Overview | Package | Class | Use | Tree | Deprecated | Index | Help
| JavaTM 2 Platform Std. Ed. v1.3.1
PREV PACKAGE NEXT PACKAGE | FRAMES NO FRAMES

## Package javax.naming.ldap

Provides support for LDAPv3 extended operations and controls.

See:
Description

Interface Summary
Control | This interface represents an LDAPv3 control as defined in RFC 2251.
ExtendedRequest | This interface represents an LDAPv3 extended operation request as defined in RFC 2251.
ExtendedResponse | This interface represents an LDAP extended operation response as defined in RFC 2251.
HasControls | This interface is for returning controls with objects returned in NamingEnumerations.
LdapContext | This interface represents a context in which you can perform operations with LDAPv3-style controls and perform LDAPv3-style extended operations.
UnsolicitedNotification | This interface represents an unsolicited notification as defined in RFC 2251.
UnsolicitedNotificationListener | This interface is for handling `UnsolicitedNotificationEvent`.

Class Summary
ControlFactory | This abstract class represents a factory for creating LDAPv3 controls.
InitialLdapContext | This class is the starting context for performing LDAPv3-style extended operations and controls.
UnsolicitedNotificationEvent | This class represents an event fired in response to an unsolicited notification sent by the LDAP server.

Exception Summary
LdapReferralException | This abstract class is used to represent an LDAP referral exception.

## Package javax.naming.ldap Description

Provides support for LDAPv3 extended operations and controls.

This package extends the directory operations of the Java Naming and Directory InterfaceTM (JNDI). JNDI provides naming and directory functionality to applications written in the Java programming language. It is designed to be independent of any specific naming or directory service implementation. Thus a variety of services--new, emerging, and already deployed ones--can be accessed in a common way.

This package is for applications and service providers that deal with LDAPv3 extended operations and controls, as defined by RFC 2251. The core interface in this package is `LdapContext`, which defines methods on a context for performing extended operations and handling controls.

#### Extended Operations

This package defines the interface `ExtendedRequest` to represent the argument to an extended operation, and the interface `ExtendedResponse` to represent the result of the extended operation. An extended response is always paired with an extended request but not necessarily vice versa. That is, you can have an extended request that has no corresponding extended response.

An application typically does not deal directly with these interfaces. Instead, it deals with classes that implement these interfaces. The application gets these classes either as part of a repertoire of extended operations standardized through the IETF, or from directory vendors for vendor-specific extended operations. The request classes should have constructors that accept arguments in a type-safe and user-friendly manner, while the response classes should have access methods for getting the data of the response in a type-safe and user-friendly manner. Internally, the request/response classes deal with encoding and decoding BER values.

For example, suppose an LDAP server supports a "get time" extended operation. It would supply classes such as `GetTimeRequest` and `GetTimeResponse`, so that applications can use this feature. An application would use these classes as follows:

>     GetTimeResponse resp =
>         (GetTimeResponse) ectx.extendedOperation(new GetTimeRequest());
>     long time = resp.getTime();

The `GetTimeRequest` and `GetTimeResponse` classes might be defined as follows:

>     public class GetTimeRequest implements ExtendedRequest {
>         // User-friendly constructor
>         public GetTimeRequest() {
>         };

>         // Methods used by service providers
>         public String getID() {
>             return GETTIME_REQ_OID;
>         }
>         public byte[] getEncodedValue() {
>             return null;  // no value needed for get time request
>         }
>         public ExtendedResponse createExtendedResponse(
>             String id, byte[] berValue, int offset, int length) throws NamingException {
>             return new GetTimeResponse(id, berValue, offset, length);
>         }
>     }
>     public class GetTimeResponse() implements ExtendedResponse {
>         long time;
>         // called by GetTimeRequest.createExtendedResponse()
>         public GetTimeResponse(String id, byte[] berValue, int offset, int length)
>             throws NamingException {
>             // check validity of id
>             long time =  ... // decode berValue to get time
>         }

>         // Type-safe and User-friendly methods
>         public java.util.Date getDate() { return new java.util.Date(time); }
>         public long getTime() { return time; }

>         // Low level methods
>         public byte[] getEncodedValue() {
>             return // berValue saved;
>         }
>         public String getID() {
>             return GETTIME_RESP_OID;
>         }
>     }

#### Controls

This package defines the interface `Control` to represent an LDAPv3 control. It can be a control that is sent to an LDAP server (request control) or a control returned by an LDAP server (response control). Unlike extended requests and responses, there is not necessarily any pairing between request controls and response controls. You can send request controls and expect no response controls back, or receive response controls without sending any request controls.

