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 */
020 package org.apache.directory.shared.ldap.filter;
021
022
023 /**
024 * Abstract base class for leaf nodes within the expression filter tree.
025 *
026 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
027 * @version $Rev: 746607 $
028 */
029 public class LeafNode extends AbstractExprNode
030 {
031 /** attribute on which this leaf is based */
032 private String attribute;
033
034
035 /**
036 * Creates a leaf node.
037 *
038 * @param attribute the attribute this node is based on
039 * @param assertionType the type of this leaf node
040 */
041 protected LeafNode( String attribute, AssertionType assertionType )
042 {
043 super( assertionType );
044 this.attribute = attribute;
045 }
046
047 /**
048 * Makes a full clone in new memory space of the current node and children
049 *
050 * @return the clone
051 */
052 @Override public ExprNode clone()
053 {
054 return super.clone();
055 }
056
057
058 /**
059 * Gets whether this node is a leaf - the answer is always true here.
060 *
061 * @return true always
062 */
063 public final boolean isLeaf()
064 {
065 return true;
066 }
067
068
069 /**
070 * Gets the attribute this leaf node is based on.
071 *
072 * @return the attribute asserted
073 */
074 public final String getAttribute()
075 {
076 return attribute;
077 }
078
079
080 /**
081 * Sets the attribute this leaf node is based on.
082 *
083 * @param attribute the attribute that is asserted by this filter node
084 */
085 public void setAttribute( String attribute )
086 {
087 this.attribute = attribute;
088 }
089
090
091 /**
092 * @see org.apache.directory.shared.ldap.filter.ExprNode#accept(
093 * org.apache.directory.shared.ldap.filter.FilterVisitor)
094 *
095 * @param visitor the filter expression tree structure visitor
096 * @return The modified element
097 */
098 public final Object accept( FilterVisitor visitor )
099 {
100 if ( visitor.canVisit( this ) )
101 {
102 return visitor.visit( this );
103 }
104 else
105 {
106 return null;
107 }
108 }
109
110
111 /**
112 * @see Object#hashCode()
113 * @return the instance's hash code
114 */
115 public int hashCode()
116 {
117 int h = 37;
118
119 h = h*17 + super.hashCode();
120 h = h*17 + attribute.hashCode();
121
122 return h;
123 }
124
125
126 /*
127 * (non-Javadoc)
128 *
129 * @see java.lang.Object#equals(java.lang.Object)
130 */
131 public boolean equals( Object other )
132 {
133 if ( this == other )
134 {
135 return true;
136 }
137
138 if ( !( other instanceof LeafNode ) )
139 {
140 return false;
141 }
142
143 //noinspection SimplifiableIfStatement
144 if ( other.getClass() != this.getClass() )
145 {
146 return false;
147 }
148
149 return attribute.equals( ( ( LeafNode ) other ).getAttribute() );
150 }
151 }