How to make a server call with out dispatch async instance in gwt

I am using using GWT2.3 with GWTP. Now in this application I need to make a server side call from a non presenter class (So there id no dispatch async instance). Here is my class

public class NameTokenHandler implements ValueChangeHandler<String> {
    @Inject
    DispatchAsync dispatchAsync;
    @Override
    public void onValueChange(ValueChangeEvent<String> event) 开发者_JAVA技巧{
        if (event != null) {
            String nameToken = event.getValue();

            if(dispatchAsync!=null)
            {
                System.out.println("yes");
            } else {
                System.out.println("No");
            }

            History.newItem(nameToken);
        }
    }
}

Here dispatchAsync is always null. I am getting from where it should be initialized so that I can make a server side call. If there is any other way then please let me know. Thanks in advance.

You need to inject the NameTokenHandler, so your dispatcher will be injected too.

public class C {

  private NameTokenHandler handler;

  @Inject
  public C(NameTokenHandler handler) {
    this.handler = handler;
  }

}

This way the handler will be injected to the C class, and your dispatcher will also be injected in the NameTokenHandler. BTW you might need to have a constructor in NameTokenHandler that follows the same pattern (DispatchAsync as a parameter).