WebappLoader (Apache Tomcat 7.0.109 API Documentation)

java.lang.Object
- org.apache.catalina.util.LifecycleBase
- - org.apache.catalina.util.LifecycleMBeanBase
  - - org.apache.catalina.loader.WebappLoader

All Implemented Interfaces:

PropertyChangeListener, EventListener, MBeanRegistration, JmxEnabled, Lifecycle, Loader

Direct Known Subclasses:

VirtualWebappLoader
```
public class WebappLoader
extends LifecycleMBeanBase
implements 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.

Author:

Craig R. McClanahan, Remy Maucherat

Nested Class Summary
- Nested classes/interfaces inherited from interface org.apache.catalina.Lifecycle
  Lifecycle.SingleUse

Field Summary

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

Fields inherited from class org.apache.catalina.util.LifecycleMBeanBase
mserver

Fields inherited from interface org.apache.catalina.Lifecycle
AFTER_DESTROY_EVENT, AFTER_INIT_EVENT, AFTER_START_EVENT, AFTER_STOP_EVENT, BEFORE_DESTROY_EVENT, BEFORE_INIT_EVENT, BEFORE_START_EVENT, BEFORE_STOP_EVENT, CONFIGURE_START_EVENT, CONFIGURE_STOP_EVENT, PERIODIC_EVENT, START_EVENT, STOP_EVENT

Constructor Summary

Constructors
Constructor and Description
`WebappLoader()` Construct a new WebappLoader.
`WebappLoader(ClassLoader parent)` Deprecated. Use `Container.setParentClassLoader(ClassLoader)` to specify the required class loader. This method will be removed in Tomcat 10 onwards.

Method Summary

Methods
Modifier and Type	Method and Description
`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`	`backgroundProcess()` Execute a periodic task, such as reloading, etc.
`void`	`closeJARs(boolean force)` Used to periodically signal to the classloader to release JAR resources.
`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.
`boolean`	`getDelegate()` Return the "follow standard delegation model" flag used to configure our ClassLoader.
`protected String`	`getDomainInternal()` Method implemented by sub-classes to identify the domain in which MBeans should be registered.
`String`	`getInfo()` Return descriptive information about this Loader implementation and the corresponding version number, in the format `<description>/<version>`.
`int`	`getJarOpenInterval()` Return the interval to keep all jar files open if no jar is accessed
`String`	`getLoaderClass()` Return the ClassLoader class name.
`String[]`	`getLoaderRepositories()`
`String`	`getLoaderRepositoriesString()`
`protected String`	`getObjectNameKeyProperties()` Allow sub-classes to specify the key properties component of the `ObjectName` that will be used to register this component.
`boolean`	`getReloadable()` Return the reloadable flag for this Loader.
`String[]`	`getRepositories()`
`String`	`getRepositoriesString()` Extra repositories for this loader
`boolean`	`getSearchExternalFirst()`
`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`	`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`	`setDelegate(boolean delegate)` Set the "follow standard delegation model" flag used to configure our ClassLoader.
`void`	`setJarOpenInterval(int jarOpenInterval)` The interval to keep all jar files open if no jar is accessed
`void`	`setLoaderClass(String loaderClass)` Set the ClassLoader class name.
`void`	`setReloadable(boolean reloadable)` Set the reloadable flag for this Loader.
`void`	`setSearchExternalFirst(boolean searchExternalFirst)`
`protected void`	`startInternal()` Start associated `ClassLoader` and implement the requirements of `LifecycleBase.startInternal()`.
`protected void`	`stopInternal()` Stop associated `ClassLoader` and implement the requirements of `LifecycleBase.stopInternal()`.
`String`	`toString()` Return a String representation of this component.

Methods inherited from class org.apache.catalina.util.LifecycleMBeanBase
destroyInternal, getDomain, getObjectName, initInternal, postDeregister, postRegister, preDeregister, preRegister, register, setDomain, unregister

Methods inherited from class org.apache.catalina.util.LifecycleBase
addLifecycleListener, destroy, findLifecycleListeners, fireLifecycleEvent, getState, getStateName, getThrowOnFailure, init, removeLifecycleListener, setState, setState, setThrowOnFailure, start, stop

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

- Field Detail
  - 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. The parent class loader will be defined by Container.getParentClassLoader().
  - WebappLoader
```
@Deprecated
public WebappLoader(ClassLoader parent)
```
    Deprecated. Use Container.setParentClassLoader(ClassLoader) to specify the required class loader. This method will be removed in Tomcat 10 onwards.
    
    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
    
    Returns:
    the Java class loader to be used by this Container.
  - getContainer
```
public Container getContainer()
```
    Return the Container with which this Logger has been associated.
    
    Specified by:
    
    getContainer in interface Loader
    
    Returns:
    the Container with which this Loader has been associated.
  - 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
  - getDelegate
```
public boolean getDelegate()
```
    Return the "follow standard delegation model" flag used to configure our ClassLoader.
    
