use anonymous authentication.
                      Referrals of any type other to an LDAP server
                      (i.e. a referral URL other than ldap://something)
                      are ignored on automatic referral following.


LDAPSocketFactory     Programmers needing to provide or use specialized
                      socket connections, including Transport Layer
                      Security (TLS) based ones, can provide an object
                      constructor to implement them using this inter-
                      face.


LDAPv2                This interface defines the functionality of the
                      LDAP version 2 protocol. It is implemented by
                      LDAPConnection.


LDAPv3                This interface extends LDAPv2, adding the func-
                      tionality of the LDAP version 3 protocol. It is
                      implemented by LDAPConnection.


3.2.  Classes


LDAPAttribute         Represents the name and values of one attribute of
                      a directory entry.


LDAPAttributeSet      A collection of LDAPAttributes.


LDAPCompareAttrNames  An implementation of LDAPEntryComparator, to sup-
                      port sorting of search results by one or more
                      attributes.


LDAPConnection        Implements LDAPv3 and is the central point for
                      interactions with a directory.


LDAPControl           Sets additional parameters or constraints for an
                      LDAP operation, either on the server or on the
                      client.





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LDAPDN                A utility class to facilitate composition and
                      decomposition of distinguished names (DNs).


LDAPEntry             Represents a single entry in a directory.


LDAPExtendedOperation Encapsulates the ID and data associated with the
                      sending or receiving of an extended operation (an
                      LDAPv3 feature).


LDAPModification      A single add/delete/replace operation to an
                      LDAPAttribute.


LDAPModificationSet   A collection of LDAPModifications


LDAPRebindAuth        An implementation of LDAPRebind must be able to
                      provide an LDAPRebindAuth at the time of a refer-
                      ral. The class encapsulates reauthentication
                      credentials.


LDAPSearchConstraints Defines the options controlling search operations.


LDAPSearchResults     The enumerable results of a search operation.


LDAPSortKey           Specifies how search results are to be sorted.


LDAPUrl               Encapsulates parameters of an LDAP Url query, as
                      defined in [8].


3.3.  Exceptions


LDAPException         General exception, which includes an error message
                      and an LDAP error code.


LDAPReferralException Derived from LDAPException and contains a list of
                      LDAPUrls corresponding to referrals received on an
                      LDAP operation.



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4.  Overview of LDAP API use

An application generally uses the LDAP API in four steps.

-    Construct an LDAPConnection.  Initialize an LDAP session with a
     directory server. The LDAPConnection.connect() call establishes a
     handle to the session, allowing multiple sessions to be open at
     once, on different instances of LDAPConnection.

-    Authenticate to the LDAP server with LDAPConnection.authenticate().

-    Perform some LDAP operations and obtain some results.
     LDAPConnection.search() returns an LDAPSearchResults, which can be
     enumerated to access all entries found. LDAPConnection.read()
     returns a single entry.

-    Close the connection. The LDAPConnection.disconnect() call closes
     the connection.

All operations are synchronous - they do not return until the operation
has completed. In the java environment, it is appropriate to create a
thread for the operation rather than providing parallel synchronous and
asynchronous operations, as is the case in the C language API described
in [9]. To facilitate user feedback during searches, intermediate search
results can be obtained before the entire search operation is completed
by specifying the number of entries to return at a time.

Standard java Enumerations are used to parse search results. Errors
result in the throwing of an LDAPException, with a specific error code
and context-specific textual information available.

The following sections describe the LDAP classes in more detail.

5.  The java LDAP classes


5.1.  public class LDAPAttribute

The LDAPAttribute class represents the name and values of an attribute.
It is used to specify an attribute to be added to, deleted from, or
modified in a Directory entry. It is also returned on a search of a
Directory.


5.1.1.  Constructors

   public LDAPAttribute(String attrName)




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   Constructs an attribute with no values.


   public LDAPAttribute(String attrName,
                        byte attrBytes[])

   Constructs an attribute with a byte-formatted value.


   public LDAPAttribute(String attrName,
                        String attrString)

   Constructs an attribute that has a single string value.


   public LDAPAttribute(String attrName,
                        String attrStrings[])

   Constructs an attribute that has an array of string values.

   Parameters are:

   attrName        Name of the attribute.

   attrBytes       Value of the attribute as raw bytes.

   attrString      Value of the attribute as a String.

   attrStrings     Array of values as Strings.

   attrBytesArray  Array of values as raw byte arrays.


5.1.2.  addValue

   public synchronized void addValue(String attrString)

   Adds a string value to the attribute.


   public synchronized void addValue(byte attrBytes[])

   Adds a byte[]-formatted value to the attribute.

   Parameters are:

   attrString      Value of the attribute as a String.




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   attrBytes       Value of the attribute as raw bytes.


5.1.3.  getByteValues

   public Enumeration getByteValues()

   Returns an enumerator for the values of the attribute in byte[] for-
   mat.


5.1.4.  getStringValues

   public Enumeration getStringValues()

   Returns an enumerator for the string values of an attribute.


5.1.5.  getName

   public String getName()

   Returns the name of the attribute.


5.1.6.  removeValue

   public synchronized void removeValue(String attrString)

   Removes a string value from the attribute.


   public synchronized void removeValue(byte attrValue[])

   Removes a byte[]-formatted value from the attribute.

   Parameters are:

   attrString      Value of the attribute as a String.

   attrBytes       Value of the attribute as raw bytes.


5.1.7.  size

   public int size()

   Returns the number of values of the attribute.



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5.2.  public class LDAPAttributeSet

An LDAPAttributeSet is a collection of LDAPAttributes, as returned in an
entry on a search or read operation, or used to construct an entry to be
added to a directory.


5.2.1.  Constructors

   public LDAPAttributeSet()

   Constructs a new set of attributes. This set is initially empty.


5.2.2.  add

   public synchronized void add(LDAPAttribute attr)

   Adds the specified attribute to this attribute set.

   Parameters are:

   attr            Attribute to add to this set.


5.2.3.  elementAt

   public LDAPAttribute elementAt(int index)
                               throws ArrayIndexOutOfBoundsException

   Returns the attribute at the position specified by the index.  The
   index is 0-based.

   Parameters are:

   index           Index of the attribute to get.


5.2.4.  getAttribute

   public LDAPAttribute[] getAttribute(String attrName)

   Returns the attribute matching the specified attrName. For example,
   getAttribute("cn") returns only the "cn" attribute;
   getAttribute("cn;lang-en") returns only the "cn;lang-en" attribute.
   In both cases, null is returned if there is no exact match to the
   specified attrName.




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   public LDAPAttribute[] getAttribute(String attrName, String lang)

   Returns a single best-match attribute, or none if no match is avail-
   able in the entry.

   LDAP version 3 allows adding a subtype specification to an attribute
   name. "cn;lang-ja", for example, indicates a Japanese language sub-
   type of the "cn" attribute. "cn;lang-ja-JP-kanji" may be a subtype of
   "cn;lang-ja". This feature may be used to provide multiple localiza-
   tions in the same Directory. For attributes which do not vary among
   localizations, only the base attribute may be stored, whereas for
   others there may be varying degrees of specialization.

   getAttribute(attrName,lang) returns the subtype that matches attrName
   and that best matches lang. If there are subtypes other than "lang"
   subtypes included in attrName, e.g. "cn;binary", only attributes with
   all of those subtypes are returned. If lang is null or empty, the
   method behaves as getAttribute(attrName). If there are no matching
   attributes, null is returned.

   Example:
      Assume the entry contains only the following attributes:
         cn;lang-en
         cn;lang-ja-JP-kanji
         sn
      getAttribute( "cn" ) returns null.
      getAttribute( "sn" ) returns the "sn" attribute.
      getAttribute( "cn", "lang-en-us" ) returns the "cn;lang-en" attribute.
      getAttribute( "cn", "lang-en" ) returns the "cn;lang-en" attribute.
      getAttribute( "cn", "lang-ja" ) returns null.
      getAttribute( "sn", "lang-en" ) returns the "sn" attribute.

   Parameters are:

   attrName        The name of an attribute to retrieve, with or without
                   subtype specification(s). "cn", "cn;phonetic", and
                   "cn;binary" are valid attribute names.

   lang            A language specification as in [14], with optional
                   subtypes appended using "-" as separator. "lang-en",
                   "lang-en-us", "lang-ja", and "lang-ja-JP-kanji" are
                   valid language specification.


5.2.5.  getAttributes

   public Enumeration getAttributes()




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   Returns an enumeration of the attributes in this attribute set.

5.2.6.  remove

   public synchronized void remove(String name)

   Removes the specified attribute from the set. If the attribute is not
   a member of the set, nothing happens.

   Parameters are:

   name            Name of the attribute to remove from this set. To
                   remove an LDAPAttribute by object, the
                   LDAPAttribute.getName method can be used:

                   LDAPAttributeSet.remove( attr.getName() );


5.2.7.  removeElementAt

   public void removeElementAt(int index)
                               throws ArrayIndexOutOfBoundsException

   Removes the attribute at the position specified by the index.  The
   index is 0-based.

   Parameters are:

   index           Index of the attribute to remove.


5.2.8.  size

   public int size()

   Returns the number of attributes in this set.


5.3.  public class LDAPCompareAttrNames implements LDAPEntryComparator

An object of this class supports sorting search results by attribute
name, in ascending or descending order.


5.3.1.  Constructors

   public LDAPCompareAttrNames(String attrName)




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   Constructs an object that will sort results by a single attribute, in
   ascending order.


   public LDAPCompareAttrNames(String attrName,
                               boolean ascendingFlag)

   Constructs an object that will sort results by a single attribute, in
   either ascending or descending order.


   public LDAPCompareAttrNames(String[] attrNames)

   Constructs an object that will sort by one or more attributes, in the
   order provided, in ascending order.


   public LDAPCompareAttrNames(String[] attrNames,
                               boolean[] ascendingFlags)
                               throws LDAPException

   Constructs an object that will sort by one or more attributes, in the
   order provided, in either ascending or descending order for each
   attribute.

