org.hotswap.agent.util.classloader

Class ClassLoaderDefineClassPatcher

java.lang.Object

org.hotswap.agent.util.classloader.ClassLoaderDefineClassPatcher

All Implemented Interfaces:

ClassLoaderPatcher

public class ClassLoaderDefineClassPatcher
extends Object
implements ClassLoaderPatcher

Classloader patch which will redefine each patch via Javassist in the target classloader.

Note that the class will typically be already accessible by parent classloader, but if it is loaded from parent classloader, it does not have access to other child classloader classes.

Redefine will work only if the class was not loaded by the child classloader. This may not be used for Plugin class itself, because some target library classes may be enhanced by plugin reference (e.g. to set some initialized property). Although the class resides in parent classloader it cannot be redefined in child classloader with other definition - the classloader already knows about this class. This is the reason, why plugin class cannot be executed in child classloader.

Author:

Jiri Bubnik

Constructor Summary

Constructors

Constructor and Description
ClassLoaderDefineClassPatcher()

Method Summary

Modifier and Type	Method and Description
boolean	isPatchAvailable(ClassLoader classLoader) Check if the classloader can be patched.
void	patch(ClassLoader classLoaderFrom, String pluginPath, ClassLoader classLoaderTo, ProtectionDomain protectionDomain) Patch the classloader.

Methods inherited from class java.lang.Object

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

Constructor Detail

ClassLoaderDefineClassPatcher

public ClassLoaderDefineClassPatcher()

Method Detail

patch

public void patch(ClassLoader classLoaderFrom,
                  String pluginPath,
                  ClassLoader classLoaderTo,
                  ProtectionDomain protectionDomain)

Description copied from interface: ClassLoaderPatcher

Patch the classloader.

Specified by:

patch in interface ClassLoaderPatcher

Parameters:

classLoaderFrom - classloader to load classes from

pluginPath - path to copy

classLoaderTo - classloader to copy classes to

protectionDomain - required protection in target classloader

isPatchAvailable

public boolean isPatchAvailable(ClassLoader classLoader)

Description copied from interface: ClassLoaderPatcher

Check if the classloader can be patched. Typically skip synthetic classloaders.

Specified by:

isPatchAvailable in interface ClassLoaderPatcher

Parameters:

classLoader - classloader to check

Returns:

if true, call patch()