Module com.sun.xml.ws

Package com.sun.xml.ws.api.pipe

Interface FiberContextSwitchInterceptor

public interface FiberContextSwitchInterceptor

Interception for Fiber context switch.

Even though pipeline runs asynchronously, sometimes it's desirable to bind some state to the current thread running a fiber. Such state may include security subject (in terms of AccessController.doPrivileged(java.security.PrivilegedAction<T>)), or a transaction.

This mechanism makes it possible to do such things, by allowing some code to be executed before and after a thread executes a fiber.

The design also encapsulates the entire fiber execution in a single opaque method invocation FiberContextSwitchInterceptor.Work.execute(P), allowing the use of finally block.

Author:

Kohsuke Kawaguchi

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static interface	FiberContextSwitchInterceptor.Work<R,P>	Abstraction of the execution that happens inside the interceptor.

Method Summary

Modifier and Type	Method	Description
<R, P> R	execute(Fiber f, P p, FiberContextSwitchInterceptor.Work<R,P> work)	Allows the interception of the fiber execution.

Method Details

execute

<R,
P> R execute(Fiber f,
 P p,
 FiberContextSwitchInterceptor.Work<R,P> work)

Allows the interception of the fiber execution.

This method needs to be implemented like this:

 <R,P> R execute( Fiber f, P p, Work<R,P> work ) {
   // do some preparation work
   ...
   try {
     // invoke
     return work.execute(p);
   } finally {
     // do some clean up work
     ...
   }
 }
 

While somewhat unintuitive, this interception mechanism enables the interceptor to wrap the whole fiber execution into a AccessController.doPrivileged(PrivilegedAction), for example.

Parameters:

f - Fiber to be executed.

p - The opaque parameter value for FiberContextSwitchInterceptor.Work. Simply pass this value to FiberContextSwitchInterceptor.Work.execute(Object).

Returns:

The opaque return value from the the FiberContextSwitchInterceptor.Work. Simply return the value from FiberContextSwitchInterceptor.Work.execute(Object).