org.apache.catalina.loader

Class WebappLoader

java.lang.Object

org.apache.catalina.loader.WebappLoader

All Implemented Interfaces:

PropertyChangeListener, EventListener, Lifecycle, Loader

public class WebappLoader
extends Object
implements Lifecycle, Loader, PropertyChangeListener

Classloader implementation which is specialized for handling web applications in the most efficient way, while being Catalina aware (all accesses to resources are made through the DirContext interface). This class loader supports detection of modified Java classes, which can be used to implement auto-reload support.

This class loader is configured by adding the pathnames of directories, JAR files, and ZIP files with the addRepository() method, prior to calling start(). When a new class is required, these repositories will be consulted first to locate the class. If it is not present, the system class loader will be used instead.

Version:

$Revision: 1.10 $ $Date: 2007/05/05 05:32:09 $

Author:

Craig R. McClanahan, Remy Maucherat

Field Summary

Fields

Modifier and Type	Field and Description
protected LifecycleSupport	lifecycle The lifecycle event support for this component.
protected static StringManager	sm The string manager for this package.
protected PropertyChangeSupport	support The property change support for this component.

Fields inherited from interface org.apache.catalina.Lifecycle

AFTER_START_EVENT, AFTER_STOP_EVENT, BEFORE_START_EVENT, BEFORE_STOP_EVENT, INIT_EVENT, START_EVENT, STOP_EVENT

Constructor Summary

Constructors

Constructor and Description
WebappLoader() Construct a new WebappLoader with no defined parent class loader (so that the actual parent will be the system class loader).
WebappLoader(ClassLoader parent) Construct a new WebappLoader with the specified class loader to be defined as the parent of the ClassLoader we ultimately create.

Method Summary

Modifier and Type	Method and Description
void	addLifecycleListener(LifecycleListener listener) Add a lifecycle event listener to this component.
void	addOverridablePackage(String packageName) Adds the given package name to the list of packages that may always be overriden, regardless of whether they belong to a protected namespace
void	addPropertyChangeListener(PropertyChangeListener listener) Add a property change listener to this component.
void	addRepository(String repository) Add a new repository to the set of repositories for this class loader.
void	closeJARs(boolean force) Used to periodically signal to the classloader to release JAR resources.
protected ClassLoader	createClassLoader() Create associated classLoader.
void	destroy()
List<LifecycleListener>	findLifecycleListeners() Gets the (possibly empty) list of lifecycle listeners associated with this WebappLoader.
String[]	findRepositories() Return the set of repositories defined for this class loader.
ClassLoader	getClassLoader() Return the Java class loader to be used by this Container.
String	getClasspath() Classpath, as set in org.apache.catalina.jsp_classpath context property
Container	getContainer() Return the Container with which this Logger has been associated.
ObjectName	getController()
int	getDebug() Return the debugging detail level for this component.
boolean	getDelegate() Return the "follow standard delegation model" flag used to configure our ClassLoader.
String	getInfo() Return descriptive information about this Loader implementation and the corresponding version number, in the format <description>/<version>.
String	getLoaderClass() Return the ClassLoader class name.
boolean	getReloadable() Return the reloadable flag for this Loader.
String[]	getRepositories()
void	init()
boolean	modified() Has the internal repository associated with this Loader been modified, such that the loaded classes should be reloaded?
void	propertyChange(PropertyChangeEvent event) Process property change events from our associated Context.
void	removeLifecycleListener(LifecycleListener listener) Remove a lifecycle event listener from this component.
void	removePropertyChangeListener(PropertyChangeListener listener) Remove a property change listener from this component.
void	setContainer(Container container) Set the Container with which this Logger has been associated.
void	setController(ObjectName controller)
void	setDebug(int debug) Set the debugging detail level for this component.
void	setDelegate(boolean delegate) Set the "follow standard delegation model" flag used to configure our ClassLoader.
void	setIgnoreHiddenJarFiles(boolean ignoreHiddenJarFiles)
void	setLoaderClass(String loaderClass) Set the ClassLoader class name.
void	setReloadable(boolean reloadable) Set the reloadable flag for this Loader.
void	setUseMyFaces(boolean useMyFaces)
void	start() Start this component, initializing our associated class loader.
void	stop() Stop this component, finalizing our associated class loader.
void	stopNestedClassLoader() Stops the nested classloader
String	toString() Return a String representation of this component.

Methods inherited from class java.lang.Object

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

Field Detail

lifecycle

protected LifecycleSupport lifecycle

The lifecycle event support for this component.

sm

protected static final StringManager sm

The string manager for this package.

support

protected PropertyChangeSupport support

The property change support for this component.

Constructor Detail

WebappLoader

public WebappLoader()

Construct a new WebappLoader with no defined parent class loader (so that the actual parent will be the system class loader).

WebappLoader

public WebappLoader(ClassLoader parent)

Construct a new WebappLoader with the specified class loader to be defined as the parent of the ClassLoader we ultimately create.

Parameters:

parent - The parent class loader

Method Detail

getClassLoader

public ClassLoader getClassLoader()

Return the Java class loader to be used by this Container.

