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    1   /***
    2    *
    3    * Copyright 2004 James Strachan
    4    *
    5    * Licensed under the Apache License, Version 2.0 (the "License");
    6    * you may not use this file except in compliance with the License.
    7    * You may obtain a copy of the License at
    8    *
    9    * http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   *
    17   **/
    18  package org.codehaus.groovy.control;
    19
    20  import org.codehaus.groovy.antlr.AntlrParserPluginFactory;
    21
    22  /***
    23   * A factory of parser plugin instances
    24   *
    25   * @version $Revision: 1.8 $
    26   */
    27  public abstract class ParserPluginFactory {
    28      public static ParserPluginFactory newInstance(boolean useNewParser) {
    29          if (useNewParser) {
    30              Class type = null;
    31              String name = "org.codehaus.groovy.antlr.AntlrParserPluginFactory";
    32              try {
    33                  type = Class.forName(name);
    34              }
    35              catch (ClassNotFoundException e) {
    36                  try {
    37                      type = ParserPluginFactory.class.getClassLoader().loadClass(name);
    38                  }
    39                  catch (ClassNotFoundException e1) {
    40                      ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();
    41                      if (contextClassLoader != null) {
    42                          try {
    43                              type = contextClassLoader.loadClass(name);
    44                          }
    45                          catch (ClassNotFoundException e2) {
    46                              // ignore
    47                          }
    48                      }
    49                  }
    50              }
    51
    52              if (type != null) {
    53                  try {
    54                      return (ParserPluginFactory) type.newInstance();
    55                  }
    56                  catch (Exception e) {
    57                      throw new RuntimeException("Could not create AntlrParserPluginFactory: " + e, e);
    58                  }
    59              }
    60              // can't find Antlr parser, so lets use the Classic one
    61          }
    62          return new AntlrParserPluginFactory();
    63      }
    64
    65      public abstract ParserPlugin createParserPlugin();
    66  }