com.google.common.collect.AbstractIndexedIterator Maven / Gradle / Ivy
/*
* Copyright (C) 2009 Google 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.google.common.collect;
import com.google.common.annotations.GwtCompatible;
import java.util.NoSuchElementException;
/**
* This class provides a skeletal implementation of an iterator across a fixed
* number of elements that may be retrieved by position.
*
* @author Jared Levy
*/
@GwtCompatible
abstract class AbstractIndexedIterator extends UnmodifiableIterator {
// TODO: Make public? If public, constructor should verify that size >= 0.
private final int size;
private int position;
/**
* Returns the element with the specified index. This method is called by
* {@link #next()}.
*/
protected abstract E get(int index);
// TODO: Add constructor taking an offset.
protected AbstractIndexedIterator(int size) {
this.size = size;
}
public final boolean hasNext() {
return position < size;
}
public final E next() {
if (!hasNext()) {
throw new NoSuchElementException();
}
return get(position++);
}
}