directoryclassloader.java

webwork source

package webwork.util.classloader;

import java.io.*;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;

import webwork.util.ClassLoaderUtils;

/**
 * User: Hani Suleiman
 * Date: Oct 22, 2003
 * Time: 3:57:08 PM
 */
public class DirectoryClassLoader extends WebworkClassLoader
{
  private File directory;
  private Map timestamps = new HashMap();

  public DirectoryClassLoader(File file, ClassLoader parent)
  {
    super(parent);
    this.directory = file;
  }

  public boolean isStale()
  {
    Iterator iter = timestamps.entrySet().iterator();
    while(iter.hasNext())
    {
      Map.Entry entry = (Map.Entry)iter.next();
      File toCheck = new File(directory, (String)entry.getKey());
      long time = ((Long)entry.getValue()).longValue();
      if(toCheck.lastModified() > time)
      {
        return true;
      }
    }
    return false;
  }

  protected URL getDataURL(String name, byte[] data) throws MalformedURLException
  {
    return new URL(null, directory.toURL().toExternalForm() + '/' + name, new BytesURLStreamHandler(data));
  }

  public byte[] getFile(String path)
  {
    try
    {
      InputStream in = null;
      int size = 0;

      File f = new File(directory, path);
      if(!f.exists()) return null;
        size = (int)f.length();
        in = new FileInputStream(f);
        //we're ok not storing timestamps for jars, since the whole jar
        //will be modified in that case.
        timestamps.put(path, new Long(f.lastModified()));

      byte[] data = ClassLoaderUtils.readStream(in, size);
      return data;
    }
    catch(IOException e)
    {
      return null;
    }
  }

  public Object clone()
  {
    DirectoryClassLoader loader = new DirectoryClassLoader(directory, getParent());
    loader.packages = packages;
    return loader;
  }
}