Specified by:

getClassLoader in interface Loader

getContainer

public Container getContainer()

Return the Container with which this Logger has been associated.

Specified by:

getContainer in interface Loader

setContainer

public void setContainer(Container container)

Set the Container with which this Logger has been associated.

Specified by:

setContainer in interface Loader

Parameters:

container - The associated Container

getDebug

public int getDebug()

Return the debugging detail level for this component.

setDebug

public void setDebug(int debug)

Set the debugging detail level for this component.

Parameters:

debug - The new debugging detail level

getDelegate

public boolean getDelegate()

Return the "follow standard delegation model" flag used to configure our ClassLoader.

Specified by:

getDelegate in interface Loader

setDelegate

public void setDelegate(boolean delegate)

Set the "follow standard delegation model" flag used to configure our ClassLoader.

Specified by:

setDelegate in interface Loader

Parameters:

delegate - The new flag

getInfo

public String getInfo()

Return descriptive information about this Loader implementation and the corresponding version number, in the format <description>/<version>.

Specified by:

getInfo in interface Loader

getLoaderClass

public String getLoaderClass()

Return the ClassLoader class name.

setLoaderClass

public void setLoaderClass(String loaderClass)

Set the ClassLoader class name.

Parameters:

loaderClass - The new ClassLoader class name

getReloadable

public boolean getReloadable()

Return the reloadable flag for this Loader.

Specified by:

getReloadable in interface Loader

setReloadable

public void setReloadable(boolean reloadable)

Set the reloadable flag for this Loader.

Specified by:

setReloadable in interface Loader

Parameters:

reloadable - The new reloadable flag

setUseMyFaces

public void setUseMyFaces(boolean useMyFaces)

addPropertyChangeListener

public void addPropertyChangeListener(PropertyChangeListener listener)

Add a property change listener to this component.

Specified by:

addPropertyChangeListener in interface Loader

Parameters:

listener - The listener to add

addRepository

public void addRepository(String repository)

Add a new repository to the set of repositories for this class loader.

Specified by:

addRepository in interface Loader

Parameters:

repository - Repository to be added

findRepositories

public String[] findRepositories()

Return the set of repositories defined for this class loader. If none are defined, a zero-length array is returned. For security reason, returns a clone of the Array (since String are immutable).

Specified by:

findRepositories in interface Loader

getRepositories

public String[] getRepositories()

getClasspath

public String getClasspath()

Classpath, as set in org.apache.catalina.jsp_classpath context property

Returns:

The classpath

modified

public boolean modified()

Has the internal repository associated with this Loader been modified, such that the loaded classes should be reloaded?

Specified by:

modified in interface Loader

closeJARs

public void closeJARs(boolean force)

Used to periodically signal to the classloader to release JAR resources.

removePropertyChangeListener

public void removePropertyChangeListener(PropertyChangeListener listener)

Remove a property change listener from this component.

Specified by:

removePropertyChangeListener in interface Loader

Parameters:

listener - The listener to remove

toString

public String toString()

Return a String representation of this component.

Overrides:

toString in class Object

addLifecycleListener

public void addLifecycleListener(LifecycleListener listener)

Add a lifecycle event listener to this component.

Specified by:

addLifecycleListener in interface Lifecycle

Parameters:

listener - The listener to add

findLifecycleListeners

public List<LifecycleListener> findLifecycleListeners()

Gets the (possibly empty) list of lifecycle listeners associated with this WebappLoader.

Specified by:

findLifecycleListeners in interface Lifecycle

removeLifecycleListener

public void removeLifecycleListener(LifecycleListener listener)

Remove a lifecycle event listener from this component.

Specified by:

removeLifecycleListener in interface Lifecycle

Parameters:

listener - The listener to remove

init

public void init()

destroy

public void destroy()

start

public void start()
           throws LifecycleException

Start this component, initializing our associated class loader.

Specified by:

start in interface Lifecycle

Throws:

LifecycleException - if a lifecycle error occurs

stop

public void stop()
          throws LifecycleException

Stop this component, finalizing our associated class loader.

Specified by:

stop in interface Lifecycle

Throws:

LifecycleException - if a lifecycle error occurs

stopNestedClassLoader

public void stopNestedClassLoader()
                           throws LifecycleException

Stops the nested classloader

Throws:

LifecycleException

propertyChange

public void propertyChange(PropertyChangeEvent event)

Process property change events from our associated Context.

Specified by:

propertyChange in interface PropertyChangeListener

Parameters:

event - The property change event that has occurred

createClassLoader

protected ClassLoader createClassLoader()
                                 throws Exception

Create associated classLoader.

Throws:

Exception

getController

public ObjectName getController()

setController

public void setController(ObjectName controller)

addOverridablePackage

public void addOverridablePackage(String packageName)

Adds the given package name to the list of packages that may always be overriden, regardless of whether they belong to a protected namespace

Specified by:

addOverridablePackage in interface Loader

setIgnoreHiddenJarFiles

public void setIgnoreHiddenJarFiles(boolean ignoreHiddenJarFiles)

Specified by:

setIgnoreHiddenJarFiles in interface Loader