001/* 002 * Licensed to the Apache Software Foundation (ASF) under one 003 * or more contributor license agreements. See the NOTICE file 004 * distributed with this work for additional information 005 * regarding copyright ownership. The ASF licenses this file 006 * to you under the Apache License, Version 2.0 (the 007 * "License"); you may not use this file except in compliance 008 * with the License. You may obtain a copy of the License at 009 * 010 * http://www.apache.org/licenses/LICENSE-2.0 011 * 012 * Unless required by applicable law or agreed to in writing, 013 * software distributed under the License is distributed on an 014 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 015 * KIND, either express or implied. See the License for the 016 * specific language governing permissions and limitations 017 * under the License. 018 * 019 */ 020package org.apache.directory.shared.ldap.model.message; 021 022 023import java.util.Observable; 024import java.util.Observer; 025 026 027/** 028 * The base abandonable request message class. All such requests have a response 029 * type. 030 * 031 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 032 */ 033public class AbstractAbandonableRequest extends AbstractRequest implements AbandonableRequest 034{ 035 static final long serialVersionUID = -4511116249089399040L; 036 037 /** Flag indicating whether or not this request returns a response. */ 038 private boolean abandoned = false; 039 040 private RequestObservable o; 041 042 043 /** 044 * Subclasses must provide these parameters via a super constructor call. 045 * 046 * @param id 047 * the sequential message identifier 048 * @param type 049 * the request type enum 050 */ 051 protected AbstractAbandonableRequest( final int id, final MessageTypeEnum type ) 052 { 053 super( id, type, true ); 054 } 055 056 057 public void abandon() 058 { 059 if ( abandoned ) 060 { 061 return; 062 } 063 064 abandoned = true; 065 if ( o == null ) 066 { 067 o = new RequestObservable(); 068 } 069 o.setChanged(); 070 o.notifyObservers(); 071 o.deleteObservers(); 072 } 073 074 075 public boolean isAbandoned() 076 { 077 return abandoned; 078 } 079 080 081 /** 082 * {@inheritDoc} 083 */ 084 public AbandonableRequest addAbandonListener( final AbandonListener listener ) 085 { 086 if ( o == null ) 087 { 088 o = new RequestObservable(); 089 } 090 091 o.addObserver( new Observer() 092 { 093 public void update( Observable o, Object arg ) 094 { 095 listener.requestAbandoned( AbstractAbandonableRequest.this ); 096 } 097 } ); 098 099 return this; 100 } 101 102 103 // False positive 104 static class RequestObservable extends Observable 105 { 106 @Override 107 public void setChanged() 108 { 109 super.setChanged(); 110 } 111 } 112}