   Parameters are:

   attrName        Name of an attribute to sort by.

   attrNames       Array of names of attributes to sort by.

   ascendingFlag   true to sort in ascending order, false for descending
                   order.

   ascendingFlags  Array of flags, one for each attrName, where each one
                   is true to sort in ascending order, false for des-
                   cending order. An LDAPException is thrown if the
                   length of ascendingFlags is not greater than or equal
                   to the length of attrNames.


5.3.2.  isGreater

   public boolean isGreater (LDAPEntry entry1, LDAPEntry entry2)

   Returns true if entry1 is to be considered greater than entry2, for
   the purpose of sorting, based on the attribute name or names provided
   on object construction.



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   Parameters are:

   entry1          Target entry for comparison.

   entry2          Entry to be compared to.


5.4.  public class LDAPConnection implements LDAPv3, Cloneable

LDAPConnection is the central class that encapsulates the connection to
a Directory Server through the LDAP protocol. It implements the LDAPv2
and LDAPv3 interfaces. An LDAPConnection object is not connected on con-
struction, and may only be connected to one server at one port. Multiple
threads may share this single connection, and an application may have
more than one LDAPConnection object, connected to the same or different
Directory Servers.

Besides the methods described for LDAPv2 and LDAPv3, LDAPConnection pro-
vides the following methods.

5.4.1.  Constructors

   public LDAPConnection()

   Constructs a new LDAPConnection object, which represents a connection
   to an LDAP server.

   Calling the constructor does not actually establish the connection.
   To connect to the LDAP server, use the connect method.


   public LDAPConnection(LDAPSocketFactory factory)

   Constructs a new LDAPConnection object, which will use the supplied
   class factory to construct a socket connection during
   LDAPConnection.connect().

   Parameters are:

   factory         An object capable of producing a Socket.


5.4.2.  clone

   public LDAPConnection clone()

   Returns a copy of the object with a private context, but sharing the
   network connection if there is one. The network connection remains



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   open until all clones have disconnected or gone out of scope. Any
   connection opened after cloning is private to the object making the
   connection.


5.4.3.  getAuthenticationDN

   public String getAuthenticationDN()

   Returns the distinguished name (DN) used for authentication by this
   object.


5.4.4.  getAuthenticationPassword

   public String getAuthenticationPassword()

   Returns the password used for simple authentication by this object.


5.4.5.  getHost

   public String getHost()

   Returns the host name of the LDAP server to which the object is or
   was last connected, in the format originally specified.


5.4.6.  getPort

   public int getPort()

   Returns the port number of the LDAP server to which the object is or
   was last connected.


5.4.7.  getProperty

   public Object getProperty(String name) throws LDAPException

   Gets a property of a connection object.

   Parameters are:

   name            Name of the property to be returned.

                   The following read-only properties are available for
                   any given connection:



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      LDAP_PROPERTY_SDK             The version of this SDK, as a Float
                                    data type.


      LDAP_PROPERTY_PROTOCOL        The highest supported version of the
                                    LDAP protocol, as a Float data type.


      LDAP_PROPERTY_SECURITY        A comma-separated list of the types
                                    of authentication supported, as a
                                    String.

   Other properties may be available in particular implementations of
   the class, and used to modify operations such as search.

   An LDAPException is thrown if the requested property is not avail-
   able.

5.4.8.  getSearchConstraints

   public LDAPSearchConstraints getSearchConstraints()

   Returns the set of search constraints that apply to all searches per-
   formed through this connection (unless a different set of search con-
   straints is specified when calling the search method).

   Note that the getOption method can be used to get individual con-
   straints (rather than getting the entire set of constraints).

   Typically, the getSearchConstraints method is used to create a
   slightly different set of search constraints to apply to a particular
   search.


5.4.9.  getSocketFactory

   public static LDAPSocketFactory getSocketFactory()

   Returns the default LDAPSocketFactory used to establish a connection
   to a server.


5.4.10.  isAuthenticated

   public boolean isAthenticated()

   Indicates whether the object has authenticated to the connected LDAP
   server.



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5.4.11.  isConnected

   public boolean isConnected()

   Indicates whether the connection represented by this object is open
   at this time.


5.4.12.  read

   public static LDAPEntry read(LDAPUrl toGet) throws LDAPException

   Reads the entry specified by the LDAP URL.

   When this method is called, a new connection is created automati-
   cally, using the host and port specified in the URL. After finding
   the entry, the method closes the connection (in other words, it
   disconnects from the LDAP server).

   If the URL specifies a filter and scope, these are not used. Of the
   information specified in the URL, this method only uses the LDAP host
   name and port number, the base distinguished name (DN), and the list
   of attributes to return.

   The method returns the entry specified by the base DN.

   Parameters are:

   toGet           LDAP URL specifying the entry to read.


5.4.13.  search

   public static LDAPSearchResults search(LDAPUrl toGet) throws LDAPEx-
   ception

   Performs the search specified by the LDAP URL, returning an enumer-
   able LDAPSearchResults object.


   public static LDAPSearchResults search(LDAPUrl toGet,
                                          LDAPSearchConstraints cons)
                                          throws LDAPException

   Perfoms the search specified by the LDAP URL. This method also allows
   specifying constraints for the search (such as the maximum number of
   entries to find or the maximum time to wait for search results).




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   As part of the search constraints, a choice can be made as to whether
   to have the results delivered all at once or in smaller batches. If
   the results are to be delivered in smaller batches, each iteration
   blocks only until the next batch of results is returned.

   Parameters are:

   toGet           LDAP URL specifying the entry to read.

   cons            Constraints specific to the search.


5.4.14.  setOption

   public void setOption(int option,
                         Object value)
                         throws LDAPException

   Sets the value of the specified option for this LDAPConnection
   object.

   These options represent the default search constraints for the
   current connection. Some of these options are also propagated through
   the LDAPSearchConstraints, which can be obtained from the connection
   object with the getSearchConstraints method.

   The option that is set here applies to all subsequent searches per-
   formed through the current connection, unless it is overridden with
   an LDAPSearchConstraints at the time of search.

   To set a constraint only for a particular search, create an LDAPSear-
   chConstraints object with the new constraints and pass it to the
   LDAPConnection.search method.

   Parameters are:


   option          One of the following options:


      Option                        Type        Description


      LDAPv2.DEREF                  Integer     Specifies under what
                                                circumstances the object
                                                dereferences aliases.
                                                By default, the value of
                                                this option is



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                                                LDAPv2.DEREF_NEVER.

            Legal values for this option are:

            LDAPv2.DEREF_NEVER       Aliases are never dereferenced.


            LDAPv2.DEREF_FINDING     aliases are dereferenced when find-
                                     ing the starting point for the
                                     search (but not when searching
                                     under that starting entry).


            LDAPv2.DEREF_SEARCHING   Aliases are dereferenced when
                                     searching the entries beneath the
                                     starting point of the search (but
                                     not when finding the starting
                                     entry).


            LDAPv2.DEREF_ALWAYS      Aliases are always dereferenced
                                     (both when finding the starting
                                     point for the search and when
                                     searching under that starting
                                     entry).


      LDAPv2.SIZELIMIT              Integer     Specifies the maximum
                                                number of search results
                                                to return. If this
                                                option is set to 0,
                                                there is no maximum
                                                limit.

                                                By default, the value of
                                                this option is 1000.


      LDAPv2.TIMELIMIT              Integer     Specifies the maximum
                                                number of milliseconds
                                                to wait for results
                                                before timing out. If
                                                this option is set to 0,
                                                there is no maximum time
                                                limit. The actual granu-
                                                larity of the timeout
                                                depends on the implemen-
                                                tation.



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                                                By default, the value of
                                                this option is 0.


      LDAPv2.REFERRALS              Boolean     Specifies whether or not
                                                the client follows
                                                referrals automatically.
                                                If true, the client fol-
                                                lows referrals automati-
                                                cally.  If false, an
                                                LDAPReferralException is
                                                raised when a referral
                                                is detected.

                                                Referrals of any type
                                                other to an LDAP server
                                                (i.e. a referral URL
                                                other than
                                                ldap://something) are
                                                ignored on automatic
                                                referral following.

                                                By default, the value of
                                                this option is false.


      LDAPv2.REFERRALS_REBIND_PROC  LDAPRebind  Specifies an object that
                                                implements the LDAPRe-
                                                bind interface.  A user
                                                of the class library
                                                must define this class
                                                and the getRebindAuthen-
                                                tication method that
                                                will be used to get the
                                                distinguished name and
                                                password to use for
                                                authentication. If this
                                                value is null and REFER-
                                                RALS is true, referrals
                                                will be followed with
                                                anonymous (= no) authen-
                                                tication.

                                                By default, the value of
                                                this option is null.


      LDAPv2.REFERRALS_HOP_LIMIT     Integer    Specifies the maximum



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                                                number of referrals in a
                                                sequence that the client
                                                will follow. For exam-
                                                ple, if
                                                REFERRALS_HOP_LIMIT is
                                                5, the client will fol-
                                                low no more than 5
                                                referrals in a row when
                                                resolving a single LDAP
                                                request.

                                                The default value of
                                                this option is 10.


      LDAPv2.BATCHSIZE               Integer    Specifies the number of
                                                search results to return
                                                at a time. For example,
                                                if BATCHSIZE is 1,
                                                enumerating an LDAPSear-
                                                chResults will block
                                                only until one entry is
                                                available. If it is 0,
                                                enumerating will block
                                                until all entries have
                                                been retrieved from the
                                                server.

                                                The default value of
                                                this option is 1.


   value           The value to assign to the option. The value must be
                   the java.lang object wrapper for the appropriate
                   parameter (e.g. boolean->Boolean, int->Integer) .


