org.jboss.mx.loading
Class RepositoryClassLoader

java.lang.Object
  java.lang.ClassLoader
      java.security.SecureClassLoader
          java.net.URLClassLoader
              org.jboss.mx.loading.RepositoryClassLoader

All Implemented Interfaces:

org.jboss.classloading.spi.RealClassLoader, org.jboss.util.loading.Translatable

Direct Known Subclasses:

UnifiedClassLoader

public abstract class RepositoryClassLoader
extends URLClassLoader
implements org.jboss.classloading.spi.RealClassLoader

A RepositoryClassLoader.

Version:

$Revision: 86129 $

Author:

Adrian Brock

Field Summary

protected int	loadClassDepth A debugging variable used to track the recursive depth of loadClass()
protected ReentrantLock	loadLock Lock
protected ClassLoader	parent The parent classloader
protected LoaderRepository	repository Reference to the repository.
protected Exception	unregisterTrace The location where unregister is called from

Constructor Summary

protected

RepositoryClassLoader(URL[] urls, ClassLoader parent) Create a new LoaderRepositoryClassLoader

Method Summary

protected void	acquire() Acquire the class loading lock.
void	addToClassBlackList(String name) Black list a class
void	addToResourceBlackList(String name) Black list a resource
void	addURL(URL url) Append the given url to the URLs used for class and resource loading
protected boolean	attempt(long waitMS) Attempt to acquire the class loading lock.
void	clearBlackList(String name)
void	clearBlacklists() Clear all blacklists
void	clearClassBlackList() Clear any class black list.
void	clearResourceBlackList() Clear any resource blacklist.
protected void	definePackage(String className) Define the package for the class if not already done
boolean	equals(Object other) This is here to document that this must delegate to the super implementation to perform identity based equality.
protected Class<?>	findClass(String name) Called by loadClassLocally to find the requested class within this class loaders class path.
protected Class<?>	findClassLocally(String name) Find the class
Enumeration<URL>	findResources(String name) Find all resource URLs for the given name.
Enumeration<URL>	findResourcesLocally(String name) Provides the same functionality as URLClassLoader.findResources(java.lang.String).
int	getAddedOrder() Get the order this classloader was added to the repository
URL[]	getAllURLs() Return all library URLs associated with this RepositoryClassLoader
Class<?>	getCachedClass(String name)
URL	getCachedResource(String name)
URL[]	getClasspath() This method simply invokes the super.getURLs() method to access the list of URLs that make up the RepositoryClassLoader classpath.
LoaderRepository	getLoaderRepository() Get the loader repository for this classloader
abstract ObjectName	getObjectName() Get the ObjectName
Package	getPackage(String name)
Package[]	getPackages()
protected ProtectionDomain	getProtectionDomain(URL codesourceUrl) Determine the protection domain.
URL	getResource(String name) Attempts to load the resource from its URL and if not found forwards to the request to LoaderRepository.
URL	getResourceLocally(String name)
URL	getURL() Get the URL associated with the UCL.
URL[]	getURLs() Return an empty URL array to force the RMI marshalling subsystem to use the java.server.codebase property as the annotated codebase.
int	hashCode() This is here to document that this must delegate to the super implementation to perform identity based hashing.
boolean	isClassBlackListed(String name) Is the class black listed?
boolean	isResourceBlackListed(String name) Is the resource black listed?
boolean	isValid()
protected byte[]	loadByteCode(String classname) Obtain the bytecode for the indicated class from this class loaders classpath.
protected byte[]	loadByteCode(URL classURL) Obtain the bytecode for the indicated class from this class loaders classpath.
Class<?>	loadClass(String name, boolean resolve) The only caller of this method should be the VM initiated loadClassInternal() method.
Class<?>	loadClassBefore(String name) The only caller of this method should be the VM initiated loadClassInternal() method.
abstract Class<?>	loadClassImpl(String name, boolean resolve, int stopAt)
Class<?>	loadClassLocally(String name, boolean resolve)
protected void	release() Release the class loading lock previous acquired through the acquire method.
void	removeFromClassBlackList(String name) Remove class from black list
void	removeFromResourceBlackList(String name) Remove resource from black list
void	setAddedOrder(int addedOrder) Set the order this classloader was added to the repository
void	setRepository(LoaderRepository repository) Set the loader repository
String	toString() Returns a string representation.
void	unregister()

