/*
* 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.internal.collection;
import static java.util.Objects.requireNonNull;
import java.util.ListIterator;
import java.util.NoSuchElementException;
/**
* @author <a href="mailto:franz.wilhelmstoetter@gmx.at">Franz Wilhelmstötter</a>
* @since 1.4
* @version 3.4
*/
public class ArrayIterator<T> implements ListIterator<T> {
public final Array<T> array;
protected int cursor = 0;
protected int lastElement = -1;
public ArrayIterator(final Array<T> array) {
this.array = requireNonNull(array, "Array must not be null.");
}
@Override
public boolean hasNext() {
return cursor != array.length();
}
@Override
public T next() {
final int i = cursor;
if (cursor >= array.length()) {
throw new NoSuchElementException();
}
cursor = i + 1;
return array.get(lastElement = i);
}
@Override
public int nextIndex() {
return cursor;
}
@Override
public boolean hasPrevious() {
return cursor != 0;
}
@Override
public T previous() {
final int i = cursor - 1;
if (i < 0) {
throw new NoSuchElementException();
}
cursor = i;
return array.get(lastElement = i);
}
@Override
public int previousIndex() {
return cursor - 1;
}
@Override
public void set(final T value) {
throw new UnsupportedOperationException(
"Iterator is immutable."
);
}
@Override
public void add(final T value) {
throw new UnsupportedOperationException(
"Can't change Iterator size."
);
}
@Override
public void remove() {
throw new UnsupportedOperationException(
"Can't change Iterator size."
);
}
}