org.nnsoft.guice.gguava.eventbus.EventBusModule.java Source code

Introduction

Here is the source code for org.nnsoft.guice.gguava.eventbus.EventBusModule.java

Source

package org.nnsoft.guice.gguava.eventbus;

/*
 *    Copyright 2012 The 99 Software Foundation
 *
 *    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.
 */

import static com.google.common.base.Preconditions.checkArgument;
import static com.google.inject.matcher.Matchers.any;

import static com.google.inject.name.Names.named;

import com.google.common.eventbus.EventBus;
import com.google.inject.AbstractModule;
import com.google.inject.TypeLiteral;
import com.google.inject.matcher.Matcher;
import com.google.inject.spi.InjectionListener;
import com.google.inject.spi.TypeEncounter;
import com.google.inject.spi.TypeListener;

/**
 * This class was originally developed by <a href="http://spin.atomicobject.com/author/dewind/">Justin DeWind</a>
 * on <a href="http://spin.atomicobject.com/2012/01/13/the-guava-eventbus-on-guice/">Atomicobject</a> blog, under the
 * terms of the MIT License.
 */
public abstract class EventBusModule extends AbstractModule {

    protected BusMatcher bindBus(final String identifier) {
        checkArgument(identifier != null, "Event bus identifier must be not null");

        return new BusMatcher() {

            public void toAnyBoundClass() {
                to(any());
            }

            public void to(Matcher<Object> matcher) {
                checkArgument(matcher != null, "Event bus matcher must be not null");

                final EventBus eventBus = new EventBus(identifier);

                bind(EventBus.class).annotatedWith(named(identifier)).toInstance(eventBus);

                bindListener(matcher, new TypeListener() {
                    public <I> void hear(TypeLiteral<I> typeLiteral, TypeEncounter<I> typeEncounter) {
                        typeEncounter.register(new InjectionListener<I>() {
                            public void afterInjection(I injectee) {
                                eventBus.register(injectee);
                            }
                        });
                    }
                });
            }

        };
    }

}