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The private implementation classes of the Apache MyFaces Core JSF-2.3-next Implementation
/*
* 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
*
* 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.apache.myfaces.util.lang;
import java.util.function.Supplier;
/**
* Inspired by commons-lang LazyInitializer.
*
* @param The type to be lazy initialized.
*/
public class Lazy
{
private static final Object NOT_INITIALIZED = new Object();
@SuppressWarnings("unchecked")
private volatile T value = (T) NOT_INITIALIZED;
private volatile Supplier init;
public Lazy(Supplier init)
{
this.init = init;
}
public synchronized void reset(Supplier init)
{
this.init = init;
this.value = (T) NOT_INITIALIZED;
}
public synchronized void reset(T value)
{
this.value = value;
}
public T get()
{
T result = value;
if (result == NOT_INITIALIZED)
{
synchronized (this)
{
result = value;
if (result == NOT_INITIALIZED)
{
value = init.get();
result = value;
}
}
}
return result;
}
public boolean isInitialized()
{
return value != NOT_INITIALIZED;
}
}