// ========================================================================
// Copyright 1999-2005 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// Licensed 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.
// ========================================================================
package org.mortbay.jetty.webapp;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import java.net.URLClassLoader;
import java.security.CodeSource;
import java.security.PermissionCollection;
import java.util.StringTokenizer;
import org.mortbay.jetty.handler.ContextHandler;
import org.mortbay.log.Log;
import org.mortbay.resource.Resource;
import org.mortbay.util.IO;
import org.mortbay.util.LazyList;
/* ------------------------------------------------------------ */
/** ClassLoader for HttpContext.
* Specializes URLClassLoader with some utility and file mapping
* methods.
*
* This loader defaults to the 2.3 servlet spec behaviour where non
* system classes are loaded from the classpath in preference to the
* parent loader. Java2 compliant loading, where the parent loader
* always has priority, can be selected with the
* {@link org.mortbay.jetty.webapp.WebAppContext#setParentLoaderPriority(boolean)} method.
*
* If no parent class loader is provided, then the current thread context classloader will
* be used. If that is null then the classloader that loaded this class is used as the parent.
*
* @author Greg Wilkins (gregw)
*/
public class WebAppClassLoader extends URLClassLoader
{
private String _name;
private WebAppContext _context;
private ClassLoader _parent;
/* ------------------------------------------------------------ */
/** Constructor.
*/
public WebAppClassLoader(WebAppContext context)
throws IOException
{
this(null,context);
}
/* ------------------------------------------------------------ */
/** Constructor.
*/
public WebAppClassLoader(ClassLoader parent, WebAppContext context)
throws IOException
{
super(new URL[]{},parent!=null?parent
:(Thread.currentThread().getContextClassLoader()!=null?Thread.currentThread().getContextClassLoader()
:(WebAppClassLoader.class.getClassLoader()!=null?WebAppClassLoader.class.getClassLoader()
:ClassLoader.getSystemClassLoader())));
_parent=getParent();
_context=context;
if (_parent==null)
throw new IllegalArgumentException("no parent classloader!");
if (context.getExtraClasspath()!=null)
addClassPath(context.getExtraClasspath());
}
/* ------------------------------------------------------------ */
/**
* @return the name of the classloader
*/
public String getName()
{
return _name;
}
/* ------------------------------------------------------------ */
/**
* @param name the name of the classloader
*/
public void setName(String name)
{
_name=name;
}
/* ------------------------------------------------------------ */
public ContextHandler getContext()
{
return _context;
}
/* ------------------------------------------------------------ */
/**
* @param classPath Comma or semicolon separated path of filenames or URLs
* pointing to directories or jar files. Directories should end
* with '/'.
*/
public void addClassPath(String classPath)
throws IOException
{
if (classPath == null)
return;
StringTokenizer tokenizer= new StringTokenizer(classPath, ",;");
while (tokenizer.hasMoreTokens())
{
Resource resource= Resource.newResource(tokenizer.nextToken());
if (Log.isDebugEnabled())
Log.debug("Path resource=" + resource);
// Resolve file path if possible
File file= resource.getFile();
if (file != null)
{
URL url= resource.getURL();
addURL(url);
}
else
{
// Add resource or expand jar/
if (!resource.isDirectory() && file == null)
{
InputStream in= resource.getInputStream();
File tmp_dir=_context.getTempDirectory();
if (tmp_dir==null)
{
tmp_dir = File.createTempFile("jetty.cl.lib",null);
tmp_dir.mkdir();
tmp_dir.deleteOnExit();
}
File lib= new File(tmp_dir, "lib");
if (!lib.exists())
{
lib.mkdir();
lib.deleteOnExit();
}
File jar= File.createTempFile("Jetty-", ".jar", lib);
jar.deleteOnExit();
if (Log.isDebugEnabled())
Log.debug("Extract " + resource + " to " + jar);
FileOutputStream out = null;
try
{
out= new FileOutputStream(jar);
IO.copy(in, out);
}
finally
{
IO.close(out);
}
URL url= jar.toURL();
addURL(url);
}
else
{
URL url= resource.getURL();
addURL(url);
}
}
}
}
/* ------------------------------------------------------------ */
/** Add elements to the class path for the context from the jar and zip files found
* in the specified resource.
* @param lib the resource that contains the jar and/or zip files.
