/*******************************************************************************
* Copyright 2014 Analog Devices, Inc.
*
* 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 com.analog.lyric.collect;
import java.util.concurrent.atomic.AtomicReference;
import net.jcip.annotations.NotThreadSafe;
import org.eclipse.jdt.annotation.Nullable;
/**
* {@link ReleasableIterator} that visits all of the elements of an array.
*
* @since 0.05
*/
@NotThreadSafe
public final class ReleasableArrayIterator<T> extends UnmodifiableReleasableIterator<T>
{
private @Nullable T[] _array;
private int _size;
private int _index;
/*---------------
* Construction
*/
private static final AtomicReference<ReleasableArrayIterator<?>> _reusableInstance =
new AtomicReference<ReleasableArrayIterator<?>>();
/**
* Allocates a new instance for given {@code array}.
* <p>
* This method is thread safe.
*/
static public <T2> ReleasableArrayIterator<T2> create(T2[] array)
{
@SuppressWarnings("unchecked")
ReleasableArrayIterator<T2> iter = (ReleasableArrayIterator<T2>) _reusableInstance.getAndSet(null);
if (iter == null)
{
iter = new ReleasableArrayIterator<T2>();
}
iter.reset(array);
return iter;
}
/*------------------
* Iterator methods
*/
@Override
public boolean hasNext()
{
return _index < _size;
}
@SuppressWarnings("null")
@Override
public T next()
{
return _array[_index++];
}
/*----------------------------
* ReleasableIterator methods
*/
@Override
public void release()
{
_array = null;
_reusableInstance.lazySet(this);
}
void reset(T[] array)
{
_array = array;
_size = array.length;
_index = 0;
}
}