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.filter; 021 022 023import org.apache.directory.api.i18n.I18n; 024 025 026/** 027 * Node used for the application of arbitrary predicates on return candidates. 028 * Applies dynamic and programatic criteria for the selection of candidates for 029 * return. Nodes of this type may be introduced into the filter expression to 030 * provided the opportunity to constrain the search further without altering the 031 * search algorithm. 032 * 033 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 034 */ 035public abstract class AssertionNode extends AbstractExprNode 036{ 037 /** The assertion or predicate to apply */ 038 private final Assertion assertion; 039 040 /** Description of assertion for polish printouts */ 041 private final String desc; 042 043 044 // ------------------------------------------------------------------------ 045 // C O N S T R U C T O R S 046 // ------------------------------------------------------------------------ 047 048 /** 049 * Creates an AssertionNode using an arbitrary candidate assertion. 050 * 051 * @param assertion the arbitrary selection logic. 052 */ 053 public AssertionNode( Assertion assertion ) 054 { 055 this( assertion, "ASSERTION" ); 056 057 isSchemaAware = true; 058 } 059 060 061 /** 062 * Creates an AssertionNode using an arbitrary candidate assertion with a 063 * descriptions used for filter AST walker dumps. 064 * 065 * @param assertion the arbitrary selection logic. 066 * @param desc the printout representation for filter prints. 067 */ 068 public AssertionNode( Assertion assertion, String desc ) 069 { 070 super( AssertionType.ASSERTION ); 071 this.desc = desc; 072 this.assertion = assertion; 073 074 /* 075 * We never want this node to ever make it to the point of becoming a 076 * candidate for use in an enumeration so we set the scan count to the 077 * maximum value. 078 */ 079 set( "count", Long.MAX_VALUE ); 080 } 081 082 083 /** 084 * Gets the Assertion used by this assertion node. 085 * 086 * @return the assertion used by this node 087 */ 088 public Assertion getAssertion() 089 { 090 return assertion; 091 } 092 093 094 // ------------------------------------------------------------------------ 095 // A B S T R A C T M E T H O D I M P L E M E N T A T I O N S 096 // ------------------------------------------------------------------------ 097 098 /** 099 * Always returns true since an AssertionNode has no children. 100 * 101 * @see ExprNode#isLeaf() 102 * @return true if the node is a leaf,false otherwise 103 */ 104 @Override 105 public boolean isLeaf() 106 { 107 return true; 108 } 109 110 111 /** 112 * @see ExprNode#printRefinementToBuffer(StringBuilder) 113 */ 114 @Override 115 public StringBuilder printRefinementToBuffer( StringBuilder buf ) 116 { 117 throw new UnsupportedOperationException( I18n.err( I18n.ERR_04145 ) ); 118 } 119 120 121 /** 122 * {@inheritDoc} 123 */ 124 @Override 125 public boolean equals( Object obj ) 126 { 127 if ( obj == this ) 128 { 129 return true; 130 } 131 132 if ( ( obj == null ) || !( obj instanceof AssertionNode ) ) 133 { 134 return false; 135 } 136 AssertionNode that = ( AssertionNode ) obj; 137 if ( assertion == null ) 138 { 139 if ( that.assertion != null ) 140 { 141 return false; 142 } 143 } 144 else 145 { 146 if ( !assertion.equals( that.assertion ) ) 147 { 148 return false; 149 } 150 } 151 if ( desc == null ) 152 { 153 if ( that.desc != null ) 154 { 155 return false; 156 } 157 } 158 else 159 { 160 if ( !desc.equals( that.desc ) ) 161 { 162 return false; 163 } 164 } 165 return super.equals( obj ); 166 } 167 168 169 /** 170 * @see Object#hashCode() 171 * @return the instance's hash code 172 */ 173 @Override 174 public int hashCode() 175 { 176 int h = 37; 177 178 h = h * 17 + super.hashCode(); 179 h = h * 17 + ( assertion != null ? assertion.hashCode() : 0 ); 180 h = h * 17 + ( desc != null ? desc.hashCode() : 0 ); 181 182 return h; 183 } 184 185 186 /** 187 * @see ExprNode#accept( 188 *FilterVisitor) 189 */ 190 @Override 191 public Object accept( FilterVisitor visitor ) 192 { 193 return visitor.visit( this ); 194 } 195 196 197 /** 198 * @see Object#toString 199 * @return A string representing the AndNode 200 */ 201 @Override 202 public String toString() 203 { 204 StringBuilder buf = new StringBuilder(); 205 206 buf.append( "(@" ); 207 buf.append( desc ); 208 buf.append( super.toString() ); 209 buf.append( ')' ); 210 211 return buf.toString(); 212 } 213}