* @param append true if the classpath entries are to be appended to any
* existing classpath, or false if they replace the existing classpath.
* @see #setClassPath(String)
*/
public void addJars(Resource lib)
{
if (lib.exists() && lib.isDirectory())
{
String[] files=lib.list();
for (int f=0;files!=null && f<files.length;f++)
{
try {
Resource fn=lib.addPath(files[f]);
String fnlc=fn.getName().toLowerCase();
if (fnlc.endsWith(".jar") || fnlc.endsWith(".zip"))
{
addClassPath(fn.toString());
}
}
catch (Exception ex)
{
Log.warn(Log.EXCEPTION,ex);
}
}
}
}
/* ------------------------------------------------------------ */
public void destroy()
{
this._parent=null;
}
/* ------------------------------------------------------------ */
public PermissionCollection getPermissions(CodeSource cs)
{
// TODO check CodeSource
PermissionCollection permissions=_context.getPermissions();
PermissionCollection pc= (permissions == null) ? super.getPermissions(cs) : permissions;
return pc;
}
/* ------------------------------------------------------------ */
public synchronized URL getResource(String name)
{
URL url= null;
boolean tried_parent= false;
if (_context.isParentLoaderPriority() || isSystemPath(name))
{
tried_parent= true;
if (_parent!=null)
url= _parent.getResource(name);
}
if (url == null)
{
url= this.findResource(name);
if (url == null && name.startsWith("/"))
{
if (Log.isDebugEnabled())
Log.debug("HACK leading / off " + name);
url= this.findResource(name.substring(1));
}
}
if (url == null && !tried_parent)
{
if (_parent!=null)
url= _parent.getResource(name);
}
if (url != null)
if (Log.isDebugEnabled())
Log.debug("getResource("+name+")=" + url);
return url;
}
/* ------------------------------------------------------------ */
public boolean isServerPath(String name)
{
name=name.replace('/','.');
while(name.startsWith("."))
name=name.substring(1);
String[] server_classes = _context.getServerClasses();
if (server_classes!=null)
{
for (int i=0;i<server_classes.length;i++)
{
boolean result=true;
String c=server_classes[i];
if (c.startsWith("-"))
{
c=c.substring(1); // TODO cache
result=false;
}
if (c.endsWith("."))
{
if (name.startsWith(c))
return result;
}
else if (name.equals(c))
return result;
}
}
return false;
}
/* ------------------------------------------------------------ */
public boolean isSystemPath(String name)
{
name=name.replace('/','.');
while(name.startsWith("."))
name=name.substring(1);
String[] system_classes = _context.getSystemClasses();
if (system_classes!=null)
{
for (int i=0;i<system_classes.length;i++)
{
boolean result=true;
String c=system_classes[i];
if (c.startsWith("-"))
{
c=c.substring(1); // TODO cache
result=false;
}
if (c.endsWith("."))
{
if (name.startsWith(c))
return result;
}
else if (name.equals(c))
return result;
}
}
return false;
}
/* ------------------------------------------------------------ */
public synchronized Class loadClass(String name) throws ClassNotFoundException
{
return loadClass(name, false);
}
/* ------------------------------------------------------------ */
protected synchronized Class loadClass(String name, boolean resolve) throws ClassNotFoundException
{
Class c= findLoadedClass(name);
ClassNotFoundException ex= null;
boolean tried_parent= false;
if (c == null && _parent!=null && (_context.isParentLoaderPriority() || isSystemPath(name)) )
{
tried_parent= true;
try
{
c= _parent.loadClass(name);
if (Log.isDebugEnabled())
Log.debug("loaded " + c);
}
catch (ClassNotFoundException e)
{
ex= e;
}
}
if (c == null)
{
try
{
c= this.findClass(name);
}
catch (ClassNotFoundException e)
{
ex= e;
}
}
if (c == null && _parent!=null && !tried_parent && !isServerPath(name) )
c= _parent.loadClass(name);
if (c == null)
throw ex;
if (resolve)
resolveClass(c);
if (Log.isDebugEnabled())
Log.debug("loaded " + c+ " from "+c.getClassLoader());
return c;
}
/* ------------------------------------------------------------ */
public String toString()
{
if (Log.isDebugEnabled())
return "ContextLoader@" + _name + "(" + LazyList.array2List(getURLs()) + ") / " + _parent;
return "ContextLoader@" + _name;
}
}