5.4.15.  setProperty

   public void setProperty(String name, Object value) throws LDAPExcep-
   tion

   Sets a property of a connection object.

   No property names have been defined at this time, but the mechanism
   is in place in order to support revisional as well as dynamic exten-
   sions to operation modifiers.




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   Parameters are:

   name            Name of the property to set.

   value           Value to assign to the property.

                   An LDAPException is thrown if the specified property
                   is not supported.

5.4.16.  setSocketFactory

   public static void setSocketFactory(LDAPSocketFactory factory)

   Establishes the default LDAPSocketFactory used to establish a connec-
   tion to a server.

   This method is implemented as once-only. It is useful to be able to
   change the run-time connection behavior of a whole application with a
   single instruction, but the results would be confusing, and the
   side-effects dangerous, if the global default factory could be
   changed at arbitrary times by different threads. It should be called
   before the first connect(). If called (for the first time) after con-
   necting, the new factory will not be used until/unless a new connec-
   tion is attempted with the object.

   A typical usage would be:

       if (usingTLS) {
           LDAPConnection.setSocketFactory(myTLSFactory);
       }
       ...
       LDAPConnection conn = new LDAPConnection();
       conn.connect(myHost, myPort);

   In this example, connections are constructed with the default LDAP-
   SocketFactory.  At application start-up time, the default may be set
   to use a particular provided TLS socket factory.

   Parameters are:

   factory         A factory object which can construct socket connec-
                   tions for an LDAPConnection.


5.5.  public class LDAPControl implements Cloneable

An LDAPControl encapsulates optional additional parameters or con-
straints to be applied to LDAP operations. If set as a Server Control,



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it is sent to the server along with operation requests. If set as a
Client Control, it is not sent to the server, but rather interpreted
locally by the client. LDAPControl is an LDAPv3 extension, and is not
supported in an LDAPv2 environment.


5.5.1.  Constructors

   public LDAPControl(String id,
                      boolean critical,
                      byte vals[])

   Parameters are:

   id              The type of the Control, as a string.

   critical        True if the LDAP operation should be discarded if the
                   server does not support this Control.

   vals            Control-specific data.


5.5.2.  getID

   public String getID()

   Returns the identifier of the control.


5.5.3.  isCritical

   public boolean isCritical()

   Returns true if the control must be supported for an associated
   operation to be executed.


5.5.4.  getValue

   public byte[] getValue()

   Returns the control-specific data of the object.


5.6.  public class LDAPDN

A utility class representing a distinguished name (DN).




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5.6.1.  explodeDN

   public static String[] explodeDN(String dn,
                                    boolean noTypes)

   Returns the individual components of a distinguished name (DN).

   Parameters are:

   dn              Distinguished name, e.g. "cn=Babs
                   Jensen,ou=Accounting,o=Acme,c=us"

   noTypes         If true, returns only the values of the components,
                   and not the names, e.g. "Babs Jensen", "Accounting",
                   "Acme", "us" - instead of "cn=Babs Jensen",
                   "ou=Accounting", "o=Acme", and "c=us".


5.6.2.  explodeRDN

   public static String[] explodeRDN(String rdn,
                                     boolean noTypes)

   Returns the individual components of a relative distinguished name
   (RDN).

   Parameters are:

   rdn             Relative distinguished name, i.e. the left-most com-
                   ponent of a distinguished name.

   noTypes         If true, returns only the values of the components,
                   and not the names.


5.7.  public class LDAPEntry

An LDAPEntry represents a single entry in a directory, consisting of a
distinguished name (DN) and zero or more attributes. An instance of
LDAPEntry is created in order to add an entry to a Directory, and
instances are returned on a search by enumerating an LDAPSearchResults.


5.7.1.  Constructors

   public LDAPEntry()

   Constructs an empty entry.



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   public LDAPEntry(String dn)

   Constructs a new entry with the specified distinguished name and with
   an empty attribute set.


   public LDAPEntry(String dn
                    LDAPAttributeSet attrs)

   Constructs a new entry with the specified distinguished name and set
   of attributes.

   Parameters are:

   dn              The distinguished name of the new entry. The value is
                   not validated. An invalid distinguished name will
                   cause adding of the entry to a directory to fail.

   attrs           The initial set of attributes assigned to the entry.


5.7.2.  getAttribute

   public LDAPAttribute[] getAttribute(String attrName)

   Returns the attribute matching the specified attrName. For example,
   getAttribute("cn") returns only the "cn" attribute;
   getAttribute("cn;lang-en") returns only the "cn;lang-en" attribute.
   In both cases, null is returned if there is no exact match to the
   specified attrName.

   public LDAPAttribute[] getAttribute(String attrName, String lang)

   Returns a single best-match attribute, or none if no match is avail-
   able in the entry.

   LDAP version 3 allows adding a subtype specification to an attribute
   name. "cn;lang-ja", for example, indicates a Japanese language sub-
   type of the "cn" attribute. "cn;lang-ja-JP-kanji" may be a subtype of
   "cn;lang-ja". This feature may be used to provide multiple localiza-
   tions in the same Directory. For attributes which do not vary among
   localizations, only the base attribute may be stored, whereas for
   others there may be varying degrees of specialization.

   getAttribute(attrName,lang) returns the subtype that matches attrName
   and that best matches lang. If there are subtypes other than "lang"
   subtypes included in attrName, e.g. "cn;binary", only attributes with
   all of those subtypes are returned. If lang is null or empty, the



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   method behaves as getAttribute(attrName). If there are no matching
   attributes, null is returned.

   Example:
      Assume the entry contains only the following attributes:
         cn;lang-en
         cn;lang-ja-JP-kanji
         sn
      getAttribute( "cn" ) returns null.
      getAttribute( "sn" ) returns the "sn" attribute.
      getAttribute( "cn", "lang-en-us" ) returns the "cn;lang-en" attribute.
      getAttribute( "cn", "lang-en" ) returns the "cn;lang-en" attribute.
      getAttribute( "cn", "lang-ja" ) returns null.
      getAttribute( "sn", "lang-en" ) returns the "sn" attribute.

   Parameters are:

   attrName        The name of an attribute to retrieve, with or without
                   subtype specification(s). "cn", "cn;phonetic", and
                   "cn;binary" are valid attribute names.

   lang            A language specification as in [14], with optional
                   subtypes appended using "-" as separator. "lang-en",
                   "lang-en-us", "lang-ja", and "lang-ja-JP-kanji" are
                   valid language specification.


5.7.3.  getAttributeSet

   public LDAPAttributeSet getAttributeSet()

   Returns the attribute set of the entry. All base and subtype variants
   of all attributes are returned. The LDAPAttributeSet returned may be
   empty if there are no attributes in the entry.


   public LDAPAttributeSet getAttributeSet(String subtype)

   Returns an attribute set from the entry, consisting of only those
   attributes matching the specified subtype(s). This may be used to
   extract only a particular language variant subtype of each attribute,
   if it exists. "subtype" may be, for example, "lang-ja", "binary", or
   "lang-ja;phonetic". If more than one subtype is specified, separated
   with a semicolon, only those attributes with all of the named sub-
   types will be returned.  The LDAPAttributeSet returned may be empty
   if there are no matching attributes in the entry.

   Parameters are:



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   subtype         One or more subtype specification(s), separated with
                   semicolons.  "lang-ja" and "lang-en;phonetic" are
                   valid subtype specifications.


5.7.4.  getDN

   public String getDN()

   Returns the distinguished name of the entry.


5.8.  public class LDAPExtendedOperation

An LDAPExtendedOperation encapsulates an ID which uniquely identifies a
particular extended operation, known to a particular server, and the
data associated with the operation.


5.8.1.  Constructors

   public LDAPExtendedOperation(String oid,
                                byte[] vals)

   Constructs a new object with the specified object ID and data.

   Parameters are:

   oid             The unique identifier of the operation.

   vals            The operation-specific data of the operation/


5.8.2.  getID

   public String getID()

   Returns the unique identifier of the operation.



5.8.3.  getValue

   public byte[] getValue()

   Returns the operation-specific data (not a copy, a reference).





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5.9.  public interface LDAPEntryComparator

An object of this class can implement arbitrary sorting algorithms for
search results.


5.9.1.  isGreater

   public boolean isGreater(LDAPEntry entry1, LDAPEntry entry2)

   Returns true if entry1 is to be considered greater than or equal to
   entry2, for the purpose of sorting.

   Parameters are:

   entry1          Target entry for comparison.

   entry2          Entry to be compared to.


5.10.  public class LDAPException extends Exception

Thrown to indicate that an error has occurred. An LDAPException can
result from physical problems (such as network errors) as well as prob-
lems with LDAP operations (for example, if the LDAP add operation fails
because of a duplicate entry).

Most errors that occur throw this type of exception.  The
getLDAPResultCode() method returns the specific result code, which can
be compared against standard LDAP result codes as defined in [11], sec-
tion 4.


5.10.1.  Constructors

   public LDAPException()

   Constructs a default exception with no specific error information.


   public LDAPException(String message,
                        int resultCode)

   Constructs an exception with an error code and a specified string as
   additional information.

   Parameters are:




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   message         The additional error information.

   resultCode      The result code returned


5.10.2.  getLDAPErrorMessage

   public String getLDAPErrorMessage()

   Returns the error message, if this message is available (that is, if
   this message was set). If the message was not set, this method
   returns null.


5.10.3.  getLDAPResultCode

   public int getLDAPResultCode()

   Returns the result code from the exception. The codes are defined as
   public final static int members of this class. If the exception is a
   result of error information returned from a directory operation, the
   code will be one of those defined in [11]. Otherwise, a local error
   code is returned (see "Error codes" below).

