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 * http://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 21 package org.apache.directory.api.ldap.aci; 22 23 24 import java.io.StringReader; 25 import java.text.ParseException; 26 27 import org.apache.directory.api.i18n.I18n; 28 import org.apache.directory.api.ldap.model.schema.SchemaManager; 29 30 import antlr.RecognitionException; 31 import antlr.TokenStreamException; 32 33 34 /** 35 * A reusable wrapper around the antlr generated parser for an ACIItem as 36 * defined by X.501. This class enables the reuse of the antlr parser/lexer pair 37 * without having to recreate them every time. 38 * 39 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> 40 */ 41 public class ACIItemChecker 42 { 43 /** the antlr generated parser being wrapped */ 44 private ReusableAntlrACIItemParser checker; 45 46 /** the antlr generated lexer being wrapped */ 47 private ReusableAntlrACIItemLexer lexer; 48 49 50 /** 51 * Creates a ACIItem parser. 52 * 53 * @param schemaManager the schema manager 54 */ 55 public ACIItemChecker( SchemaManager schemaManager ) 56 { 57 this.lexer = new ReusableAntlrACIItemLexer( new StringReader( "" ) ); 58 this.checker = new ReusableAntlrACIItemParser( lexer ); 59 this.checker.init( schemaManager ); 60 } 61 62 63 /** 64 * Initializes the plumbing by creating a pipe and coupling the parser/lexer 65 * pair with it. param spec the specification to be parsed 66 */ 67 private synchronized void reset( String spec ) 68 { 69 StringReader in = new StringReader( spec ); 70 this.lexer.prepareNextInput( in ); 71 this.checker.resetState(); 72 } 73 74 75 /** 76 * Parses an ACIItem without exhausting the parser. 77 * 78 * @param spec 79 * the specification to be parsed 80 * @throws ParseException 81 * if there are any recognition errors (bad syntax) 82 */ 83 public synchronized void parse( String spec ) throws ParseException 84 { 85 if ( spec == null || spec.trim().equals( "" ) ) 86 { 87 return; 88 } 89 90 reset( spec ); // reset and initialize the parser / lexer pair 91 92 try 93 { 94 this.checker.wrapperEntryPoint(); 95 } 96 catch ( TokenStreamException e ) 97 { 98 throw new ParseException( I18n 99 .err( I18n.ERR_04004_PARSER_FAILURE_ACI_ITEM, spec, e.getLocalizedMessage() ), 0 ); 100 } 101 catch ( RecognitionException e ) 102 { 103 throw new ParseException( I18n 104 .err( I18n.ERR_04004_PARSER_FAILURE_ACI_ITEM, spec, e.getLocalizedMessage() ), e.getColumn() ); 105 } 106 } 107 108 }