/*
* Copyright 2013 Google Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not
* use this file except in compliance with the License. You may obtain a copy of
* the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations under
* the License.
*/
package com.google.web.bindery.event.shared.binder.impl;
import com.google.web.bindery.event.shared.EventBus;
import com.google.web.bindery.event.shared.HandlerRegistration;
import com.google.web.bindery.event.shared.binder.EventBinder;
import com.google.web.bindery.event.shared.binder.GenericEvent;
import java.util.List;
/**
* Base class containing code shared by all generated {@link EventBinder}s.
* Users shouldn't need to reference this class directly.
*
* @param <T> type of object being bound
* @author ekuefler@google.com (Erik Kuefler)
*/
public abstract class AbstractEventBinder<T> implements EventBinder<T> {
@Override
public final HandlerRegistration bindEventHandlers(T target, EventBus eventBus) {
final List<HandlerRegistration> registrations = doBindEventHandlers(target, eventBus);
return new HandlerRegistration() {
@Override
public void removeHandler() {
for (HandlerRegistration registration : registrations) {
registration.removeHandler();
}
registrations.clear();
}
};
}
/**
* Implemented by EventBinderGenerator to do the actual work of binding event handlers on the
* target.
*/
protected abstract List<HandlerRegistration> doBindEventHandlers(T target, EventBus eventBus);
/**
* Registers the given handler for the given event class on the given event bus. Factored out
* into a method here instead of generated directly in order to simplify the generated code and
* save a little space.
*/
protected final <U extends GenericEvent> void bind(
EventBus eventBus,
List<HandlerRegistration> registrations,
Class<U> type,
GenericEventHandler handler) {
registrations.add(eventBus.addHandler(GenericEventType.getTypeOf(type), handler));
}
}