1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * https://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.directory.api.ldap.model.filter;
21
22
23 import org.apache.directory.api.i18n.I18n;
24
25
26 /**
27 * Node used for the application of arbitrary predicates on return candidates.
28 * Applies dynamic and programatic criteria for the selection of candidates for
29 * return. Nodes of this type may be introduced into the filter expression to
30 * provided the opportunity to constrain the search further without altering the
31 * search algorithm.
32 *
33 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
34 */
35 public abstract class AssertionNode extends AbstractExprNode
36 {
37 /** The assertion or predicate to apply */
38 private final Assertion assertion;
39
40 /** Description of assertion for polish printouts */
41 private final String desc;
42
43
44 // ------------------------------------------------------------------------
45 // C O N S T R U C T O R S
46 // ------------------------------------------------------------------------
47
48 /**
49 * Creates an AssertionNode using an arbitrary candidate assertion.
50 *
51 * @param assertion the arbitrary selection logic.
52 */
53 public AssertionNode( Assertion assertion )
54 {
55 this( assertion, "ASSERTION" );
56 }
57
58
59 /**
60 * Creates an AssertionNode using an arbitrary candidate assertion with a
61 * descriptions used for filter AST walker dumps.
62 *
63 * @param assertion the arbitrary selection logic.
64 * @param desc the printout representation for filter prints.
65 */
66 public AssertionNode( Assertion assertion, String desc )
67 {
68 super( AssertionType.ASSERTION );
69 this.desc = desc;
70 this.assertion = assertion;
71
72 /*
73 * We never want this node to ever make it to the point of becoming a
74 * candidate for use in an enumeration so we set the scan count to the
75 * maximum value.
76 */
77 set( "count", Long.MAX_VALUE );
78 }
79
80
81 /**
82 * Gets the Assertion used by this assertion node.
83 *
84 * @return the assertion used by this node
85 */
86 public Assertion getAssertion()
87 {
88 return assertion;
89 }
90
91
92 // ------------------------------------------------------------------------
93 // 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
94 // ------------------------------------------------------------------------
95
96 /**
97 * Always returns true since an AssertionNode has no children.
98 *
99 * @see ExprNode#isLeaf()
100 * @return true if the node is a leaf,false otherwise
101 */
102 @Override
103 public boolean isLeaf()
104 {
105 return true;
106 }
107
108
109 /**
110 * @see ExprNode#printRefinementToBuffer(StringBuilder)
111 */
112 @Override
113 public StringBuilder printRefinementToBuffer( StringBuilder buf )
114 {
115 throw new UnsupportedOperationException( I18n.err( I18n.ERR_13304_ASSERTIONNODE_IN_REFINEMENT ) );
116 }
117
118
119 /**
120 * Tells if this Node is Schema aware.
121 *
122 * @return true if the Node is SchemaAware
123 */
124 @Override
125 public boolean isSchemaAware()
126 {
127 return true;
128 }
129
130
131 /**
132 * {@inheritDoc}
133 */
134 @Override
135 public boolean equals( Object obj )
136 {
137 if ( obj == this )
138 {
139 return true;
140 }
141
142 if ( !( obj instanceof AssertionNode ) )
143 {
144 return false;
145 }
146 AssertionNode that = ( AssertionNode ) obj;
147 if ( assertion == null )
148 {
149 if ( that.assertion != null )
150 {
151 return false;
152 }
153 }
154 else
155 {
156 if ( !assertion.equals( that.assertion ) )
157 {
158 return false;
159 }
160 }
161 if ( desc == null )
162 {
163 if ( that.desc != null )
164 {
165 return false;
166 }
167 }
168 else
169 {
170 if ( !desc.equals( that.desc ) )
171 {
172 return false;
173 }
174 }
175 return super.equals( obj );
176 }
177
178
179 /**
180 * @see Object#hashCode()
181 * @return the instance's hash code
182 */
183 @Override
184 public int hashCode()
185 {
186 int h = 37;
187
188 h = h * 17 + super.hashCode();
189 h = h * 17 + ( assertion != null ? assertion.hashCode() : 0 );
190 h = h * 17 + ( desc != null ? desc.hashCode() : 0 );
191
192 return h;
193 }
194
195
196 /**
197 * @see ExprNode#accept(
198 *FilterVisitor)
199 */
200 @Override
201 public Object accept( FilterVisitor visitor )
202 {
203 return visitor.visit( this );
204 }
205
206
207 /**
208 * @see Object#toString
209 * @return A string representing the AndNode
210 */
211 @Override
212 public String toString()
213 {
214 StringBuilder buf = new StringBuilder();
215
216 buf.append( "(@" );
217 buf.append( desc );
218 buf.append( super.toString() );
219 buf.append( ')' );
220
221 return buf.toString();
222 }
223 }