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.mavibot.btree.exception;
021
022
023/**
024 * An exception thrown when we can't find a key in the BTree.
025 * 
026 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
027 */
028public class KeyNotFoundException extends Exception
029{
030    /** The serial version UUID */
031    private static final long serialVersionUID = 1L;
032    
033    /** A static Exception used to avoid creating a new one every time */
034    public static final KeyNotFoundException INSTANCE = new KeyNotFoundException(
035        "Cannot find an entry associated with this key" );
036
037
038    /**
039     * Creates a new instance of KeyNotFoundException.
040     */
041    public KeyNotFoundException()
042    {
043    }
044
045
046    /**
047     * Creates a new instance of KeyNotFoundException.
048     *
049     * @param explanation The message associated with the exception
050     */
051    public KeyNotFoundException( String explanation )
052    {
053        super( explanation );
054    }
055
056
057    /**
058     * Creates a new instance of KeyNotFoundException.
059     */
060    public KeyNotFoundException( Throwable cause )
061    {
062        super( cause );
063    }
064
065
066    /**
067     * Creates a new instance of KeyNotFoundException.
068     *
069     * @param explanation The message associated with the exception
070     * @param cause The root cause for this exception
071     */
072    public KeyNotFoundException( String explanation, Throwable cause )
073    {
074        super( explanation, cause );
075    }
076}