org.alfresco.bm.classloader.zookeeper
Class ZooKeeperClassLoader

java.lang.Object
  java.lang.ClassLoader
      org.alfresco.bm.classloader.zookeeper.ZooKeeperClassLoader

All Implemented Interfaces:

CallbackClassLoader, org.I0Itec.zkclient.IZkChildListener, org.I0Itec.zkclient.IZkDataListener

public class ZooKeeperClassLoader
extends ClassLoader
implements CallbackClassLoader, org.I0Itec.zkclient.IZkDataListener, org.I0Itec.zkclient.IZkChildListener

A Java ClassLoader pulling classes from ZooKeeper.

This class loader allows listeners to be registered to receive callbacks when the ZooKeeper data changes.

Since:

1.0

Author:

Derek Hulley

Constructor Summary

ZooKeeperClassLoader(ClassLoader parentClassloader, org.I0Itec.zkclient.ZkClient zk, String rootPath)

Method Summary

void	addListener(ClassLoaderListener listener) Add a change listener
void	handleChildChange(String parentPath, List<String> currentChilds) Calls any listeners.
void	handleDataChange(String dataPath, Object data) Calls any listeners.
void	handleDataDeleted(String dataPath) Calls any listeners.
Class<?>	loadClass(String name) Takes the rootPath variable and finds (using '/' in place of '.') the class in ZooKeeper.

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

ZooKeeperClassLoader

public ZooKeeperClassLoader(ClassLoader parentClassloader,
                            org.I0Itec.zkclient.ZkClient zk,
                            String rootPath)

Parameters:

parentClassloader - the (required) parent class loader

zk - the ZK client to run against

rootPath - the ZK root path (akin to a classpath entry)

Method Detail

handleChildChange

public void handleChildChange(String parentPath,
                              List<String> currentChilds)
                       throws Exception

Calls any listeners.

Specified by:

handleChildChange in interface org.I0Itec.zkclient.IZkChildListener

Throws:

Exception

handleDataChange

public void handleDataChange(String dataPath,
                             Object data)
                      throws Exception

Calls any listeners.

Specified by:

handleDataChange in interface org.I0Itec.zkclient.IZkDataListener

Throws:

Exception

handleDataDeleted

public void handleDataDeleted(String dataPath)
                       throws Exception

Calls any listeners.

Specified by:

handleDataDeleted in interface org.I0Itec.zkclient.IZkDataListener

Throws:

Exception

addListener

public void addListener(ClassLoaderListener listener)

Add a change listener

Specified by:

addListener in interface CallbackClassLoader

Parameters:

listener - the listener that will be called if there are any changes to classes already loaded

loadClass

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

Takes the rootPath variable and finds (using '/' in place of '.') the class in ZooKeeper.

Overrides:

loadClass in class ClassLoader

Throws:

ClassNotFoundException