Var.java

/**
 * Copyright 2008 - 2015 The Loon Game Engine Authors
 * 
 * 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.
 * 
 * @project loon
 * @author cping
 * @email：javachenpeng@yahoo.com
 * @version 0.5
 */
package loon.utils.reply;

public class Var<T> extends AbstractValue<T>
{

    public static <T> Var<T> create (T value) {
        return new Var<T>(value);
    }

    public Var (T value) {
        _value = value;
    }

    public T update (T value) {
        return updateAndNotifyIf(value);
    }

    public T updateForce (T value) {
        return updateAndNotify(value);
    }

    public Port<T> port () {
        return new Port<T> () {
            @Override public void onEmit (T value) {
                update(value);
            }
        };
    }

    @Override public T get () {
        return _value;
    }

    @Override protected T updateLocal (T value) {
        T oldValue = _value;
        _value = value;
        return oldValue;
    }

    protected T _value;
}