org.apache.catalina
Interface Wrapper

All Superinterfaces:
Container
All Known Implementing Classes:
StandardWrapper

public interface Wrapper
extends Container

A Wrapper is a Container that represents an individual servlet definition from the deployment descriptor of the web application. It provides a convenient mechanism to use Interceptors that see every single request to the servlet represented by this definition.

Implementations of Wrapper are responsible for managing the servlet life cycle for their underlying servlet class, including calling init() and destroy() at appropriate times, as well as respecting the existence of the SingleThreadModel declaration on the servlet class itself.

The parent Container attached to a Wrapper will generally be an implementation of Context, representing the servlet context (and therefore the web application) within which this servlet executes.

Child Containers are not allowed on Wrapper implementations, so the addChild() method should throw an IllegalArgumentException.

Version:
$Revision: 1.5 $ $Date: 2001/07/22 20:13:30 $
Author:
Craig R. McClanahan

Field Summary
 
Fields inherited from interface org.apache.catalina.Container
ADD_CHILD_EVENT, ADD_MAPPER_EVENT, ADD_VALVE_EVENT, REMOVE_CHILD_EVENT, REMOVE_MAPPER_EVENT, REMOVE_VALVE_EVENT
 
Method Summary
 void addInitParameter(java.lang.String name, java.lang.String value)
          Add a new servlet initialization parameter for this servlet.
 void addInstanceListener(InstanceListener listener)
          Add a new listener interested in InstanceEvents.
 void addSecurityReference(java.lang.String name, java.lang.String link)
          Add a new security role reference record to the set of records for this servlet.
 javax.servlet.Servlet allocate()
          Allocate an initialized instance of this Servlet that is ready to have its service() method called.
 void deallocate(javax.servlet.Servlet servlet)
          Return this previously allocated servlet to the pool of available instances.
 java.lang.String findInitParameter(java.lang.String name)
          Return the value for the specified initialization parameter name, if any; otherwise return null.
 java.lang.String[] findInitParameters()
          Return the names of all defined initialization parameters for this servlet.
 java.lang.String findSecurityReference(java.lang.String name)
          Return the security role link for the specified security role reference name, if any; otherwise return null.
 java.lang.String[] findSecurityReferences()
          Return the set of security role reference names associated with this servlet, if any; otherwise return a zero-length array.
 long getAvailable()
          Return the available date/time for this servlet, in milliseconds since the epoch.
 java.lang.String getJspFile()
          Return the context-relative URI of the JSP file for this servlet.
 int getLoadOnStartup()
          Return the load-on-startup order value (negative value means load on first call).
 java.lang.String getRunAs()
          Return the run-as identity for this servlet.
 java.lang.String getServletClass()
          Return the fully qualified servlet class name for this servlet.
 boolean isUnavailable()
          Is this servlet currently unavailable?
 void load()
          Load and initialize an instance of this servlet, if there is not already at least one initialized instance.
 void removeInitParameter(java.lang.String name)
          Remove the specified initialization parameter from this servlet.
 void removeInstanceListener(InstanceListener listener)
          Remove a listener no longer interested in InstanceEvents.
 void removeSecurityReference(java.lang.String name)
          Remove any security role reference for the specified role name.
 void setAvailable(long available)
          Set the available date/time for this servlet, in milliseconds since the epoch.
 void setJspFile(java.lang.String jspFile)
          Set the context-relative URI of the JSP file for this servlet.
 void setLoadOnStartup(int value)
          Set the load-on-startup order value (negative value means load on first call).
 void setRunAs(java.lang.String runAs)
          Set the run-as identity for this servlet.
 void setServletClass(java.lang.String servletClass)
          Set the fully qualified servlet class name for this servlet.
 void unavailable(javax.servlet.UnavailableException unavailable)
          Process an UnavailableException, marking this servlet as unavailable for the specified amount of time.
 void unload()
          Unload all initialized instances of this servlet, after calling the destroy() method for each instance.
 
Methods inherited from interface org.apache.catalina.Container
addChild, addContainerListener, addMapper, addPropertyChangeListener, findChild, findChildren, findMapper, findMappers, getCluster, getInfo, getLoader, getLogger, getManager, getName, getParent, getParentClassLoader, getRealm, getResources, invoke, map, removeChild, removeContainerListener, removeMapper, removePropertyChangeListener, setCluster, setLoader, setLogger, setManager, setName, setParent, setParentClassLoader, setRealm, setResources
 

Method Detail

getAvailable

public long getAvailable()
Return the available date/time for this servlet, in milliseconds since the epoch. If this date/time is in the future, any request for this servlet will return an SC_SERVICE_UNAVAILABLE error. If it is zero, the servlet is currently available. A value equal to Long.MAX_VALUE is considered to mean that unavailability is permanent.


setAvailable

public void setAvailable(long available)
Set the available date/time for this servlet, in milliseconds since the epoch. If this date/time is in the future, any request for this servlet will return an SC_SERVICE_UNAVAILABLE error. A value equal to Long.MAX_VALUE is considered to mean that unavailability is permanent.

