| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * |
| */ |
| |
| package org.apache.directory.ldap.client.api.future; |
| |
| |
| import java.util.concurrent.BlockingQueue; |
| import java.util.concurrent.ExecutionException; |
| import java.util.concurrent.Future; |
| import java.util.concurrent.LinkedBlockingQueue; |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.TimeoutException; |
| |
| import org.apache.directory.api.ldap.model.message.Response; |
| import org.apache.directory.ldap.client.api.LdapConnection; |
| |
| |
| /** |
| * A Future implementation used in LdapConnection operations. |
| * |
| * @param <R> The result type returned by this Future's <tt>get</tt> method |
| * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> |
| */ |
| public class ResponseFuture<R extends Response> implements Future<Response> |
| { |
| /** the blocking queue holding LDAP responses */ |
| protected BlockingQueue<R> queue; |
| |
| /** flag to determine if this future is cancelled */ |
| protected boolean cancelled = false; |
| |
| /** If the request has been cancelled because of an exception it will be stored here */ |
| protected Throwable cause; |
| |
| /** The messageID for this future */ |
| protected int messageId; |
| |
| /** The connection used by the request */ |
| protected LdapConnection connection; |
| |
| |
| /** |
| * Creates a new instance of ResponseFuture. |
| * |
| * @param connection The LdapConnection used by the request |
| * @param messageId The associated message ID |
| */ |
| public ResponseFuture( LdapConnection connection, int messageId ) |
| { |
| queue = new LinkedBlockingQueue<R>(); |
| this.messageId = messageId; |
| this.connection = connection; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean cancel( boolean mayInterruptIfRunning ) |
| { |
| if ( cancelled ) |
| { |
| return cancelled; |
| } |
| |
| // set the cancel flag first |
| cancelled = true; |
| |
| // Send an abandonRequest only if this future exists |
| if ( connection.doesFutureExistFor( messageId ) ) |
| { |
| connection.abandon( messageId ); |
| } |
| |
| // then clear the queue, cause the might be some incoming messages before this abandon request |
| // hits the server |
| queue.clear(); |
| |
| return cancelled; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| * @throws InterruptedException if the operation has been cancelled by client |
| */ |
| public R get() throws InterruptedException, ExecutionException |
| { |
| R response = null; |
| |
| response = queue.take(); |
| |
| return response; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| * @throws InterruptedException if the operation has been cancelled by client |
| */ |
| public void set( R response ) throws InterruptedException, ExecutionException |
| { |
| queue.add( response ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| * @throws InterruptedException if the operation has been cancelled by client |
| */ |
| public R get( long timeout, TimeUnit unit ) throws InterruptedException, ExecutionException, TimeoutException |
| { |
| R response = queue.poll( timeout, unit ); |
| |
| return response; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean isCancelled() |
| { |
| return cancelled; |
| } |
| |
| |
| /** |
| * This operation is not supported in this implementation of Future. |
| * |
| * {@inheritDoc} |
| */ |
| public boolean isDone() |
| { |
| throw new UnsupportedOperationException( "Operation not supported" ); |
| } |
| |
| |
| /** |
| * @return the cause |
| */ |
| public Throwable getCause() |
| { |
| return cause; |
| } |
| |
| |
| /** |
| * Associate a cause to the ResponseFuture |
| * @param cause the cause to set |
| */ |
| public void setCause( Throwable cause ) |
| { |
| this.cause = cause; |
| } |
| |
| |
| /** |
| * Cancel the Future |
| * |
| */ |
| public void cancel() |
| { |
| // set the cancel flag first |
| cancelled = true; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public String toString() |
| { |
| StringBuilder sb = new StringBuilder(); |
| |
| sb.append( "[msgId : " ).append( messageId ).append( ", " ); |
| sb.append( "size : " ).append( queue.size() ).append( ", " ); |
| sb.append( "Canceled :" ).append( cancelled ).append( "]" ); |
| |
| return sb.toString(); |
| } |
| } |