    Specified by:
    
    getDelegate in interface Loader
    
    Returns:
    the "follow standard delegation model" flag used to configure our ClassLoader.
  - 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
  - setJarOpenInterval
```
public void setJarOpenInterval(int jarOpenInterval)
```
    The interval to keep all jar files open if no jar is accessed
    
    Parameters:
    jarOpenInterval - The new interval
  - getJarOpenInterval
```
public int getJarOpenInterval()
```
    Return the interval to keep all jar files open if no jar is accessed
  - 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
    
    Returns:
    descriptive information about this Loader implementation and the corresponding version number, in the format <description>/<version>.
  - 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
    
    Returns:
    the reloadable flag for this 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
  - getSearchExternalFirst
```
public boolean getSearchExternalFirst()
```
    Returns:
    Returns searchExternalFirst.
  - setSearchExternalFirst
```
public void setSearchExternalFirst(boolean searchExternalFirst)
```
    Parameters:
    searchExternalFirst - Whether external repositories should be searched first
  - 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
  - backgroundProcess
```
public void backgroundProcess()
```
    Execute a periodic task, such as reloading, etc. This method will be invoked inside the classloading context of this container. Unexpected throwables will be caught and logged.
    
    Specified by:
    
    backgroundProcess in interface Loader
  - 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
    
    Returns:
    the set of repositories defined for this class loader. If none are defined, a zero-length array is returned.
  - getRepositories
```
public String[] getRepositories()
```
  - getRepositoriesString
```
public String getRepositoriesString()
```
    Extra repositories for this loader
  - getLoaderRepositories
```
public String[] getLoaderRepositories()
```
  - getLoaderRepositoriesString
```
public String getLoaderRepositoriesString()
```
  - 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
    
    Returns:
    true when the repository has been modified, false otherwise
  - 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
  - startInternal
```
protected void startInternal()
                      throws LifecycleException
```
    Start associated ClassLoader and implement the requirements of LifecycleBase.startInternal().
    
    Specified by:
    
    startInternal in class LifecycleBase
    
    Throws:
    
    LifecycleException - if this component detects a fatal error that prevents this component from being used
  - stopInternal
```
protected void stopInternal()
                     throws LifecycleException
```
    Stop associated ClassLoader and implement the requirements of LifecycleBase.stopInternal().
    
    Specified by:
    
    stopInternal in class LifecycleBase
    
    Throws:
    
    LifecycleException - if this component detects a fatal error that prevents this component from being used
  - 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
  - getDomainInternal
```
protected String getDomainInternal()
```
    Description copied from class: LifecycleMBeanBase
    
    Method implemented by sub-classes to identify the domain in which MBeans should be registered.
    
    Specified by:
    
    getDomainInternal in class LifecycleMBeanBase
    
    Returns:
    The name of the domain to use to register MBeans.
  - getObjectNameKeyProperties
```
protected String getObjectNameKeyProperties()
```
    Description copied from class: LifecycleMBeanBase
    
    Allow sub-classes to specify the key properties component of the ObjectName that will be used to register this component.
    
    Specified by:
    
    getObjectNameKeyProperties in class LifecycleMBeanBase
    
    Returns:
    The string representation of the key properties component of the desired ObjectName

Class WebappLoader

Nested Class Summary

Nested classes/interfaces inherited from interface org.apache.catalina.Lifecycle

Field Summary

Fields inherited from class org.apache.catalina.util.LifecycleMBeanBase

Fields inherited from interface org.apache.catalina.Lifecycle

Constructor Summary

Method Summary

Methods inherited from class org.apache.catalina.util.LifecycleMBeanBase

Methods inherited from class org.apache.catalina.util.LifecycleBase

Methods inherited from class java.lang.Object

Field Detail

sm

support

Constructor Detail

WebappLoader

WebappLoader

Method Detail

getClassLoader

getContainer

setContainer

getDelegate

setDelegate

setJarOpenInterval

getJarOpenInterval

getInfo

getLoaderClass

setLoaderClass

getReloadable

setReloadable

getSearchExternalFirst

setSearchExternalFirst

addPropertyChangeListener

addRepository

backgroundProcess

findRepositories

getRepositories

getRepositoriesString

getLoaderRepositories

getLoaderRepositoriesString

getClasspath

modified

closeJARs

removePropertyChangeListener

toString

startInternal

stopInternal

propertyChange

getDomainInternal

getObjectNameKeyProperties