org.jboss.aop.standalone
Class SystemClassLoader

java.lang.Object
  java.lang.ClassLoader
      org.jboss.aop.standalone.SystemClassLoader

public class SystemClassLoader
extends ClassLoader

A classloader that can be installed as the system classloader to enable aop translation based on files in META-INF/jboss-aop.xml in the classpath.

You will need the following jars in your classpath (log4j.jar is optional):

• jboss-aop.jar
• javassist.jar
• jboss-common.jar

Start the virtual machine with something like the following command:

 java -Djava.system.class.loader=org.jboss.aop.standalone.SystemClassLoader my.Main
 

Implementation Detail: All access to non-jre classes must be done through reflection the classes must be loaded using the loadLocally method.

Version:

$Revision: 71279 $

Author:

Adrian Brock, Juha Lindfors

Constructor Summary

SystemClassLoader(ClassLoader parent)
Construct a new system classloader.

Method Summary

protected Class<?>	defineClassFromBytes(String name, org.jboss.aop.standalone.SystemClassLoader.ClassBytes bytes, boolean resolve) Define a class from the bytes
protected void	definePackage(String className) Define the package for the class if not already done
protected void	initialize() Initialize the aspect manager and load the static aspects
protected void	install() Install the classloader, get reflection objects and load classes using ourself.
Class<?>	loadClass(String name, boolean resolve) Load a class, overridden to transform aop enhanced classes and load non jre classes through this classloader.
protected Class<?>	loadClassByDelegation(String name) Load jre classes from the parent classloader
protected org.jboss.aop.standalone.SystemClassLoader.ClassBytes	loadClassBytes(String name) Load the bytecode for a class
protected Class<?>	loadClassLocally(String name) Load a class using this classloader only

Methods inherited from class java.lang.ClassLoader

clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findClass, findLibrary, findLoadedClass, findResource, findResources, findSystemClass, getPackage, getPackages, getParent, getResource, getResourceAsStream, getResources, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, loadClass, resolveClass, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SystemClassLoader

public SystemClassLoader(ClassLoader parent)

Construct a new system classloader.

We cannot do much here, we need to avoid recursion

Parameters:

parent - the default system classloader

Method Detail

loadClass

public Class<?> loadClass(String name,
                          boolean resolve)
                   throws ClassNotFoundException

Load a class, overridden to transform aop enhanced classes and load non jre classes through this classloader.

Overrides:

loadClass in class ClassLoader

Parameters:

name - the class name

resolve - whether to resolve the class

Returns:

the class

Throws:

ClassNotFoundException - when there is no class

loadClassBytes

protected org.jboss.aop.standalone.SystemClassLoader.ClassBytes loadClassBytes(String name)
                                                                        throws ClassNotFoundException,
                                                                               IOException

Load the bytecode for a class

Throws:

ClassNotFoundException

IOException

defineClassFromBytes

protected Class<?> defineClassFromBytes(String name,
                                        org.jboss.aop.standalone.SystemClassLoader.ClassBytes bytes,
                                        boolean resolve)

Define a class from the bytes

Parameters:

b - the bytecode

resolve - whether to resolve the class

definePackage

protected void definePackage(String className)

Define the package for the class if not already done

Parameters:

name - the class name

loadClassLocally

protected Class<?> loadClassLocally(String name)
                             throws ClassNotFoundException

Load a class using this classloader only

Parameters:

name - the class name

Returns:

the class

Throws:

ClassNotFoundException - when there is no class

loadClassByDelegation

protected Class<?> loadClassByDelegation(String name)
                                  throws ClassNotFoundException

Load jre classes from the parent classloader

Parameters:

name - the class name

Returns:

the class

Throws:

ClassNotFoundException - when there is no class

install

protected void install()

Install the classloader, get reflection objects and load classes using ourself.

initialize

protected void initialize()

Initialize the aspect manager and load the static aspects