001 /** 002 * 003 * Copyright 2004 James Strachan 004 * 005 * Licensed under the Apache License, Version 2.0 (the "License"); 006 * you may not use this file except in compliance with the License. 007 * You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 * 017 **/ 018 package org.codehaus.groovy.control; 019 020 import org.codehaus.groovy.antlr.AntlrParserPluginFactory; 021 022 /** 023 * A factory of parser plugin instances 024 * 025 * @version $Revision: 1.8 $ 026 */ 027 public abstract class ParserPluginFactory { 028 public static ParserPluginFactory newInstance(boolean useNewParser) { 029 if (useNewParser) { 030 Class type = null; 031 String name = "org.codehaus.groovy.antlr.AntlrParserPluginFactory"; 032 try { 033 type = Class.forName(name); 034 } 035 catch (ClassNotFoundException e) { 036 try { 037 type = ParserPluginFactory.class.getClassLoader().loadClass(name); 038 } 039 catch (ClassNotFoundException e1) { 040 ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader(); 041 if (contextClassLoader != null) { 042 try { 043 type = contextClassLoader.loadClass(name); 044 } 045 catch (ClassNotFoundException e2) { 046 // ignore 047 } 048 } 049 } 050 } 051 052 if (type != null) { 053 try { 054 return (ParserPluginFactory) type.newInstance(); 055 } 056 catch (Exception e) { 057 throw new RuntimeException("Could not create AntlrParserPluginFactory: " + e, e); 058 } 059 } 060 // can't find Antlr parser, so lets use the Classic one 061 } 062 return new AntlrParserPluginFactory(); 063 } 064 065 public abstract ParserPlugin createParserPlugin(); 066 }