/*
* Copyright (C) 2012 Red Hat, Inc. and/or its affiliates.
*
* 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 org.jboss.errai.bus.server.service;
import java.util.Collections;
import java.util.HashSet;
import java.util.Set;
/**
* @author Mike Brock
*/
public final class ErraiServiceSingleton {
private ErraiServiceSingleton() {
}
private static Set<ErraiInitCallback> callbackList = Collections.synchronizedSet(new HashSet<ErraiInitCallback>());
private static final Object monitor = new Object();
private static volatile ErraiService service = new ErraiServiceProxy();
public static ErraiService initSingleton(final ErraiServiceConfigurator configurator) {
synchronized (monitor) {
if (isInitialized()) throw new IllegalStateException("service already set into singleton");
ErraiServiceProxy proxy = (ErraiServiceProxy) service;
service = ErraiServiceFactory.create(configurator);
proxy.closeProxy(service);
for (ErraiInitCallback erraiInitCallback : callbackList) {
erraiInitCallback.onInit(service);
}
return service;
}
}
public static boolean isInitialized() {
return !(service instanceof ErraiServiceProxy);
}
public static ErraiService getService() {
return service;
}
public static void registerInitCallback(ErraiInitCallback callback) {
synchronized (monitor) {
if (isInitialized()) {
callback.onInit(getService());
}
callbackList.add(callback);
}
}
public static Set<ErraiInitCallback> getInitCallbacks() {
return Collections.unmodifiableSet(callbackList);
}
public static interface ErraiInitCallback {
public void onInit(ErraiService service);
}
}