| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * |
| */ |
| |
| package org.apache.directory.shared.ldap.trigger; |
| |
| |
| import java.io.StringReader; |
| import java.text.ParseException; |
| |
| import org.apache.directory.shared.i18n.I18n; |
| import org.apache.directory.shared.ldap.schema.NormalizerMappingResolver; |
| |
| import antlr.RecognitionException; |
| import antlr.TokenStreamException; |
| |
| |
| /** |
| * A reusable wrapper around the ANTLR generated parser for a |
| * TriggerSpecification. This class enables the reuse of the antlr parser/lexer |
| * pair without having to recreate them every time. |
| * |
| * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> |
| */ |
| public class TriggerSpecificationParser |
| { |
| /** the antlr generated parser being wrapped */ |
| private ReusableAntlrTriggerSpecificationParser parser; |
| |
| /** the antlr generated lexer being wrapped */ |
| private ReusableAntlrTriggerSpecificationLexer lexer; |
| |
| private final boolean isNormalizing; |
| |
| |
| /** |
| * Creates a TriggerSpecification parser. |
| */ |
| public TriggerSpecificationParser() |
| { |
| this.lexer = new ReusableAntlrTriggerSpecificationLexer( new StringReader( "" ) ); |
| this.parser = new ReusableAntlrTriggerSpecificationParser( lexer ); |
| |
| this.parser.init(); // this method MUST be called while we cannot do |
| // constructor overloading for antlr generated parser |
| this.isNormalizing = false; |
| } |
| |
| |
| /** |
| * Creates a normalizing TriggerSpecification parser. |
| */ |
| public TriggerSpecificationParser( NormalizerMappingResolver resolver ) |
| { |
| this.lexer = new ReusableAntlrTriggerSpecificationLexer( new StringReader( "" ) ); |
| this.parser = new ReusableAntlrTriggerSpecificationParser( lexer ); |
| |
| this.parser.setNormalizerMappingResolver( resolver ); |
| this.parser.init(); // this method MUST be called while we cannot do |
| // constructor overloading for ANTLR generated parser |
| this.isNormalizing = true; |
| } |
| |
| |
| /** |
| * Initializes the plumbing by creating a pipe and coupling the parser/lexer |
| * pair with it. |
| * |
| * @param |
| * spec the specification to be parsed |
| */ |
| private synchronized void reset( String spec ) |
| { |
| StringReader in = new StringReader( spec ); |
| this.lexer.prepareNextInput( in ); |
| this.parser.resetState(); |
| } |
| |
| |
| /** |
| * Parses an TriggerSpecification without exhausting the parser. |
| * |
| * @param spec |
| * the specification to be parsed |
| * @return the specification bean |
| * @throws ParseException |
| * if there are any recognition errors (bad syntax) |
| */ |
| public synchronized TriggerSpecification parse( String spec ) throws ParseException |
| { |
| TriggerSpecification triggerSpecification = null; |
| |
| if ( spec == null || spec.trim().equals( "" ) ) |
| { |
| return null; |
| } |
| |
| reset( spec ); // reset and initialize the parser / lexer pair |
| |
| try |
| { |
| triggerSpecification = this.parser.wrapperEntryPoint(); |
| } |
| catch ( TokenStreamException e ) |
| { |
| String msg = I18n.err( I18n.ERR_04333, spec, e.getLocalizedMessage() ); |
| throw new ParseException( msg, 0 ); |
| } |
| catch ( RecognitionException e ) |
| { |
| String msg = I18n.err( I18n.ERR_04333, spec, e.getLocalizedMessage() ); |
| throw new ParseException( msg, e.getColumn() ); |
| } |
| |
| return triggerSpecification; |
| |
| } |
| |
| |
| /** |
| * Tests to see if this parser is normalizing. |
| * |
| * @return true if it normalizes false otherwise |
| */ |
| public boolean isNormizing() |
| { |
| return this.isNormalizing; |
| } |
| } |