com.google.web.bindery.requestfactory.gwt.client
Class RequestBatcher<F extends RequestFactory,C extends RequestContext>

java.lang.Object
  com.google.web.bindery.requestfactory.gwt.client.RequestBatcher<F,C>

Type Parameters:

F - the type of RequestFactory

C - any RequestContext type

public abstract class RequestBatcher<F extends RequestFactory,C extends RequestContext>
extends java.lang.Object

A RequestBatcher is a convenience class that allows RequestFactory operations to be aggregated over a single tick of the event loop and sent as one HTTP request. Instances of RequestBatcher are reusable, so they may be used as application-wide singleton objects or within a particular subsystem or UI.

Subclasses need only to provide the instance of the RequestFactory used by the application and a method to provide a "default" RequestContext from the RequestFactory.

 public class MyRequestBatcher extends RequestBatcher {
   public MyRequestBatcher() {
     // MyRequestFactory could also be injected
     super(GWT.create(MyRequestFactory.class));
   }
   
   protected MyRequestContext createContext(MyRequestFactory factory) {
     return factory.myRequestContext();
   }
 }
 

When an application uses multiple RequestContext types, the RequestContext.append(RequestContext) method can be used to chain multiple RequestContext objects together:

 class MyRequestBatcher {
   public OtherRequestContext otherContext() {
     return get().append(getFactory().otherContext());
   }
 }
 

See Also:

Scheduler.scheduleFinally(ScheduledCommand)

RequestBatcher

protected RequestBatcher(F requestFactory)

get

public C get()

Returns a mutable RequestContext.

get

public C get(Receiver<java.lang.Void> receiver)

Returns a mutable RequestContext and enqueues the given receiver to be called as though it had been passed directly to RequestContext.fire(Receiver).

getRequestFactory

public F getRequestFactory()

Convenience access to the RequestFactory instance to aid developers using multiple RequestContext types.

 RequestBatcher<MyRequestFactory, MyRequestContext> batcher;
 
 public void useOtherRequestContext() {
   OtherRequestContext ctx = batcher.get().append(batcher.getFactory().otherContext());
   ctx.someOtherMethod().to(someReceiver);
 }
 

createContext

protected abstract C createContext(F requestFactory)

Subclasses must implement this method to return an instance of a RequestContext.

getScheduler

protected Scheduler getScheduler()

Returns Scheduler.get(), but may be overridden for testing purposes.