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 */ 019package org.apache.directory.api.ldap.model.cursor; 020 021 022import java.util.Iterator; 023 024import org.apache.directory.api.i18n.I18n; 025 026 027/** 028 * Simple class that contains often used Cursor code. 029 * 030 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 031 * @param <E> The type of element on which this cursor will iterate 032 */ 033public abstract class AbstractCursor<E> implements Cursor<E> 034{ 035 /** The default associated monitor */ 036 private ClosureMonitor monitor = new DefaultClosureMonitor(); 037 038 039 /** 040 * {@inheritDoc} 041 */ 042 public void setClosureMonitor( ClosureMonitor monitor ) 043 { 044 if ( monitor == null ) 045 { 046 throw new IllegalArgumentException( I18n.err( I18n.ERR_02001_MONITOR ) ); 047 } 048 049 this.monitor = monitor; 050 } 051 052 053 /** 054 * Check that the cursor is not closed before executing an operation. 055 * 056 * @param operation The operation we try to execute 057 * @throws CursorClosedException If there is a problem during the check 058 */ 059 public final void checkNotClosed( String operation ) throws CursorClosedException 060 { 061 monitor.checkNotClosed(); 062 } 063 064 065 /** 066 * {@inheritDoc} 067 */ 068 public boolean isClosed() 069 { 070 return monitor.isClosed(); 071 } 072 073 074 /** 075 * {@inheritDoc} 076 */ 077 public void close( Exception cause ) 078 { 079 monitor.close( cause ); 080 } 081 082 083 /** 084 * {@inheritDoc} 085 */ 086 public void close() 087 { 088 monitor.close(); 089 } 090 091 092 /** 093 * {@inheritDoc} 094 */ 095 public Iterator<E> iterator() 096 { 097 return new CursorIterator<E>( this ); 098 } 099 100 101 /** 102 * {@inheritDoc} 103 */ 104 public boolean isAfterLast() 105 { 106 throw new UnsupportedOperationException( I18n.err( I18n.ERR_02014_UNSUPPORTED_OPERATION, getClass().getName() 107 .concat( "." ).concat( "isAfterLast()" ) ) ); 108 } 109 110 111 /** 112 * {@inheritDoc} 113 */ 114 public boolean isBeforeFirst() 115 { 116 throw new UnsupportedOperationException( I18n.err( I18n.ERR_02014_UNSUPPORTED_OPERATION, getClass().getName() 117 .concat( "." ).concat( "isBeforeFirst()" ) ) ); 118 } 119 120 121 /** 122 * {@inheritDoc} 123 */ 124 public boolean isFirst() 125 { 126 throw new UnsupportedOperationException( I18n.err( I18n.ERR_02014_UNSUPPORTED_OPERATION, getClass().getName() 127 .concat( "." ).concat( "isFirst()" ) ) ); 128 } 129 130 131 /** 132 * {@inheritDoc} 133 */ 134 public boolean isLast() 135 { 136 throw new UnsupportedOperationException( I18n.err( I18n.ERR_02014_UNSUPPORTED_OPERATION, getClass().getName() 137 .concat( "." ).concat( "isLast()" ) ) ); 138 } 139 140 141 /** 142 * {@inheritDoc} 143 */ 144 public String toString( String tabs ) 145 { 146 return tabs; 147 } 148}