5.10.4.  getMatchedDN

   public String getMatchedDN()

   Returns the part of a submitted distinguished name which could be
   matched by the server. If the exception was caused by a local error,
   such as no server available, the return value is null. If the excep-
   tion resulted from an operation being executed on a server, the value
   is an empty String except when the result of the operation was one of
   the following:

      NO_SUCH_OBJECT
      ALIAS_PROBLEM
      INVALID_DN_SYNTAX
      ALIAS_DEREFERENCING_PROBLEM


5.10.5.  Error codes

See [11] and [7] for a discussion of the meanings of the codes.

     ADMIN_LIMIT_EXCEEDED
     AFFECTS_MULTIPLE_DSAS
     ALIAS_DEREFERENCING_PROBLEM



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     ALIAS_PROBLEM
     ATTRIBUTE_OR_VALUE_EXISTS
     AUTH_METHOD_NOT_SUPPORTED
     BUSY
     COMPARE_FALSE
     COMPARE_TRUE
     CONFIDENTIALITY_REQUIRED
     CONSTRAINT_VIOLATION
     ENTRY_ALREADY_EXISTS
     INAPPROPRIATE_AUTHENTICATION
     INAPPROPRIATE_MATCHING
     INSUFFICIENT_ACCESS_RIGHTS
     INVALID_ATTRIBUTE_SYNTAX
     INVALID_CREDENTIALS
     INVALID_DN_SYNTAX
     IS_LEAF
     LDAP_PARTIAL_RESULTS
     LOOP_DETECT
     NAMING_VIOLATION
     NO_SUCH_ATTRIBUTE
     NO_SUCH_OBJECT
     NOT_ALLOWED_ON_NONLEAF
     NOT_ALLOWED_ON_RDN
     OBJECT_CLASS_MODS_PROHIBITED
     OBJECT_CLASS_VIOLATION
     OPERATIONS_ERROR
     OTHER
     PROTOCOL_ERROR
     REFERRAL
     SIZE_LIMIT_EXCEEDED
     STRONG_AUTH_NOT_SUPPORTED
     STRONG_AUTH_REQUIRED
     SUCCESS
     TIME_LIMIT_EXCEEDED
     UNAVAILABLE
     UNAVAILABLE_CRITICAL_EXTENSION
     UNDEFINED_ATTRIBUTE_TYPE
     UNWILLING_TO_PERFORM

   Local errors, resulting from actions other than an operation on a
   server, are among the following:

     CONNECT_ERROR
     PARAM_ERROR
     SERVER_DOWN






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5.11.  public class LDAPModification

A single change specification for an LDAPAttribute.


5.11.1.  Constructors

   public LDAPModification(int op,
                           LDAPAttribute attr)

   Specifies a modification to be made to an attribute.

   Parameters are:

   op              The type of modification to make, which can be one of
                   the following:

      LDAPModification.ADD     The value should be added to the attri-
                               bute

      LDAPModification.DELETE  The value should be removed from the
                               attribute

      LDAPModification.REPLACE The value should replace all existing
                               values of the attribute

   attr            The attribute (possibly with values) to be modified.


5.11.2.  getAttribute

   public LDAPAttribute getAttribute()

   Returns the attribute (possibly with values) to be modified.


5.11.3.  getOp

   public int getOp()

   Returns the type of modification specified by this object.


5.12.  public class LDAPModificationSet

A collection of modifications to be made to the attributes of a single
entry.




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5.12.1.  Constructors

   public LDAPModificationSet()

   Constructs a new, empty set of modifications.


5.12.2.  add

   public synchronized void add(int op,
                                LDAPAttribute attr)

   Specifies another modification to be added to the set of modifica-
   tions.

   Parameters are:

   op              The type of modification to make, as described for
                   LDAPModification.

   attr            The attribute (possibly with values) to be modified.


5.12.3.  elementAt

   public LDAPModification elementAt(int index)
                               throws ArrayIndexOutOfBoundsException

   Retrieves a particular LDAPModification object at the position speci-
   fied by the index.

   Parameters are:

   index           Index of the modification to get.


5.12.4.  remove

   public synchronized void remove(String name)

   Removes the first attribute with the specified name in the set of
   modifications.

   Parameters are:

   name            Name of the attribute to be removed.





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5.12.5.  removeElementAt

   public void removeElementAt(int index)
                               throws ArrayIndexOutOfBoundsException

   Removes a particular LDAPModification object at the position speci-
   fied by the index.


index           Index of the modification to remove.


5.12.6.  size

   public int size()

   Retrieves the number of LDAPModification objects in this set.


5.13.  public class LDAPRebindAuth

Represents information used to authenticate the client in cases where
the client follows referrals automatically.


5.13.1.  Constructors

   public LDAPRebindAuth(String dn,
                         String password)

   Constructs information that is used by the client for authentication
   when following referrals automatically.


5.13.2.  getDN

   public String getDN()

   Returns the distinguished name to be used for reauthentication on
   automatic referral following.


5.13.3.  getPassword

   public String getPassword()

   Returns the password to be used for reauthentication on automatic
   referral following.



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5.14.  public class LDAPReferralException extends LDAPException

This exception, derived from LDAPException, is thrown when a server
returns a referral and automatic referral following has not been
enabled.


5.14.1.  Constructors

   public LDAPReferralException()

   Constructs a default exception with no specific error information.


   public LDAPReferralException(String message)

   Constructs a default exception with a specified string as additional
   information. This form is used for lower-level errors.


   public LDAPReferralException(String message,
                                int resultCode,
                                String serverMessage)

   Parameters are:

   message         The additional error information.

   resultCode      The result code returned

   serverMessage   Error message specifying additional information from
                   the server.


5.14.2.  getURLs

   public LDAPUrl[] getURLs()

   Gets the list of referrals (LDAP URLs to other servers) returned by
   the LDAP server. This exception is only thrown, and therefor the URL
   list only available, if automatic referral following is not enabled.
   The referrals may include URLs of a type other than ones for an LDAP
   server (i.e. a referral URL other than ldap://something).


5.15.  public class LDAPSearchConstraints

A set of options to control a search operation. There is always an



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LDAPSearchConstraints associated with an LDAPConnection object; its
values can be changed with LDAPConnection.setOption, or overridden by
passing an LDAPSearchConstraints object to the search operation.


5.15.1.  Constructors

   public LDAPSearchConstraints()

   Constructs an LDAPSearchConstraints object that specifies the default
   set of search constraints.


   public LDAPSearchConstraints(int msLimit,
                                int dereference,
                                int maxResults,
                                boolean doReferrals,
                                int batchSize,
                                LDAPRebind rebind_proc,
                                int hop_limit)

   Constructs a new LDAPSearchConstraints object and allows specifying
   the search constraints in that object.

   Parameters are:

   msLimit         Maximum time in milliseconds to wait for results (0
                   by default, which means that there is no maximum time
                   limit).

   dereference     Specifies when aliases should be dereferenced. Must
                   be either LDAP_DEREF_NEVER, LDAP_DEREF_FINDING,
                   LDAP_DEREF_SEARCHING, or LDAP_DEREF_ALWAYS from
                   LDAPv2 (LDAPv2.LDAP_DEREF_NEVER by default).

   maxResults      Maximum number of search results to return (1000 by
                   default).

   doReferrals     Specify true to follow referrals automatically, or
                   false to throw an LDAPReferralException error if the
                   server sends back a referral (false by default)

   batchSize       Specify the number of results to block on during
                   enumeration. 0 means to block until all results are
                   in (1 by default).

   rebind_proc     Specifies an object of the class that implements the
                   LDAPRebind interface. The object will be used when



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                   the client follows referrals automatically. The
                   object provides a method for getting the dis-
                   tinguished name and password used to authenticate to
                   another LDAP server during a referral. This field is
                   null by default.

   hop_limit       Maximum number of referrals to follow in a sequence
                   when attempting to resolve a request, when doing
                   automatic referral following.


5.15.2.  getBatchSize

   public int getBatchSize()

   Returns the number of results to block on during enumeration of
   search results. This should be 0 if intermediate results are not
   needed, and 1 if results are to be processed as they come in.


5.15.3.  getDereference

   public int getDereference()

   Specifies when aliases should be dereferenced. Returns either
   LDAP_DEREF_NEVER, LDAP_DEREF_FINDING, LDAP_DEREF_SEARCHING, or
   LDAP_DEREF_ALWAYS from LDAPv2.


5.15.4.  getHopLimit

   public int getHopLimit()

   Returns the maximum number of hops to follow during automatic refer-
   ral following.


5.15.5.  getMaxResults

   public int getMaxResults()

   Returns the maximum number of search results to be returned; 0 means
   no limit.


5.15.6.  getRebindProc

   public LDAPRebind getRebindProc()



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   Returns the object that provides the method for getting authentica-
   tion information.


5.15.7.  getReferrals

   public boolean getReferrals()

   Specifies whether nor not referrals are followed automatically.
   Returns true if referrals are to be followed automatically, or false
   if referrals throw an LDAPReferralException.


5.15.8.  getTimeLimit

   public int getTimeLimit()

   Returns the maximum number of milliseconds to wait for any operation
   under these search constraints. If 0, there is no maximum time limit
   on waiting for the operation results. The actual granularity of the
   timeout depends on the implementation.


5.15.9.  setBatchSize

   public void setBatchSize(int batchSize)

   Sets the suggested number of results to block on during enumeration
   of search results. This should be 0 if intermediate results are not
   needed, and 1 if results are to be processed as they come in.  The
   default is 1.

   Parameters are:

   batchSize       Blocking size on search enumerations.


5.15.10.  setDereference

   public void setDereference(int dereference)

   Sets a preference indicating whether or not aliases should be
   dereferenced, and if so, when.

   Parameters are:

   dereference     Either LDAP_DEREF_NEVER, LDAP_DEREF_FINDING,
                   LDAP_DEREF_SEARCHING, or LDAP_DEREF_ALWAYS from



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                   LDAPv2.


5.15.11.  setHopLimit

   public void setHopLimit(int hop_limit)

   Sets the maximum number of hops to follow in sequence during
   automatic referral following. The default is 5.

