/*******************************************************************************
* 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.NoSuchElementException;
import java.util.concurrent.atomic.AtomicInteger;
import net.jcip.annotations.ThreadSafe;
/**
* Partial implementation of {@link PrimitiveIterator} based on an
* array of the primitive type.
*/
@ThreadSafe
public abstract class AbstractPrimitiveArrayIterator<T> implements PrimitiveIterator<T>
{
/*-------
* State
*/
/**
* The one more than the index of the last element in the underlying
* array to be included in the iteration.
*/
protected final int _end;
/**
* The array index of the next element to be returned by the iterator.
*/
private final AtomicInteger _index;
/*--------------
* Construction
*/
/**
* @param start is the index of the first element in the array to
* be included in the iteration.
* @param end is one past the index of the last element in the array
* to be included in the iteration.
*/
protected AbstractPrimitiveArrayIterator(int start, int end)
{
assert(start >= 0);
assert(start <= end);
_end = end;
_index = new AtomicInteger(start);
}
/*------------------
* Iterator methods
*/
@Override
public boolean hasNext()
{
return _index.get() < _end;
}
/**
* @throws UnsupportedOperationException
*/
@Override
public void remove()
{
throw new UnsupportedOperationException("PrimitiveIterator.remove");
}
/*----------------------------------------
* AbstractPrimitiveArrayIterator methods
*/
/**
* @return array index of the next element to be returned by the iteration.
*/
protected int nextIndex()
{
int i = _index.getAndIncrement();
if (i >= _end)
{
throw new NoSuchElementException();
}
return i;
}
}