pl.touk.tscreload.impl.Observable Maven / Gradle / Ivy

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/*
 * Copyright 2015 the original author or 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.
 */
package pl.touk.tscreload.impl;

import java.util.Collections;
import java.util.Set;
import java.util.WeakHashMap;

public abstract class Observable {

    private final Set> observers = Collections.newSetFromMap(new WeakHashMap<>());

    public void addWeakObserver(Observer observer) {
        synchronized (observers) {
            observers.add(observer);
        }
    }

    protected void notifyObservers(T changedValue) {
        synchronized (observers) {
            observers.forEach(o -> o.notifyChanged(changedValue));
        }
    }

}