   Parameters are:

   hop_limit       Maximum number of chained referrals to follow
                   automatically.


5.15.12.  setMaxResults

   public void setMaxResults(int maxResults)

   Sets the maximum number of search results to be returned; 0 means no
   limit.  The default is 1000.

   Parameters are:

   maxResults      Maxumum number of search results to return.


5.15.13.  setRebindProc

   public void setRebindProc(LDAPRebind rebind_proc)

   Specifies the object that provides the method for getting authentica-
   tion information. The default is null. If referrals is set to true,
   and the rebindProc is null, referrals will be followed with anonymous
   (= no) authentication.

   Parameters are:

   rebind_proc     An object that implements LDAPRebind.


5.15.14.  setReferrals

   public void setReferrals(boolean doReferrals)

   Specifies whether nor not referrals are followed automatically, or if
   referrals throw an LDAPReferralException.  Referrals of any type



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   other to an LDAP server (i.e. a referral URL other than
   ldap://something) are ignored on automatic referral following. The
   default is false.

   Parameters are:

   doReferrals     True to follow referrals automatically.


5.15.15.  setTimeLimit

   public void setTimeLimit(int msLimit)

   Sets the maximum number of milliseconds to wait for any operation
   under these search constraints. If 0, there is no maximum time limit
   on waiting for the operation results. The actual granularity of the
   timeout depends on the implementation.

   Parameters are:

   msLimit         Maximum milliseconds to wait.


5.16.  public class LDAPSearchResults

An LDAPSearchResults object is returned from a search operation. It
implements Enumeration, thereby providing access to all entries
retrieved during the operation.


5.16.1.  hasMoreElements

   public boolean hasMoreElements()

   Specifies whether or not there are more search results in the
   enumeration. If true, there are more search results.


5.16.2.  next

   public LDAPEntry next() throws LDAPException

   Returns the next result in the enumeration as an LDAPEntry. If
   automatic referral following is disabled, and there are one or more
   referrals among the search results, next() will throw an LDAPRefer-
   ralException the last time it is called, after all other results have
   been returned.




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5.16.3.  nextElement

   public Object nextElement()

   Returns the next result in the enumeration as an Object. This the
   default implementation of Enumeration.nextElement(). The returned
   value may be an LDAPEntry or an LDAPReferralException.


5.16.4.  sort

   public void sort(LDAPEntryComparator comp)

   Sorts all entries in the results using the provided comparison
   object. If the object has been partially or completely enumerated,
   only remaining elements are sorted. Sorting the results requires that
   they all be present. This implies that
   LDAPSearchResults.nextElement() will always block until all results
   have been retrieved, after a sort operation.

   The LDAPCompareAttrNames class is provided to support the common need
   to collate by a single or multiple attribute values, in ascending or
   descending order.  Examples are:

       res.sort(new LDAPCompareAttrNames("cn"));

       res.sort(new LDAPCompareAttrNames("cn", false));

       String[] attrNames = { "sn", "givenname" };
       res.sort(new LDAPCompareAttrNames(attrNames));

   Parameters are:

   comp            An object that implements the LDAPEntryComparator
                   interface to compare two objects of type LDAPEntry.


5.17.  public interface LDAPSocketFactory

Used to construct a socket connection for use in an LDAPConnection.  An
implementation of this interface may, for example, provide a TLSSocket
connected to a secure server.


5.17.1.  makeSocket

   public Socket makeSocket(String host, int port)
                            throws IOException, UnknownHostException



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   Returns a socket connected using the provided host name and port
   number.

   There may be additional makeSocket methods defined when interfaces to
   establish TLS and SASL authentication in the java environment have
   been standardized.

   Parameters are:

   host            Contains a hostname or dotted string representing the
                   IP address of a host running an LDAP server to con-
                   nect to.

   port            Contains the TCP or UDP port number to connect to or
                   contact. The default LDAP port is 389.


5.18.  public class LDAPSortKey

Encapsulates parameters for sorting search results.

5.18.1.  Constructors


   public LDAPSortKey( String keyDescription )

   Constructs a new LDAPSortKey object using a, possibly complex, sort-
   ing specification.


   public LDAPSortKey( String key, boolean reverse)

   Constructs a new LDAPSortKey object using an attribute name and a
   sort order.


   public LDAPSortKey( String key, boolean reverse, String matchRule)

   Constructs a new LDAPSortKey object using an attribute name, a sort
   order, and a matching rule.

   Parameters are:

   keyDescription  A single attribute specification to sort by. If pre-
                   fixed with "-", reverse order sorting is requested. A
                   matching rule OID may be appended following ":".
                   Examples:
                      "cn"



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                      "-cn"
                      "-cn:1.2.3.4.5"

   key             An attribute name, e.g. "cn".

   reverse         True to sort in reverse collation order.

   matchRule       The object ID (OID) of a matching rule used for col-
                   lation. If the object will be used to request
                   server-side sorting of search results, it should be
                   the OID of a matching rule known to be supported by
                   that server.


5.18.2.  getKey


   public String getKey()

   Returns the attribute to be used for collation.


5.18.3.  getReverse

   public boolean getReverse()

   Returns true if the sort key specifies reverse-order sorting.


5.18.4.  getMatchRule

   public String getMatchRule()

   Returns the OID to be used as matching rule, or null if none is to be
   used.


5.19.  public class LDAPUrl

Encapsulates parameters of an LDAP Url query, as defined in [8].  An
LDAPUrl object can be passed to LDAPConnection.search to retrieve search
results.


5.19.1.  Constructors

   public LDAPUrl(String url) throws MalformedURLException




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   Constructs a URL object with the specified string as URL.


   public LDAPUrl(String host,
                  int port,
                  String dn)

   Constructs with the specified host, port, and DN. This form is used
   to create URL references to a particular object in the directory.


   public LDAPUrl(String host,
                  int port,
                  String dn,
                  String attrNames[],
                  int scope,
                  String filter)

   Constructs a full-blown LDAP URL to specify an LDAP search operation.

   Parameters are:

   url             An explicit URL string, e.g.
                   "ldap://ldap.acme.com:80/o=Ace%20Industry,c=us?cn,sn?sub?
                   (objectclass=inetOrgPerson)".

   host            Host name of LDAP server, or null for "nearest
                   X.500/LDAP".

   port            Port number for LDAP server (use
                   LDAPConnection.DEFAULT_PORT for default port).

   dn              Distinguished name of object to fetch.

   attrNames       Names of attributes to retrieve. null for all attri-
                   butes.

   scope           Depth of search (in DN namespace). Use one of
                   SCOPE_BASE, SCOPE_ONE, SCOPE_SUB from LDAPv2.


5.19.2.  decode

   public static String decode(String URLEncoded) throws MalformedURLEx-
   ception

   Decodes a URL-encoded string. Any occurences of %HH are decoded to
   the hex value represented. However, this routine does NOT decode "+"



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   into " ". See [10] for details on URL encoding/decoding.

   Parameters are:

   URLEncoded      String to decode.


5.19.3.  encode

   public static String encode(String toEncode)

   Encodes an arbitrary string. Any illegal characters are encoded as
   %HH.  However, this routine does NOT encode " " into "+".

   Parameters are:

   toEncode        String to encode.


5.19.4.  getAttributes

   public String[] getAttributeArray()

   Return an array of attribute names specified in the URL


5.19.5.  getAttributes

   public Enumeration getAttributes()

   Return an Enumerator for the attribute names specified in the URL


5.19.6.  getDN

   public String getDN()

   Return the distinguished name encapsulated in the URL.


5.19.7.  getFilter

   public String getFilter()

   Returns the search filter [8], or the default filter -
   (objectclass=*) - if none was specified.





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5.19.8.  getHost

   public String getHost()

   Returns the host name of the LDAP server to connect to.

5.19.9.  getPort

   public int getPort()

   Returns the port number of the LDAP server to connect to.


5.19.10.  getUrl

   public String getUrl()

   Returns a valid string representation of this LDAP URL.


5.20.  public interface LDAPv2

As a mechanism to support planned and future LDAP protocol extensions,
functionality is defined in an interface - LDAPv2, corresponding to ver-
sion 2 of the LDAP protocol. LDAPConnection must implement at least
LDAPv2, and may implement LDAPv3.  Applications can test for support of
these protocol levels in a given package with the instanceof operator.

5.20.1.  add

   public void add(LDAPEntry entry) throws LDAPException

   Adds an entry to the directory.

   Parameters are:

   entry           LDAPEntry object specifying the distinguished name
                   and attributes of the new entry.


5.20.2.  authenticate

   public void authenticate(String dn,
                            String passwd)
                            throws LDAPException

   Authenticates to the LDAP server (that the object is currently con-
   nected to) using the specified name and password.  If the object has



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   been disconnected from an LDAP server, this method attempts to recon-
   nect to the server. If the object had already authenticated, the old
   authentication is discarded.

   Parameters are:

   dn              If non-null and non-empty, specifies that the connec-
                   tion and all operations through it should be authen-
                   ticated with dn as the distinguished name.

   passwd          If non-null and non-empty, specifies that the connec-
                   tion and all operations through it should be authen-
                   ticated with dn as the distinguished name and passwd
                   as password.


5.20.3.  compare

   public boolean compare(String dn,
                          LDAPAttribute attr)
                          throws LDAPException

   Checks to see if an entry contains an attribute with a specified
   value.  Returns true if the entry has the value, and false if the
   entry does not have the value or the attribute.

   Parameters are:

   dn              The distinguished name of the entry to use in the
                   comparison.

   attr            The attribute to compare against the entry. The
                   method checks to see if the entry has an attribute
                   with the same name and value as this attribute.


5.20.4.  connect

   public void connect(String host,
                       int port)
                       throws LDAPException

   Connects to the specified host and port. If this LDAPConnection
   object represents an open connection, the connection is closed first
   before the new connection is opened.  At this point there is no
   authentication, and any operations will be conducted as an anonymous
   client.




