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.shared.ldap.codec.controls.search.pagedSearch; 021 022 023import org.apache.directory.shared.asn1.DecoderException; 024import org.apache.directory.shared.asn1.ber.grammar.AbstractGrammar; 025import org.apache.directory.shared.asn1.ber.grammar.Grammar; 026import org.apache.directory.shared.asn1.ber.grammar.GrammarAction; 027import org.apache.directory.shared.asn1.ber.grammar.GrammarTransition; 028import org.apache.directory.shared.asn1.ber.tlv.UniversalTag; 029import org.apache.directory.shared.asn1.ber.tlv.Value; 030import org.apache.directory.shared.asn1.ber.tlv.IntegerDecoder; 031import org.apache.directory.shared.asn1.ber.tlv.IntegerDecoderException; 032import org.apache.directory.shared.i18n.I18n; 033import org.apache.directory.shared.util.StringConstants; 034import org.slf4j.Logger; 035import org.slf4j.LoggerFactory; 036 037 038/** 039 * This class implements the PagedSearchControl. All the actions are declared in 040 * this class. As it is a singleton, these declaration are only done once. 041 * 042 * The decoded grammar is the following : 043 * 044 * realSearchControlValue ::= SEQUENCE { 045 * size INTEGER, 046 * cookie OCTET STRING, 047 * } 048 * 049 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 050 */ 051public final class PagedResultsGrammar extends AbstractGrammar<PagedResultsContainer> 052{ 053 /** The logger */ 054 static final Logger LOG = LoggerFactory.getLogger( PagedResultsGrammar.class ); 055 056 /** Speedup for logs */ 057 static final boolean IS_DEBUG = LOG.isDebugEnabled(); 058 059 /** The instance of grammar. PagedSearchControlGrammar is a singleton */ 060 private static Grammar<?> instance = new PagedResultsGrammar(); 061 062 063 /** 064 * Creates a new PagedSearchControlGrammar object. 065 */ 066 @SuppressWarnings("unchecked") 067 private PagedResultsGrammar() 068 { 069 setName( PagedResultsGrammar.class.getName() ); 070 071 // Create the transitions table 072 super.transitions = new GrammarTransition[ PagedResultsStates.LAST_PAGED_SEARCH_STATE.ordinal()][256]; 073 074 /** 075 * Transition from initial state to PagedSearch sequence 076 * realSearchControlValue ::= SEQUENCE OF { 077 * ... 078 * 079 * Nothing to do 080 */ 081 super.transitions[ PagedResultsStates.START_STATE.ordinal()][UniversalTag.SEQUENCE.getValue()] = 082 new GrammarTransition<PagedResultsContainer>( PagedResultsStates.START_STATE, 083 PagedResultsStates.PAGED_SEARCH_SEQUENCE_STATE, 084 UniversalTag.SEQUENCE.getValue(), null ); 085 086 087 /** 088 * Transition from PagedSearch sequence to size 089 * 090 * realSearchControlValue ::= SEQUENCE OF { 091 * size INTEGER, -- INTEGER (0..maxInt), 092 * ... 093 * 094 * Stores the size value 095 */ 096 super.transitions[ PagedResultsStates.PAGED_SEARCH_SEQUENCE_STATE.ordinal()][UniversalTag.INTEGER.getValue()] = 097 new GrammarTransition<PagedResultsContainer>( PagedResultsStates.PAGED_SEARCH_SEQUENCE_STATE, 098 PagedResultsStates.SIZE_STATE, 099 UniversalTag.INTEGER.getValue(), 100 new GrammarAction<PagedResultsContainer>( "Set PagedSearchControl size" ) 101 { 102 public void action( PagedResultsContainer container ) throws DecoderException 103 { 104 Value value = container.getCurrentTLV().getValue(); 105 106 try 107 { 108 // Check that the value is into the allowed interval 109 int size = IntegerDecoder.parse( value, Integer.MIN_VALUE, Integer.MAX_VALUE ); 110 111 // We allow negative value to absorb a bug in some M$ client. 112 // Those negative values will be transformed to Integer.MAX_VALUE. 113 if ( size < 0 ) 114 { 115 size = Integer.MAX_VALUE; 116 } 117 118 if ( IS_DEBUG ) 119 { 120 LOG.debug( "size = " + size ); 121 } 122 123 container.getDecorator().setSize( size ); 124 } 125 catch ( IntegerDecoderException e ) 126 { 127 String msg = I18n.err( I18n.ERR_04050 ); 128 LOG.error( msg, e ); 129 throw new DecoderException( msg ); 130 } 131 } 132 } ); 133 134 /** 135 * Transition from size to cookie 136 * realSearchControlValue ::= SEQUENCE OF { 137 * ... 138 * cookie OCTET STRING 139 * } 140 * 141 * Stores the cookie flag 142 */ 143 super.transitions[ PagedResultsStates.SIZE_STATE.ordinal()][UniversalTag.OCTET_STRING.getValue()] = 144 new GrammarTransition<PagedResultsContainer>( PagedResultsStates.SIZE_STATE, 145 PagedResultsStates.COOKIE_STATE, UniversalTag.OCTET_STRING.getValue(), 146 new GrammarAction<PagedResultsContainer>( "Set PagedSearchControl cookie" ) 147 { 148 public void action( PagedResultsContainer container ) throws DecoderException 149 { 150 Value value = container.getCurrentTLV().getValue(); 151 152 if ( container.getCurrentTLV().getLength() == 0 ) 153 { 154 container.getDecorator().setCookie( StringConstants.EMPTY_BYTES ); 155 } 156 else 157 { 158 container.getDecorator().setCookie( value.getData() ); 159 } 160 161 // We can have an END transition 162 container.setGrammarEndAllowed( true ); 163 } 164 } ); 165 } 166 167 168 /** 169 * This class is a singleton. 170 * 171 * @return An instance on this grammar 172 */ 173 public static Grammar<?> getInstance() 174 { 175 return instance; 176 } 177}