/*
* JBoss, Home of Professional Open Source
* Copyright 2005, JBoss Inc., and individual contributors as indicated
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.jbpm.instantiation;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLStreamHandler;
import org.jbpm.JbpmException;
import org.jbpm.file.def.FileDefinition;
import org.jbpm.graph.def.ProcessDefinition;
public class ProcessClassLoader extends ClassLoader {
private ProcessDefinition processDefinition = null;
public ProcessClassLoader( ClassLoader parent, ProcessDefinition processDefinition ) {
super(parent);
this.processDefinition = processDefinition;
}
public URL findResource(String name) {
URL url = null;
FileDefinition fileDefinition = processDefinition.getFileDefinition();
if (fileDefinition!=null) {
// if the name of the resources starts with a /
if (name.startsWith("/")) {
// then we start searching from the root of the process archive
// we know that the leading slashes are removed in the names of the
// file definitions, therefor we skip the leading slashes
while (name.startsWith("/")) {
name = name.substring(1);
}
} else {
// otherwise, (if the resource is relative), we look in the classes
// directory in the process archive
name = "classes/"+name;
}
byte[] bytes = null;
if (fileDefinition.hasFile(name)) {
bytes = fileDefinition.getBytes(name);
}
if (bytes!=null) {
try {
url = new URL(null, "processresource://"+processDefinition.getName()+"/classes/"+name, new BytesUrlStreamHandler(bytes));
} catch (MalformedURLException e) {
throw new JbpmException("couldn't create url", e);
}
}
}
return url;
}
public static class BytesUrlStreamHandler extends URLStreamHandler {
byte[] bytes;
public BytesUrlStreamHandler(byte[] bytes) {
this.bytes = bytes;
}
protected URLConnection openConnection(URL u) throws IOException {
return new BytesUrlConnection(bytes, u);
}
}
public static class BytesUrlConnection extends URLConnection {
byte[] bytes = null;
public BytesUrlConnection(byte[] bytes, URL u) {
super(u);
this.bytes = bytes;
}
public void connect() throws IOException {
}
public InputStream getInputStream() throws IOException {
return new ByteArrayInputStream(bytes);
}
}
public Class findClass(String name) throws ClassNotFoundException {
Class clazz = null;
FileDefinition fileDefinition = processDefinition.getFileDefinition();
if (fileDefinition!=null) {
String fileName = "classes/" + name.replace( '.', '/' ) + ".class";
byte[] classBytes;
try {
classBytes = fileDefinition.getBytes(fileName);
clazz = defineClass(name, classBytes, 0, classBytes.length);
} catch (JbpmException e) {
clazz = null;
}
}
if (clazz==null) {
throw new ClassNotFoundException("class '"+name+"' could not be found by the process classloader");
}
return clazz;
}
}