src/main/java/org/apache/bsf/util/event/generator/AdapterClassLoader.java

/*
 * 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.
 *
 * @author   Rony G. Flatscher (added BSF_Log[Factory] to allow BSF to run without org.apache.commons.logging present)
 */

package org.apache.bsf.util.event.generator;

import org.apache.bsf.BSF_Log;
import org.apache.bsf.BSF_LogFactory;

import java.util.Hashtable;


public class AdapterClassLoader extends ClassLoader
{
  private static Hashtable classCache = new Hashtable();
  private Class c;

  // private Log logger = LogFactory.getLog(this.getClass().getName());
  private BSF_Log logger = null;

  public AdapterClassLoader()
  {
    super();
        logger = BSF_LogFactory.getLog(this.getClass().getName());
  }
  public synchronized Class defineClass(String name, byte[] b)
  {
    if ((c = getLoadedClass(name)) == null)
    {
      c = defineClass(name.replace('/','.'), b, 0, b.length);   // rgf, 2006-02-03
      put(name, c);
    }
    else
    {
      logger.error("AdapterClassLoader: " + c +
                                 " previously loaded. Can not redefine class.");
    }

    return c;
  }
  final protected Class findClass(String name)
  {
    return get(name);
  }
  final protected Class get(String name)
  {
    return (Class)classCache.get(name);
  }
  public synchronized Class getLoadedClass(String name)
  {
    Class c = findLoadedClass(name);

    if (c == null)
    {
      try
      {
        c = findSystemClass(name);
      }
      catch (ClassNotFoundException e)
      {
      }
    }

    if (c == null)
    {
      c = findClass(name);
    }

    return c;
  }
  protected synchronized Class loadClass(String name, boolean resolve)
    throws ClassNotFoundException
  {
    Class c = getLoadedClass(name);

    if (c != null && resolve)
    {
      resolveClass(c);
    }

    return c;
  }
  // Not in JDK 1.1, only in JDK 1.2.
//  public AdapterClassLoader(ClassLoader loader)
//  {
//    super(loader);
//  }

  final protected void put(String name, Class c)
  {
    classCache.put(name, c);
  }
}