Methods inherited from class java.net.URLClassLoader

definePackage, findResource, getPermissions, newInstance, newInstance

Methods inherited from class java.security.SecureClassLoader

defineClass, defineClass

Methods inherited from class java.lang.ClassLoader

clearAssertionStatus, defineClass, defineClass, defineClass, defineClass, definePackage, findLibrary, findLoadedClass, findSystemClass, getParent, getResourceAsStream, getResources, getSystemClassLoader, getSystemResource, getSystemResourceAsStream, getSystemResources, loadClass, resolveClass, setClassAssertionStatus, setDefaultAssertionStatus, setPackageAssertionStatus, setSigners

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

repository

protected LoaderRepository repository

Reference to the repository.

unregisterTrace

protected Exception unregisterTrace

The location where unregister is called from

parent

protected ClassLoader parent

The parent classloader

loadLock

protected ReentrantLock loadLock

Lock

loadClassDepth

protected int loadClassDepth

A debugging variable used to track the recursive depth of loadClass()

Constructor Detail

RepositoryClassLoader

protected RepositoryClassLoader(URL[] urls,
                                ClassLoader parent)

Create a new LoaderRepositoryClassLoader

Parameters:

urls - the urls

parent - the parent classloader

Method Detail

getObjectName

public abstract ObjectName getObjectName()

Get the ObjectName

Specified by:

getObjectName in interface org.jboss.classloading.spi.RealClassLoader

Returns:

the object name

isValid

public boolean isValid()

Specified by:

isValid in interface org.jboss.classloading.spi.RealClassLoader

getLoaderRepository

public LoaderRepository getLoaderRepository()

Get the loader repository for this classloader

Returns:

the loader repository

setRepository

public void setRepository(LoaderRepository repository)

Set the loader repository

Parameters:

repository - the repository

getCachedClass

public Class<?> getCachedClass(String name)

Specified by:

getCachedClass in interface org.jboss.classloading.spi.RealClassLoader

getCachedResource

public URL getCachedResource(String name)

Specified by:

getCachedResource in interface org.jboss.classloading.spi.RealClassLoader

clearBlackList

public void clearBlackList(String name)

Specified by:

clearBlackList in interface org.jboss.classloading.spi.RealClassLoader

getAddedOrder

public int getAddedOrder()

Get the order this classloader was added to the repository

Returns:

the order

setAddedOrder

public void setAddedOrder(int addedOrder)

Set the order this classloader was added to the repository

Parameters:

addedOrder - the added order

loadClassLocally

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

Throws:

ClassNotFoundException

getResourceLocally

public URL getResourceLocally(String name)

Specified by:

getResourceLocally in interface org.jboss.util.loading.Translatable

getURL

public URL getURL()

Get the URL associated with the UCL.

Returns:

the url

unregister

public void unregister()

getClasspath

public URL[] getClasspath()

This method simply invokes the super.getURLs() method to access the list of URLs that make up the RepositoryClassLoader classpath.

Returns:

the urls that make up the classpath

getAllURLs

public URL[] getAllURLs()

Return all library URLs associated with this RepositoryClassLoader

Do not remove this method without running the WebIntegrationTestSuite

Returns:

the urls

addToClassBlackList

public void addToClassBlackList(String name)

Black list a class

Parameters:

name - the name of the class

removeFromClassBlackList

public void removeFromClassBlackList(String name)

Remove class from black list

Parameters:

name - the name of the class

isClassBlackListed

public boolean isClassBlackListed(String name)

Is the class black listed?

Parameters:

name - the name of the class

Returns:

true when the class is black listed, false otherwise

clearClassBlackList

public void clearClassBlackList()

Clear any class black list.

addToResourceBlackList

public void addToResourceBlackList(String name)

Black list a resource

Parameters:

name - the name of the resource

removeFromResourceBlackList

public void removeFromResourceBlackList(String name)

Remove resource from black list

Parameters:

name - the name of the resource

isResourceBlackListed

public boolean isResourceBlackListed(String name)

Is the resource black listed?

Parameters:

name - the name of the resource

Returns:

true when the resource is black listed, false otherwise

clearResourceBlackList

public void clearResourceBlackList()

Clear any resource blacklist.

clearBlacklists

public void clearBlacklists()

Clear all blacklists

loadClass

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

The only caller of this method should be the VM initiated loadClassInternal() method. This method attempts to acquire the UnifiedLoaderRepository2 lock and then asks the repository to load the class.

Forwards request to LoaderRepository.