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   public void connect(String host,
                       int port,
                       String dn,
                       String passwd)
                       throws LDAPException

   Connects to the specified host and port and uses the specified DN and
   password to authenticate to the server. If this LDAPConnection object
   represents an open connection, the connection is closed first before
   the new connection is opened. This is equivalent to connect(host,
   port) followed by authenticate(dn, passwd).

   Parameters are:

   host            Contains a hostname or dotted string representing the
                   IP address of a host running an LDAP server to con-
                   nect to. Alternatively, it may contain a list of host
                   names, space-delimited.  Each host name may include a
                   trailing colon and port number.  In the case where
                   more than one host name is specified, each host name
                   in turn will be contacted until a connection can be
                   established. Examples:

      "directory.knowledge.com"
      "199.254.1.2"
      "directory.knowledge.com:1050 people.catalog.com 199.254.1.2"

   port            Contains the TCP or UDP port number to connect to or
                   contact. The default LDAP port is 389. "port" is
                   ignored for any host name which includes a colon and
                   port number.

   dn              If non-null and non-empty, specifies that the connec-
                   tion and all operations through it should be authen-
                   ticated with dn as the distinguished name.

   passwd          If non-null and non-empty, specifies that the connec-
                   tion and all operations through it should be authen-
                   ticated with dn as the distinguished name and passwd
                   as password.


5.20.5.  delete

   public void delete(String dn) throws LDAPException

   Deletes the entry for the specified DN from the directory.




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   Parameters are:

   dn              Distinguished name of the entry to modify.


5.20.6.  disconnect

   public synchronized void disconnect() throws LDAPException

   Disconnects from the LDAP server. Before the object can perform LDAP
   operations again, it must reconnect to the server by calling connect.


5.20.7.  getOption

   public Object getOption(int option) throws LDAPException

   Returns the value of the specified option for this object.

   Parameters are:


   option          See LDAPConnection.setOption for a description of
                   valid options.


5.20.8.  modify

   public void modify(String dn,
                      LDAPModification mod)
                      throws LDAPException

   Makes a single change to an existing entry in the directory (for
   example, changes the value of an attribute, adds a new attribute
   value, or removes an existing attribute value).

   The LDAPModification object specifies both the change to be made and
   the LDAPAttribute value to be changed.


   public void modify(String dn,
                      LDAPModificationSet mods)
                      throws LDAPException

   Makes a set of changes to an existing entry in the directory (for
   example, changes attribute values, adds new attribute values, or
   removes existing attribute values).




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   Parameters are:

   dn              Distinguished name of the entry to modify.

   mod             A single change to be made to the entry.

   mods            A set of changes to be made to the entry.


5.20.9.  read

   public LDAPEntry read(String dn) throws LDAPException

   Reads the entry for the specified distiguished name (DN) and
   retrieves all attributes for the entry.


   public LDAPEntry read(String dn,
                         String attrs[])
                         throws LDAPException

   Reads the entry for the specified distinguished name (DN) and
   retrieves only the specified attributes from the entry.

   Parameters are:

   dn              Distinguished name of the entry to retrieve.

   attrs           Names of attributes to retrieve.


5.20.10.  rename

   public void rename(String dn,
                      String newRdn,
                      boolean deleteOldRdn)
                      throws LDAPException

   Renames an existing entry in the directory.

   Parameters are:

   dn              Current distinguished name of the entry.

   newRdn          New relative distinguished name for the entry.

   deleteOldRdn    If true, the old name is not retained as an attribute
                   value.



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5.20.11.  search

   public LDAPSearchResults search(String base,
                                   int scope,
                                   String filter,
                                   String attrs[],
                                   boolean attrsOnly)
                                   throws LDAPException

   Performs the search specified by the parameters.


   public LDAPSearchResults search(String base,
                                   int scope,
                                   String filter,
                                   String attrs[],
                                   boolean attrsOnly,
                                   LDAPSearchConstraints cons)
                                   throws LDAPException

   Performs the search specified by the parameters, also allowing
   specification of constraints for the search (such as the maximum
   number of entries to find or the maximum time to wait for search
   results).

   As part of the search constraints, the function allows specifying
   whether or not the results are to be delivered all at once or in
   smaller batches. If specified that the results are to be delivered in
   smaller batches, each iteration blocks only until the next batch of
   results is returned.

   Parameters are:

   base            The base distinguished name to search from.

   scope           The scope of the entries to search. The following are
                   the valid options:


                   LDAPv2.SCOPE_BASE Search only the base DN

                   LDAPv2.SCOPE_ONE  Search only entries under the base
                                     DN

                   LDAPv2.SCOPE_SUB  Search the base DN and all entries
                                     within its subtree

   filter          Search filter specifying the search criteria, as



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                   defined in [3].

   attrs           Names of attributes to retrieve.

   attrsOnly       If true, returns the names but not the values of the
                   attributes found.  If false, returns the names and
                   values for attributes found

   cons            Constraints specific to the search.


5.20.12.  setOption

   public void setOption(int option,
                         Object value)
                         throws LDAPException

   Sets the value of the specified option for this LDAPConnection
   object.

   See LDAPConnection.setOption for an implementation.


5.21.  public interface LDAPv3 extends LDAPv2

LDAPv3 extends LDAPv2 by adding support for features of version 3 of the
LDAP protocol. LDAPConnection implements at least LDAPv2, and may also
implement LDAPv3. Applications can test for support of these protocol
levels in a given package with the instanceof operator.

5.21.1.  Preferred Language

A preferred language, specified as in [14], can be set using setOption.
A Preferred Language Server Control is constructed and sent to the
server with all operations. If the server supports the control, results
returned on search() or read() will be filtered using the control, as
per [15], e.g.

      ld.setOption( LDAPv3.PREFERRED_LANGUAGE, "lang-en" );


5.21.2.  authenticate

   public void authenticate(int version,
                            String dn,
                            String passwd)
                            throws LDAPException




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   Authenticates to the LDAP server (that the object is currently con-
   nected to) using the specified name and password, with the specified
   LDAP protocol version. If the server does not support the requested
   protocol version, an exception is thrown.  If the object has been
   disconnected from an LDAP server, this method attempts to reconnect
   to the server. If the object had already authenticated, the old
   authentication is discarded.

   Parameters are:

   version         LDAP protocol version requested: currently 2 or 3.

   dn              If non-null and non-empty, specifies that the connec-
                   tion and all operations through it should be authen-
                   ticated with dn as the distinguished name.

   passwd          If non-null and non-empty, specifies that the connec-
                   tion and all operations through it should be authen-
                   ticated with dn as the distinguished name and passwd
                   as password.


5.21.3.  authenticate

   public void authenticate(String dn,
                            byte[] credentials,
                            String[] mechanisms,
                            Properties props,
                            SaslAuthenticationCallback authCb)
                            throws LDAPException

   Authenticates to the LDAP server using SASL authentication mechan-
   isms. Mechanisms will be tried in the order provided.  If a mechanism
   requires additional information (e.g.  credentials) to procede, and
   authCb is not null, authCb's request() method will be called. An
   LDAPException is thrown if authentication fails for all specified
   mechanisms.

   Parameters are:

   dn              Distinguished name to authenticate as

   credentials     Initial credentials to use on first authentication
                   request. The contents are specific to a SASL mechan-
                   ism.

   props           Properties to be used for authentication. Some are
                   only meaningful to a subset of all SASL mechanisms.



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                   The following is a partial list of properties and
                   sample values:

      security.userid                         "default"

      security.policy.encryption              "true"

      security.policy.sign_without_encryption "false"

      security.policy.no_encryption           "false"

      security.policy.encryption.minimum      "40"

      security.policy.encryption.maximum      "128"

      security.policy.server_authentication   "true"

      security.server.fqdn                    "safe.mcom.com"

      security.maxbuffer                      "4096"

      security.ip.local                       "192.68.1.10"

      security.ip.remote                      "192.68.1.50"


authCb          An object implementing the SaslAuthenticationCallback
                interface, capable of returning additional information
                to a SASL mechanism driver if necessary. This may or may
                not involve interactively prompting the user for this
                information. The parameter may be null, indicating that
                the application will not provide additional information.


5.21.4.  extendedOperation

   public LDAPExtendedOperation extendedOperation(
                                   LDAPExtendedOperation op )
                                   throws LDAPException

   Provides a means to access extended, non-mandatory operations offered
   by a particular LDAP version 3 compliant server.

   Returns an operation-specific object, containing an ID and an Octet
   String or BER-encoded value(s).

   Parameters are:




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   op              Object which contains an identifier of the extended
                   operation, which should be one recognized by the par-
                   ticular server this client is connected to, and an
                   operation-specific sequence of Octet String or BER-
                   encoded value(s).


5.21.5.  getResponseControls

   public LDAPControl[] getResponseControls()

   Returns the latest Server Controls returned by a Directory Server
   with a response to an LDAP request from the current thread, or null
   if the latest response contained no Server Controls.


5.21.6.  rename

   public void rename(String dn,
                      String newRdn,
                      String newParentdn,
                      boolean deleteOldRdn)
                      throws LDAPException

   Renames an existing entry in the directory, possibly repositioning it
   in the directory tree.

   Parameters are:

   dn              Current distinguished name of the entry.

   newRdn          New relative distinguished name for the entry.

   newParentdn     Distinguished name of the existing entry which is to
                   be the new parent of the entry.

   deleteOldRdn    If true, the old name is not retained as an attribute
                   value.


5.22.  public interface SaslAuthenticationCallback

Note: this interface is not part of the LDAP classes. It is presented
here to clarify use of SASL mechanisms in authentication using the LDAP
classes.

An application may implement this interface to allow a SASL mechanism
driver to obtain additional information (e.g. credentials) as needed



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during authentication. The implementation may or may not include
interactively prompting a user.

