ExecutionChannel.java

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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
 * <p/>
 * http://www.apache.org/licenses/LICENSE-2.0
 * <p/>
 * 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.superbiz.stateless.basic;

import java.util.ArrayList;
import java.util.List;

public class ExecutionChannel {

    private static final ExecutionChannel INSTANCE = new ExecutionChannel();

    private final List<ExecutionObserver> observers = new ArrayList<ExecutionObserver>();

    public static ExecutionChannel getInstance() {
        return INSTANCE;
    }

    public void addObserver(ExecutionObserver observer) {
        this.observers.add(observer);
    }

    public void notifyObservers(Object value) {
        for (ExecutionObserver observer : this.observers) {
            observer.onExecution(value);
        }
    }
}