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 }