Parameters:
available - The new available date/time

getJspFile

public java.lang.String getJspFile()
Return the context-relative URI of the JSP file for this servlet.


setJspFile

public void setJspFile(java.lang.String jspFile)
Set the context-relative URI of the JSP file for this servlet.

Parameters:
jspFile - JSP file URI

getLoadOnStartup

public int getLoadOnStartup()
Return the load-on-startup order value (negative value means load on first call).


setLoadOnStartup

public void setLoadOnStartup(int value)
Set the load-on-startup order value (negative value means load on first call).

Parameters:
value - New load-on-startup value

getRunAs

public java.lang.String getRunAs()
Return the run-as identity for this servlet.


setRunAs

public void setRunAs(java.lang.String runAs)
Set the run-as identity for this servlet.


getServletClass

public java.lang.String getServletClass()
Return the fully qualified servlet class name for this servlet.


setServletClass

public void setServletClass(java.lang.String servletClass)
Set the fully qualified servlet class name for this servlet.

Parameters:
servletClass - Servlet class name

isUnavailable

public boolean isUnavailable()
Is this servlet currently unavailable?


addInitParameter

public void addInitParameter(java.lang.String name,
                             java.lang.String value)
Add a new servlet initialization parameter for this servlet.

Parameters:
name - Name of this initialization parameter to add
value - Value of this initialization parameter to add

addInstanceListener

public void addInstanceListener(InstanceListener listener)
Add a new listener interested in InstanceEvents.

Parameters:
listener - The new listener

addSecurityReference

public void addSecurityReference(java.lang.String name,
                                 java.lang.String link)
Add a new security role reference record to the set of records for this servlet.

Parameters:
name - Role name used within this servlet
link - Role name used within the web application

allocate

public javax.servlet.Servlet allocate()
                               throws javax.servlet.ServletException
Allocate an initialized instance of this Servlet that is ready to have its service() method called. If the servlet class does not implement SingleThreadModel, the (only) initialized instance may be returned immediately. If the servlet class implements SingleThreadModel, the Wrapper implementation must ensure that this instance is not allocated again until it is deallocated by a call to deallocate().

Throws:
javax.servlet.ServletException - if the servlet init() method threw an exception
javax.servlet.ServletException - if a loading error occurs

deallocate

public void deallocate(javax.servlet.Servlet servlet)
                throws javax.servlet.ServletException
Return this previously allocated servlet to the pool of available instances. If this servlet class does not implement SingleThreadModel, no action is actually required.

Parameters:
servlet - The servlet to be returned
Throws:
javax.servlet.ServletException - if a deallocation error occurs

findInitParameter

public java.lang.String findInitParameter(java.lang.String name)
Return the value for the specified initialization parameter name, if any; otherwise return null.

Parameters:
name - Name of the requested initialization parameter

findInitParameters

public java.lang.String[] findInitParameters()
Return the names of all defined initialization parameters for this servlet.


findSecurityReference

public java.lang.String findSecurityReference(java.lang.String name)
Return the security role link for the specified security role reference name, if any; otherwise return null.

Parameters:
name - Security role reference used within this servlet

findSecurityReferences

public java.lang.String[] findSecurityReferences()
Return the set of security role reference names associated with this servlet, if any; otherwise return a zero-length array.


load

public void load()
          throws javax.servlet.ServletException
Load and initialize an instance of this servlet, if there is not already at least one initialized instance. This can be used, for example, to load servlets that are marked in the deployment descriptor to be loaded at server startup time.

Throws:
javax.servlet.ServletException - if the servlet init() method threw an exception
javax.servlet.ServletException - if some other loading problem occurs

removeInitParameter

public void removeInitParameter(java.lang.String name)
Remove the specified initialization parameter from this servlet.

Parameters:
name - Name of the initialization parameter to remove

removeInstanceListener

public void removeInstanceListener(InstanceListener listener)
Remove a listener no longer interested in InstanceEvents.

Parameters:
listener - The listener to remove

removeSecurityReference

public void removeSecurityReference(java.lang.String name)
Remove any security role reference for the specified role name.

Parameters:
name - Security role used within this servlet to be removed

unavailable

public void unavailable(javax.servlet.UnavailableException unavailable)
Process an UnavailableException, marking this servlet as unavailable for the specified amount of time.

Parameters:
unavailable - The exception that occurred, or null to mark this servlet as permanently unavailable

unload

public void unload()
            throws javax.servlet.ServletException
Unload all initialized instances of this servlet, after calling the destroy() method for each instance. This can be used, for example, prior to shutting down the entire servlet engine, or prior to reloading all of the classes from the Loader associated with our Loader's repository.

Throws:
javax.servlet.ServletException - if an unload error occurs


Copyright 2000-2001 Apache Software Foundation. All Rights Reserved.