ArraySeqIterator.java
/*
* Java Genetic Algorithm Library (@__identifier__@).
* Copyright (c) @__year__@ Franz Wilhelmstötter
*
* 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.
*
* Author:
* Franz Wilhelmstötter (franz.wilhelmstoetter@gmx.at)
*/
package org.jenetics.util;
import java.util.ListIterator;
import java.util.NoSuchElementException;
/**
* Helper class which iterates over an given array.
*
* @author <a href="mailto:franz.wilhelmstoetter@gmx.at">Franz Wilhelmstötter</a>
* @since 1.0
* @version 1.0 — <em>$Date: 2013-09-18 $</em>
*/
class ArraySeqIterator<T> implements ListIterator<T> {
final ArraySeq<T> _array;
int _cursor;
int _lastElement = -1;
public ArraySeqIterator(final ArraySeq<T> array) {
_array = array;
_cursor = array._start;
}
@Override
public boolean hasNext() {
return _cursor != _array._end;
}
@Override
@SuppressWarnings("unchecked")
public T next() {
final int i = _cursor;
if (_cursor >= _array._end) {
throw new NoSuchElementException();
}
_cursor = i + 1;
return (T)_array._array.data[_lastElement = i];
}
@Override
public int nextIndex() {
return _cursor;
}
@Override
public boolean hasPrevious() {
return _cursor != _array._start;
}
@SuppressWarnings("unchecked")
@Override
public T previous() {
final int i = _cursor - 1;
if (i < _array._start) {
throw new NoSuchElementException();
}
_cursor = i;
return (T)_array._array.data[_lastElement = i];
}
@Override
public int previousIndex() {
return _cursor - 1;
}
@Override
public void set(final T value) {
throw new UnsupportedOperationException("Array is immutable.");
}
@Override
public void add(final T o) {
throw new UnsupportedOperationException("Can't change array size.");
}
@Override
public void remove() {
throw new UnsupportedOperationException("Can't change array size.");
}
}