5.22.1.  request

   public byte[] request(String prompt,
                         String type)
                         throws SaslException

   Parameters are:

   prompt          A prompt that may be presented to a user as a guide
                   to entering the requested information, or may be used
                   as a key to forming the user interface for requesting
                   the information, or may be ignored.

   type            An identifier of type of information requested by the
                   SASL mechanism driver, e.g. "password".


5.23.  Client and Server Controls

LDAPv3 operations can be extended through the use of controls. Controls
may be sent to a server or returned to the client with any LDAP message.
These controls are referred to as server controls. The LDAP API also
supports a client-side extension mechanism through the use of client
controls (these controls affect the behavior of the LDAP API only and
are never sent to a server). A common class is used to represent both
types of controls - LDAPControl.

Controls are set and retrieved in LDAPConnection with the setOption and
getOption methods, using the keys LDAPv3.SERVERCONTROLS and
LDAPv3.CLIENTCONTROLS.  Either a single LDAPControl or an array may be
passed, e.g.

      LDAPControl control = new LDAPControl( type, critical, vals );
      ld.setOption( LDAPv3.SERVERCONTROLS, control );
   or
      LDAPControl[] controls = new LDAPControl[2];
      controls[0] = new LDAPControl( type0, critical0, vals0 );
      controls[1] = new LDAPControl( type1, critical1, vals1 );
      ld.setOption( LDAPv3.SERVERCONTROLS, controls );

Server controls returned to a client as part of the response to an
operation can be obtained with LDAPv3.getResponseControls().

Support for specific controls is defined in a package "controls" subor-
dinate to the main LDAP package.



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6.  Security Considerations

LDAP supports security through protocol-level authentication, using
clear-text passwords or other more secure mechanisms.  It also supports
running over TLS, which provides strong security at the transport layer.
This draft does not cover TLS implementations, although it identifies a
mechanism for supplying one, through the LDAPSocketFactory interface. An
interface is defined for using protocol-independent SASL mechanism
drivers for authentication.

7.  Acknowledgements

The proposed API builds on earlier work done in collaboration with Tho-
mas Kwan and Stephan Gudmundson, then of of NCware Technologies Corp.

8.  Bibliography

[1]  The Directory: Selected Attribute Syntaxes.  CCITT, Recommendation
     X.520.

[2]  M. Wahl, A. Coulbeck, T. Howes, S. Kille, "Lightweight Directory
     Access Protocol: Standard and Pilot Attribute Definitions", Inter-
     net Draft draft-ietf-asid-ldapv3-attributes-03.txt, October 1996

[3]  T. Howes, "A String Representation of LDAP Search Filters," RFC
     1960, June 1996.

[4]  S. Kille, "A String Representation of Distinguished Names," RFC
     1779, March 1995.

[5]  S. Kille, "Using the OSI Directory to Achieve User Friendly Nam-
     ing," RFC 1781, March 1995.

[7]  M. Wahl, T. Howes, S. Kille, "Lightweight Directory Access Protocol
     (v3)", Internet Draft draft-ietf-asid-ldapv3-protocol-04.txt, March
     1997.

[8]  T. Howes, M. Smith, "An LDAP URL Format", RFC 1959, June 1996.

[9]  T. Howes, M. Smith, "The LDAP Application Program Interface", RFC
     1823, August 1995.

[10] T. Berners-Lee, L. Masinter, M. McCahill, "Uniform Resource Loca-
     tors (URL)", RFC 1738, December 1994.

[11] W. Yeong, T. Howes, S. Kille, "Lightweight Directory Access Proto-
     col", RFC 1777, March 1995.




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[12] R. Weltman, "The Java LDAP Application Program Interface", Internet
     Draft draft-weltman-java-ldap-01.txt, April 1997.

[13] R. Weltman, T. Howes, M. Smith, "The Java LDAP Application Program
     Interface", Internet Draft draft-ietf-asid-ldap-java-api-00.txt,
     July 1997.

[14] H. Alvestrans, "Tags for the Identification of Languages", Request
     for Comments 1766, March 1995.

[15] M. Wahl, T. Howes, "Use of Language Codes in LDAPv3", Internet
     Draft draft-ietf-asid-ldapv3-lang-02.txt, June 1997.

9.  Authors' Addresses

   Rob Weltman
   Netscape Communications Corp.
   501 E. Middlefield Rd.
   Mountain View, CA 94043
   USA
   +1 650 937-3301
   rweltman@netscape.com

   Tim Howes
   Netscape Communications Corp.
   501 E. Middlefield Rd.
   Mountain View, CA 94043
   USA
   +1 650 937-3419
   howes@netscape.com

   Mark Smith
   Netscape Communications Corp.
   501 E. Middlefield Rd.
   Mountain View, CA 94043
   USA
   +1 650 937-3477
   mcs@netscape.com













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10.  Appendix A - Sample java LDAP programs

   import netscape.ldap.*;
   import java.util.*;

   public class SearchJensen {
       public static void main( String[] args )
       {
           try {
               LDAPConnection ld = new LDAPConnection();
               /* Connect to server */
               String MY_HOST = "localhost";
               int MY_PORT = 389;
               ld.connect( MY_HOST, MY_PORT );

               /* authenticate to the directory as nobody */
               /* This is not really necessary if explicit authentication
                  is not desired, because there is already anonymous
                  authentication at connect time */
               ld.authenticate( "", "" );

               /* search for all entries with surname of Jensen */
               String MY_FILTER = "sn=Jensen";
               String MY_SEARCHBASE = "o=Ace Industry, c=US";

               LDAPSearchConstraints cons = ld.getSearchConstraints();
               /* Setting the batchSize to one will cause the result
                  enumeration below to block on one result at a time,
                  allowing us to update a list or do other things as
                  results come in. */
               /* We could set it to 0 if we just wanted to get all
                  results and were willing to block until then */
               cons.setBatchSize( 1 );
               LDAPSearchResults res = ld.search( MY_SEARCHBASE,
                                                   LDAPConnection.SCOPE_ONE,
                                                   MY_FILTER,
                                                   null,
                                                   false,
                                                   cons );

               /* Loop on results until finished */
               while ( res.hasMoreElements() ) {

                   /* Next directory entry */
                   LDAPEntry findEntry = (LDAPEntry)res.nextElement();
                   System.out.println( findEntry.getDN() );

                   /* Get the attributes of the entry */



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                   LDAPAttributeSet findAttrs = findEntry.getAttributeSet();
                   Enumeration enumAttrs = findAttrs.getAttributes();
                   System.out.println( "Attributes: " );
                   /* Loop on attributes */
                   while ( enumAttrs.hasMoreElements() ) {
                       LDAPAttribute anAttr =
                           (LDAPAttribute)enumAttrs.nextElement();
                       String attrName = anAttr.getName();
                       System.out.println( "" + attrName );
                       /* Loop on values for this attribute */
                       Enumeration enumVals = anAttr.getStringValues();
                       while ( enumVals.hasMoreElements() ) {
                           String aVal = ( String )enumVals.nextElement();
                           System.out.println( "" + aVal );
                       }
                   }
               }
           }
           catch( LDAPException e ) {
               System.out.println( "Error: " + e.toString() );
           }
           /* Done, so disconnect */
           if ( ld.isConnected() )
               ld.disconnect();
       }
   }

























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   import netscape.ldap.*;
   import java.util.*;

   public class ModifyEmail {
       public static void main( String[] args )
       {
           try {
               LDAPConnection ld = new LDAPConnection();
               /* Connect to server */
               String MY_HOST = "localhost";
               int MY_PORT = 389;
               ld.connect( MY_HOST, MY_PORT );

               /* authenticate to the directory as Bab Jensen */
               String MY_NAME = "cn=Barbara Jensen,o=Ace Industry,c=US";
               String MY_PASSWORD = "MysteryLady";
               ld.authenticate( MY_NAME, MY_PASSWORD );

               /* Prepare to change my email address */
               LDAPAttribute attrEmail =
                       new LDAPAttribute( "mail", "babs@ace.com" );
               LDAPModification mod =
                       new LDAPModification( LDAPModification.REPLACE,
                                             attrEmail );

               /* Now modify the entry in the directory */
               ld.modify( MY_NAME, mod );
               System.out.println( "Entry modified"  );

           }
           catch( LDAPException e ) {
               System.out.println( "Error: " + e.toString() );
           }
           /* Done, so disconnect */
           if ( ld.isConnected() )
               ld.disconnect();
       }
   }













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11.  Appendix B - Changes from draft-ietf-asid-ldap-java-api-00.txt


11.1.  LDAPConnection

The method setProperty() throws an LDAPException if the specified pro-
perty is not supported.

11.2.  Controls

A section was added with support for currently defined LDAP controls.

11.3.  LDAPException

Constructors LDAPException(String) and LDAPException(String,int,String)
were removed, and the constructor LDAPException(String,int) was added.
The description stating that the resultCode is no longer valid was
removed.

11.4.  LDAPSearchResults

The method next() throws an LDAPReferralException if automatic referral
following is not enabled.

The getBaseAttribute() method was removed.

The getAttribute(attrName) method was redefined to return only an exact
match, and a new method getAttribute(attrName, lang) was added to pro-
vide language-sensitive best-match functionality. Neither method throws
an exception.

11.5.  LDAPSecurityException

The class was removed.

11.6.  LDAPSortKey

The class was added, to support server-side sorting.

11.7.  LDAPv3

The PREFERRED_LANGUAGE option was added to setOption().

11.8.  Examples

The disconnect() was moved to after the exception catcher.  An example
of using paged sort controls was added.




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12.  Appendix C - Changes from draft-weltman-java-ldap-00.txt


12.1.  LDAPv3

This interface is new. It adds support for features of LDAP protocol
version 3.

12.2.  SSL -> TLS

References to the Secure Socket Layer (SSL) have been replaced with
references to Transport Layer Security (TLS).

