org.eclipse.jetty.server.handler
Class ScopedHandler

java.lang.Object
  org.eclipse.jetty.util.component.AbstractLifeCycle
      org.eclipse.jetty.server.handler.AbstractHandler
          org.eclipse.jetty.server.handler.AbstractHandlerContainer
              org.eclipse.jetty.server.handler.HandlerWrapper
                  org.eclipse.jetty.server.handler.ScopedHandler

All Implemented Interfaces:

Handler, HandlerContainer, LifeCycle

Direct Known Subclasses:

ContextHandler

public abstract class ScopedHandler
extends HandlerWrapper

ScopedHandler. A ScopedHandler is a HandlerWrapper where the wrapped handlers each define a scope. When handle(String, Request, HttpServletRequest, HttpServletResponse) is called on the first ScopedHandler in a chain of HandlerWrappers, the doScope(String, Request, HttpServletRequest, HttpServletResponse) method is called on all contained ScopedHandlers, before the doHandle(String, Request, HttpServletRequest, HttpServletResponse) method is called on all contained handlers.

For example if Scoped handlers A, B & C were chained together, then the calling order would be:

 A.handle(...)
   A.doScope(...)
     B.doScope(...)
       C.doScope(...)
         A.doHandle(...)
           B.doHandle(...)
              C.doHandle(...)   
 
 
 
If non scoped handler X was in the chained A, B, X & C, then 
 the calling order would be:
 A.handle(...)
   A.doScope(...)
     B.doScope(...)
       C.doScope(...)
         A.doHandle(...)
           B.doHandle(...)
             X.handle(...)
               C.handle(...)
                 C.doHandle(...)   
 
 
 
A typical usage pattern is:
     private static class MyHandler extends ScopedHandler
     {
         public void doScope(String target, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
         {
             try
             {
                 setUpMyScope();
                 super.doScope(target,request,response);
             }
             finally
             {
                 tearDownMyScope();
             }
         }
         
         public void doHandle(String target, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
         {
             try
             {
                 doMyHandling();
                 super.doHandle(target,request,response);
             }
             finally
             {
                 cleanupMyHandling();
             }
         }
     }
 









Nested Class Summary

 
Nested classes/interfaces inherited from interface org.eclipse.jetty.util.component.LifeCycle
LifeCycle.Listener
 



Field Summary




protected  ScopedHandler
_nextScope



           



protected  ScopedHandler
_outerScope



           


 
Fields inherited from class org.eclipse.jetty.server.handler.HandlerWrapper
_handler
 
Fields inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle
_listeners, FAILED, RUNNING, STARTED, STARTING, STOPPED, STOPPING
 



Constructor Summary
ScopedHandler()



           
 



Method Summary




abstract  void
doHandle(java.lang.String target,
         Request baseRequest,
         javax.servlet.http.HttpServletRequest request,
         javax.servlet.http.HttpServletResponse response)



           



abstract  void
doScope(java.lang.String target,
        Request baseRequest,
        javax.servlet.http.HttpServletRequest request,
        javax.servlet.http.HttpServletResponse response)



           



protected  void
doStart()



           



 void
handle(java.lang.String target,
       Request baseRequest,
       javax.servlet.http.HttpServletRequest request,
       javax.servlet.http.HttpServletResponse response)



          Handle a request.



 void
nextHandle(java.lang.String target,
           Request baseRequest,
           javax.servlet.http.HttpServletRequest request,
           javax.servlet.http.HttpServletResponse response)



           



 void
nextScope(java.lang.String target,
          Request baseRequest,
          javax.servlet.http.HttpServletRequest request,
          javax.servlet.http.HttpServletResponse response)



           


 
Methods inherited from class org.eclipse.jetty.server.handler.HandlerWrapper
doStop, expandChildren, getHandler, getHandlers, setHandler, setServer
 
Methods inherited from class org.eclipse.jetty.server.handler.AbstractHandlerContainer
dump, expandHandler, getChildHandlerByClass, getChildHandlers, getChildHandlersByClass
 
Methods inherited from class org.eclipse.jetty.server.handler.AbstractHandler
destroy, dump, getServer, toString
 
Methods inherited from class org.eclipse.jetty.util.component.AbstractLifeCycle
addLifeCycleListener, getState, isFailed, isRunning, isStarted, isStarting, isStopped, isStopping, removeLifeCycleListener, start, stop
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface org.eclipse.jetty.util.component.LifeCycle
addLifeCycleListener, isFailed, isRunning, isStarted, isStarting, isStopped, isStopping, removeLifeCycleListener, start, stop
 





Field Detail



_outerScope
protected ScopedHandler _outerScope







_nextScope
protected ScopedHandler _nextScope








Constructor Detail



ScopedHandler
public ScopedHandler()






Method Detail



doStart
protected void doStart()
                throws java.lang.Exception


Overrides:
doStart in class HandlerWrapper



Throws:
java.lang.Exception
See Also:
HandlerWrapper.doStart()





handle
public final void handle(java.lang.String target,
                         Request baseRequest,
                         javax.servlet.http.HttpServletRequest request,
                         javax.servlet.http.HttpServletResponse response)
                  throws java.io.IOException,
                         javax.servlet.ServletException

Description copied from interface: Handler
Handle a request.


Specified by:
handle in interface Handler
Overrides:
handle in class HandlerWrapper


Parameters:
target - The target of the request - either a URI or a name.
baseRequest - The original unwrapped request object.
request - The request either as the Request
 object or a wrapper of that request. The HttpConnection.getCurrentConnection() 
 method can be used access the Request object if required.
response - The response as the Response
 object or a wrapper of that request. The HttpConnection.getCurrentConnection() 
 method can be used access the Response object if required.
Throws:
java.io.IOException
javax.servlet.ServletException





doScope
public abstract void doScope(java.lang.String target,
                             Request baseRequest,
                             javax.servlet.http.HttpServletRequest request,
                             javax.servlet.http.HttpServletResponse response)
                      throws java.io.IOException,
                             javax.servlet.ServletException



Throws:
java.io.IOException
javax.servlet.ServletException





nextScope
public final void nextScope(java.lang.String target,
                            Request baseRequest,
                            javax.servlet.http.HttpServletRequest request,
                            javax.servlet.http.HttpServletResponse response)
                     throws java.io.IOException,
                            javax.servlet.ServletException



Throws:
java.io.IOException
javax.servlet.ServletException





doHandle
public abstract void doHandle(java.lang.String target,
                              Request baseRequest,
                              javax.servlet.http.HttpServletRequest request,
                              javax.servlet.http.HttpServletResponse response)
                       throws java.io.IOException,
                              javax.servlet.ServletException



Throws:
java.io.IOException
javax.servlet.ServletException





nextHandle
public final void nextHandle(java.lang.String target,
                             Request baseRequest,
                             javax.servlet.http.HttpServletRequest request,
                             javax.servlet.http.HttpServletResponse response)
                      throws java.io.IOException,
                             javax.servlet.ServletException



Throws:
java.io.IOException
javax.servlet.ServletException