SubRangeIterator.java

/*
 * Copyright (c) 2013, SRI International
 * All rights reserved.
 * Licensed under the The BSD 3-Clause License;
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 * 
 * http://opensource.org/licenses/BSD-3-Clause
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 * documentation and/or other materials provided with the distribution.
 * 
 * Neither the name of the aic-util nor the names of its
 * contributors may be used to endorse or promote products derived from
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package com.sri.ai.util.collect;

import java.util.Iterator;

import com.google.common.annotations.Beta;

/**
 * An iterator over a sub-range of a base iterator, from the <code>first</code>
 * -th to the <code>(last-1)</code>-th element.
 * 
 * @author braz
 */
@Beta
public class SubRangeIterator<T> extends FilterIterator<T> {

	int first;
	int last;
	int current;

	public SubRangeIterator(Iterator<T> base, int first, int last) {
		super(base);
		this.first = first;
		this.last = last;
		this.current = 0;
	}

	@Override
	public boolean include(T element) {
		boolean result = current >= first && current < last;
		current++;
		return result;
	}
}