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 */ 020 021 package org.apache.directory.shared.ldap.filter; 022 023 024 /** 025 * Root expression node interface which all expression nodes in the filter 026 * expression tree implement. 027 * 028 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 029 * @version $Revision: 746607 $ 030 */ 031 public interface ExprNode extends Cloneable 032 { 033 /** 034 * Gets an annotation on the tree by key. 035 * 036 * @param key the annotation key. 037 * @return the annotation value. 038 */ 039 Object get( Object key ); 040 041 042 /** 043 * Sets a annotation key to a value. 044 * 045 * @param key the annotation key. 046 * @param value the annotation value. 047 */ 048 void set( String key, Object value ); 049 050 051 /** 052 * Tests to see if this node is a leaf or branch node. 053 * 054 * @return true if the node is a leaf,false otherwise 055 */ 056 boolean isLeaf(); 057 058 059 /** 060 * Gets the assertion type of this node. Make it possible to use switch 061 * statements on the node type. 062 * 063 * @return the assertion type 064 */ 065 AssertionType getAssertionType(); 066 067 /** 068 * Recursively appends the refinement string representation of this node and its 069 * descendants in prefix notation to a buffer. 070 * 071 * TODO - Why is this here? Why not put it in some utility class? 072 * 073 * @param buf the buffer to append to. 074 * @return The buffer in which the refinement has been appended 075 * @throws UnsupportedOperationException if this node isn't a part of a refinement. 076 * @return the refinement buffer 077 */ 078 StringBuilder printRefinementToBuffer( StringBuilder buf ); 079 080 081 /** 082 * Element/node accept method for visitor pattern. 083 * 084 * @param visitor the filter expression tree structure visitor 085 * TODO - what is this modified element ? 086 * @return the modified element 087 */ 088 Object accept( FilterVisitor visitor ); 089 090 091 /** 092 * Clone the object 093 * @return 094 */ 095 ExprNode clone(); 096 }