12.3.  LDAPAttributeSet

Methods getAttribute(String name) and getBaseAttribute(String name) were
added.

12.4.  LDAPCompareAttrNames

Constructors were added to allow specifying sorting in descending, and
not just ascending, order.

12.5.  LDAPCompareAttrNames

Constructors were added to allow specifying sorting in descending, and
not just ascending, order.

12.6.  LDAPControl

This is a new class to support the LDAPv3 protocol extension, where
Server or Client Controls may be specified for LDAP operations.

12.7.  LDAPEntry

Methods getAttribute(String name) and getBaseAttribute(String name) were
added.

12.8.  LDAPException

The method getMatchedDN was added.

12.9.  LDAPExtendedOperation

New class to pass extended operations back and forth to/from the server,
for LDAPv3.





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12.10.  LDAPv2

For connect(), the "host" parameter may be a space-delimited list of
hosts to attempt to connect to. Each one may have a colon and a port
number attached.

12.11.  Dereferencing aliases

LDAPConnection.setOption(), the LDAPSearchConstraints constructor,
LDAPSearchConstraints.getDereference(), and
LDAPSearchConstraints.setDereference() were changed so that the option
specifying how to dereference aliases is now an integer instead of a
boolean, and the legal values are declared.

12.12.  Default referral hop limit

The default referral hop limit in LDAPConnection.setOption() was changed
from 5 to 10.

12.13.  Examples

An example of how to modify an existing Directory entry was added to
appendix A.




























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JAVA LDAP API                                             September 1997


13.  Appendix D - Outstanding issues


13.1.  Support for SASL authentication

The framework suggested in the LDAPv3 interface for SASL authentication
is tentative. It will need to be extended to and integrated into the
automatic referral-processing architecture, so that an LDAPRebindProc
can initiate new authentication procedures with servers that are
referred to by a search. The current specification only allows for sim-
ple authentication on automatic referral following.

If referrals are handled explicitly rather than automatically, by catch-
ing LDAPReferralException, the caller may use the LDAPv3 SASL framework.





































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1.     Introduction...................................................1
2.     Overview of the LDAP model.....................................2
3.     Overview of the LDAP classes...................................3
3.1.      Interfaces..................................................3
3.2.      Classes.....................................................4
3.3.      Exceptions..................................................5
4.     Overview of LDAP API use.......................................6
5.     The java LDAP classes..........................................6
5.1.     LDAPAttribute................................................6
5.1.1.       Constructors.............................................6
5.1.2.       addValue.................................................7
5.1.3.       getByteValues............................................8
5.1.4.       getStringValues..........................................8
5.1.5.       getName..................................................8
5.1.6.       removeValue..............................................8
5.1.7.       size.....................................................8
5.2.     LDAPAttributeSet.............................................9
5.2.1.       Constructors.............................................9
5.2.2.       add......................................................9
5.2.3.       elementAt................................................9
5.2.4.       getAttribute.............................................9
5.2.5.       getAttributes............................................10
5.2.6.       remove...................................................11
5.2.7.       removeElementAt..........................................11
5.2.8.       size.....................................................11
5.3.     LDAPCompareAttrNames.........................................11
5.3.1.       Constructors.............................................11
5.3.2.       isGreater................................................12
5.4.     LDAPConnection...............................................13
5.4.1.       Constructors.............................................13
5.4.2.       clone....................................................13
5.4.3.       getAuthenticationDN......................................14
5.4.4.       getAuthenticationPassword................................14
5.4.5.       getHost..................................................14
5.4.6.       getPort..................................................14
5.4.7.       getProperty..............................................14
5.4.8.       getSearchConstraints.....................................15
5.4.9.       getSocketFactory.........................................15
5.4.10.      isAuthenticated..........................................15
5.4.11.      isConnected..............................................16
5.4.12.      read.....................................................16
5.4.13.      search...................................................16
5.4.14.      setOption................................................17
5.4.15.      setProperty..............................................20
5.4.16.      setSocketFactory.........................................21
5.5.     LDAPControl..................................................21
5.5.1.       Constructors.............................................22
5.5.2.       getID....................................................22
5.5.3.       isCritical...............................................22
5.5.4.       getValue.................................................22
5.6.     LDAPDN.......................................................22
5.6.1.       explodeDN................................................23





5.6.2.       explodeRDN...............................................23
5.7.     LDAPEntry....................................................23
5.7.1.       Constructors.............................................23
5.7.2.       getAttribute.............................................24
5.7.3.       getAttributeSet..........................................25
5.7.4.       getDN....................................................26
5.8.     LDAPExtendedOperation........................................26
5.8.1.       Constructors.............................................26
5.8.2.       getID....................................................26
5.8.3.       getValue.................................................26
5.9.     LDAPEntryComparator..........................................27
5.9.1.       isGreater................................................27
5.10.    LDAPException................................................27
5.10.1.      Constructors.............................................27
5.10.2.      getLDAPErrorMessage......................................28
5.10.3.      getLDAPResultCode........................................28
5.10.4.      getMatchedDN.............................................28
5.10.5.      Error codes..............................................28
5.11.    LDAPModification.............................................30
5.11.1.      Constructors.............................................30
5.11.2.      getAttribute.............................................30
5.11.3.      getOp....................................................30
5.12.    LDAPModificationSet..........................................30
5.12.1.      Constructors.............................................31
5.12.2.      add......................................................31
5.12.3.      elementAt................................................31
5.12.4.      remove...................................................31
5.12.5.      removeElementAt..........................................32
5.12.6.      size.....................................................32
5.13.    LDAPRebindAuth...............................................32
5.13.1.      Constructors.............................................32
5.13.2.      getDN....................................................32
5.13.3.      getPassword..............................................32
5.14.    LDAPReferralException........................................33
5.14.1.      Constructors.............................................33
5.14.2.      getURLs..................................................33
5.15.    LDAPSearchConstraints........................................33
5.15.1.      Constructors.............................................34
5.15.2.      getBatchSize.............................................35
5.15.3.      getDereference...........................................35
5.15.4.      getHopLimit..............................................35
5.15.5.      getMaxResults............................................35
5.15.6.      getRebindProc............................................35
5.15.7.      getReferrals.............................................36
5.15.8.      getTimeLimit.............................................36
5.15.9.      setBatchSize.............................................36
5.15.10.     setDereference...........................................36
5.15.11.     setHopLimit..............................................37
5.15.12.     setMaxResults............................................37
5.15.13.     setRebindProc............................................37
5.15.14.     setReferrals.............................................37
5.15.15.     setTimeLimit.............................................38





5.16.    LDAPSearchResults............................................38
5.16.1.      hasMoreElements..........................................38
5.16.2.      next.....................................................38
5.16.3.      nextElement..............................................39
5.16.4.      sort.....................................................39
5.17.    LDAPSocketFactory............................................39
5.17.1.      makeSocket...............................................39
5.18.    LDAPSortKey..................................................40
5.18.1.      Constructors.............................................40
5.18.2.      getKey...................................................41
5.18.3.      getReverse...............................................41
5.18.4.      getMatchRule.............................................41
5.19.    LDAPUrl......................................................41
5.19.1.      Constructors.............................................41
5.19.2.      decode...................................................42
5.19.3.      encode...................................................43
5.19.4.      getAttributes............................................43
5.19.5.      getAttributes............................................43
5.19.6.      getDN....................................................43
5.19.7.      getFilter................................................43
5.19.8.      getHost..................................................44
5.19.9.      getPort..................................................44
5.19.10.     getUrl...................................................44
5.20.    LDAPv2.......................................................44
5.20.1.      add......................................................44
5.20.2.      authenticate.............................................44
5.20.3.      compare..................................................45
5.20.4.      connect..................................................45
5.20.5.      delete...................................................46
5.20.6.      disconnect...............................................47
5.20.7.      getOption................................................47
5.20.8.      modify...................................................47
5.20.9.      read.....................................................48
5.20.10.     rename...................................................48
5.20.11.     search...................................................49
5.20.12.     setOption................................................50
5.21.    LDAPv3.......................................................50
5.21.1.      Preferred Language.......................................50
5.21.2.      authenticate.............................................50
5.21.3.      authenticate.............................................51
5.21.4.      extendedOperation........................................52
5.21.5.      getResponseControls......................................53
5.21.6.      rename...................................................53
5.22.    SaslAuthenticationCallback...................................53
5.22.1.      request..................................................54
5.23.     Client and Server Controls..................................54
6.     Security Considerations........................................55
7.     Acknowledgements...............................................55
8.     Bibliography...................................................55
9.     Authors' Addresses.............................................56
10.    Appendix A - Sample java LDAP programs.........................57
11.    Appendix B - Changes from draft-ietf-asid-ldap-java-api-00.txt.60





11.1.     LDAPConnection..............................................60
11.2.     Controls....................................................60
11.3.     LDAPException...............................................60
11.4.     LDAPSearchResults...........................................60
11.5.     LDAPSecurityException.......................................60
11.6.     LDAPSortKey.................................................60
11.7.     LDAPv3......................................................60
11.8.     Examples....................................................60
12.    Appendix C - Changes from draft-weltman-java-ldap-00.txt.......61
12.1.     LDAPv3......................................................61
12.2.     SSL -> TLS..................................................61
12.3.     LDAPAttributeSet............................................61
12.4.     LDAPCompareAttrNames........................................61
12.5.     LDAPCompareAttrNames........................................61
12.6.     LDAPControl.................................................61
12.7.     LDAPEntry...................................................61
12.8.     LDAPException...............................................61
12.9.     LDAPExtendedOperation.......................................61
12.10.    LDAPv2......................................................62
12.11.    Dereferencing aliases.......................................62
12.12.    Default referral hop limit..................................62
12.13.    Examples....................................................62
13.    Appendix D - Outstanding issues................................63
13.1.     Support for SASL authentication.............................63