Overrides:

loadClass in class ClassLoader

Throws:

ClassNotFoundException

loadClassBefore

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

The only caller of this method should be the VM initiated loadClassInternal() method. This method attempts to acquire the UnifiedLoaderRepository2 lock and then asks the repository to load the class.

Forwards request to LoaderRepository.

Parameters:

name - the class name

Returns:

the class

Throws:

ClassNotFoundException - when the class is not found

loadClassImpl

public abstract Class<?> loadClassImpl(String name,
                                       boolean resolve,
                                       int stopAt)
                                throws ClassNotFoundException

Throws:

ClassNotFoundException

getResource

public URL getResource(String name)

Attempts to load the resource from its URL and if not found forwards to the request to LoaderRepository.

Overrides:

getResource in class ClassLoader

findResources

public Enumeration<URL> findResources(String name)
                               throws IOException

Find all resource URLs for the given name. This overrides the URLClassLoader version to look for resources in the repository.

Overrides:

findResources in class URLClassLoader

Parameters:

name - the name of the resource

Returns:

Enumeration

Throws:

IOException

findResourcesLocally

public Enumeration<URL> findResourcesLocally(String name)
                                      throws IOException

Provides the same functionality as URLClassLoader.findResources(java.lang.String).

Parameters:

name - the resource name

Returns:

the found resources

Throws:

IOException - for an error accessing the resources

findClass

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

Called by loadClassLocally to find the requested class within this class loaders class path.

Overrides:

findClass in class URLClassLoader

Parameters:

name - the name of the class

Returns:

the resulting class

Throws:

ClassNotFoundException - if the class could not be found

findClassLocally

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

Find the class

Parameters:

name - the name of the class

Returns:

the class

Throws:

ClassNotFoundException - when the class is not found

definePackage

protected void definePackage(String className)

Define the package for the class if not already done

Parameters:

className - the class name

addURL

public void addURL(URL url)

Append the given url to the URLs used for class and resource loading

Overrides:

addURL in class URLClassLoader

Parameters:

url - the URL to load from

getURLs

public URL[] getURLs()

Return an empty URL array to force the RMI marshalling subsystem to use the java.server.codebase property as the annotated codebase.

Do not remove this method without discussing it on the dev list.

Overrides:

getURLs in class URLClassLoader

Returns:

Empty URL[]

getPackage

public Package getPackage(String name)

Overrides:

getPackage in class ClassLoader

getPackages

public Package[] getPackages()

Overrides:

getPackages in class ClassLoader

equals

public final boolean equals(Object other)

This is here to document that this must delegate to the super implementation to perform identity based equality. Using URL based equality caused conflicts with the Class.forName(String, boolean, ClassLoader).

Overrides:

equals in class Object

hashCode

public final int hashCode()

This is here to document that this must delegate to the super implementation to perform identity based hashing. Using URL based hashing caused conflicts with the Class.forName(String, boolean, ClassLoader).

Overrides:

hashCode in class Object

toString

public String toString()

Returns a string representation.

Overrides:

toString in class Object

attempt

protected boolean attempt(long waitMS)

Attempt to acquire the class loading lock. This lock must be acquired before a thread enters the class loading task loop in loadClass. This method maintains any interrupted state of the calling thread.

Parameters:

waitMS - the length of time to wait in milliseconds

Returns:

true when the lock was obtained

See Also:

loadClass(String, boolean)

acquire

protected void acquire()

Acquire the class loading lock. This lock must be acquired before a thread enters the class loading task loop in loadClass.

See Also:

loadClass(String, boolean)

release

protected void release()

Release the class loading lock previous acquired through the acquire method.

loadByteCode

protected byte[] loadByteCode(String classname)
                       throws ClassNotFoundException,
                              IOException

Obtain the bytecode for the indicated class from this class loaders classpath.

Parameters:

classname -

Returns:

the bytecode array if found

Throws:

ClassNotFoundException - - if the class resource could not be found

IOException - when there is an error loading the class bytes

loadByteCode

protected byte[] loadByteCode(URL classURL)
                       throws ClassNotFoundException,
                              IOException

Obtain the bytecode for the indicated class from this class loaders classpath.

Parameters:

classURL -

Returns:

the bytecode array if found

Throws:

ClassNotFoundException - - if the class resource could not be found

IOException - when there is an error loading the class bytes

getProtectionDomain

protected ProtectionDomain getProtectionDomain(URL codesourceUrl)

Determine the protection domain. If we are a copy of the original deployment, use the original url as the codebase.

Parameters:

codesourceUrl - the codesource url

Returns:

the protection domain