An application typically does not deal directly with this interface. Instead, it deals with classes that implement this interface. The application gets control classes either as part of a repertoire of controls standardized through the IETF, or from directory vendors for vendor-specific controls. The request control classes should have constructors that accept arguments in a type-safe and user-friendly manner, while the response control classes should have access methods for getting the data of the response in a type-safe and user-friendly manner. Internally, the request/response control classes deal with encoding and decoding BER values.

For example, suppose an LDAP server supports a "sort" request control, which when sent with a search request, asks the server to return the results of the search ordered by a particular attribute It would supply a class `SortControl` so that applications can use this feature. An application would use this class as follows:

>     Control[] reqCtls = new Control[] {new SortControl("age")};
>     ectx.setRequestControls(reqCtls);
>     NamingEnumeration enum = ectx.search(...);

The `SortControl` class might be defined as follows:

>     public class SortControl implements Control {
>         // User-friendly constructor
>         public SortControl(String attrID) {
>             // encode attrID
>         };

>         // Methods used by service providers
>         public String getID() {
>             return SORT_OID;
>         }
>         public byte[] getEncodedValue() {
>             return // encoded attrID
>         }
>         ...
>     }

When a service provider receives response controls, it uses the `ControlFactory` class to produce specific classes that implement the `Control` interface.

An LDAP server can send back response controls with an LDAP operation and also with enumeration results, such as those returned by a list or search operation. The `LdapContext` provides a method (`getResponseControls()`) for getting the response controls sent with an LDAP operation, while the `HasControls` interface is used to retrieve response controls associated with enumeration results.

For example, suppose an LDAP server sends back a "change ID" control in response to a successful modification. It would supply a class `ChangeIDControl` so that the application can use this feature. An application would perform an update, and then try to get the change ID.

>     // Perform update
>     Context ctx = ectx.createSubsubcontext("cn=newobj");

>     // Get response controls
>     Control[] respCtls = ectx.getResponseControls();
>     if (respCtls != null) {
>         // Find the one we want
>         for (int i = 0; i < respCtls; i++) {
>             if(respCtls[i] instanceof ChangeIDControl) {
>     	    ChangeIDControl cctl = (ChangeIDControl)respCtls[i];
>     	    System.out.println(cctl.getChangeID());
>             }
>         }
>     }

The vendor might supply the following `ChangeIDControl` and `VendorXControlFactory` classes. The `VendorXControlFactory` will be used by the service provider when the provider receives response controls from the LDAP server.

>     public class ChangeIDControl implements Control {
>         long id;

>         // Constructor used by ControlFactory
>         public ChangeIDControl(String OID, byte[] berVal) throws NamingException {
>             // check validity of OID
>             id = // extract change ID from berVal
>         };

>         // Type-safe and User-friendly method
>         public long getChangeID() {
>             return id;
>         }

>         // Low-level methods
>         public String getID() {
>             return CHANGEID_OID;
>         }
>         public byte[] getEncodedValue() {
>             return // original berVal
>         }
>         ...
>     }
>     public class VendorXControlFactory extends ControlFactory {
>         public VendorXControlFactory () {
>         }

>         public Control getControlInstance(Control orig) throws NamingException {
>             if (isOneOfMyControls(orig.getID())) {
>     	    ...

>     	    // determine which of ours it is and call its constructor
>     	    return (new ChangeIDControl(orig.getID(), orig.getEncodedValue()));
>     	}
>             return null;  // not one of ours
>         }
>     }

## Package Specification

The following documents can be found at the Java technology web site:

- JNDI API Document (Postscript)
- JNDI API Document (PDF)

Since:
  1.3

Overview | Package | Class | Use | Tree | Deprecated | Index | Help
| JavaTM 2 Platform Std. Ed. v1.3.1
PREV PACKAGE NEXT PACKAGE | FRAMES NO FRAMES

Submit a bug or feature
For further API reference and developer documentation, see Java 2 SDK SE Developer Documentation. That documentation contains more detailed, developer-targeted descriptions, with conceptual overviews, definitions of terms, workarounds, and working code examples.

Java, Java 2D, and JDBC are trademarks or registered trademarks of Sun Microsystems, Inc. in the US and other countries.
Copyright 1993-2001 Sun Microsystems, Inc. 901 San Antonio Road
Palo Alto, California, 94303, U.S.A. All Rights Reserved.