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).