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.api.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 @Override 058 public void abandon() 059 { 060 if ( abandoned ) 061 { 062 return; 063 } 064 065 abandoned = true; 066 if ( o == null ) 067 { 068 o = new RequestObservable(); 069 } 070 o.setChanged(); 071 o.notifyObservers(); 072 o.deleteObservers(); 073 } 074 075 076 @Override 077 public boolean isAbandoned() 078 { 079 return abandoned; 080 } 081 082 083 /** 084 * {@inheritDoc} 085 */ 086 @Override 087 public AbandonableRequest addAbandonListener( final AbandonListener listener ) 088 { 089 if ( o == null ) 090 { 091 o = new RequestObservable(); 092 } 093 094 o.addObserver( new Observer() 095 { 096 @Override 097 public void update( Observable o, Object arg ) 098 { 099 listener.requestAbandoned( AbstractAbandonableRequest.this ); 100 } 101 } ); 102 103 return this; 104 } 105 106 // False positive 107 static class RequestObservable extends Observable 108 { 109 @Override 110 public void setChanged() 111 { 112 super.setChanged(); 113 } 114 } 115}