org.eclipse.jetty.util

Class BlockingCallback

java.lang.Object

org.eclipse.jetty.util.BlockingCallback

All Implemented Interfaces:

Callback

public class BlockingCallback
extends Object
implements Callback

A Callback for simple reusable conversion of an asynchronous API to blocking.

To avoid late redundant calls to succeeded() or failed(Throwable) from interfering with later reuses of this class, the callback context is used to hold pass a phase indicated and only a single callback per phase is allowed.

A typical usage pattern is:

 public class MyClass
 {
     BlockingCallback cb = new BlockingCallback();
     
     public void blockingMethod(Object args) throws Exception
     {
         asyncMethod(args,cb);
         cb.block();
     }
     
     public void asyncMethod(Object args, Callback callback)
     {
         ...
     }
  }

Nested Class Summary

Nested classes/interfaces inherited from interface org.eclipse.jetty.util.Callback

Callback.Adapter

Constructor Summary

Constructors

Constructor and Description
BlockingCallback()

Method Summary

Methods

Modifier and Type	Method and Description
void	block() Block until the Callback has succeeded or failed and after the return leave in the state to allow reuse.
void	failed(Throwable cause) Callback invoked when the operation fails.
void	succeeded() Callback invoked when the operation completes.
String	toString()

Methods inherited from class java.lang.Object

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

Constructor Detail

BlockingCallback

public BlockingCallback()

Method Detail

succeeded

public void succeeded()

Description copied from interface: Callback

Callback invoked when the operation completes.

Specified by:

succeeded in interface Callback

See Also:

Callback.failed(Throwable)

failed

public void failed(Throwable cause)

Description copied from interface: Callback

Callback invoked when the operation fails.

Specified by:

failed in interface Callback

Parameters:

cause - the reason for the operation failure

block

public void block()
           throws IOException

Block until the Callback has succeeded or failed and after the return leave in the state to allow reuse. This is useful for code that wants to repeatable use a FutureCallback to convert an asynchronous API to a blocking API.

Throws:

IOException - if exception was caught during blocking, or callback was cancelled

toString

public String toString()

Overrides:

toString in class Object