net.sf.staccatocommons.collections.internal.iterator.TakeIterator Maven / Gradle / Ivy

/*
 Copyright (c) 2011, The Staccato-Commons Team

 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU Lesser General Public License as published by
 the Free Software Foundation; version 3 of the License.

 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 GNU Lesser General Public License for more details.
 */
package net.sf.staccatocommons.collections.internal.iterator;

import java.util.NoSuchElementException;

import net.sf.staccatocommons.defs.Thunk;
import net.sf.staccatocommons.iterators.thriter.AdvanceThriterator;
import net.sf.staccatocommons.iterators.thriter.Thriter;
import net.sf.staccatocommons.restrictions.check.NonNull;

/**
 * @author flbulgarelli
 * 
 */
public class TakeIterator extends AdvanceThriterator {

  private int remaining;
  private final Thriter thriter;

  /**
   * Creates a new {@link TakeIterator} that takes up to {@code n} elements from
   * the given {@code thritter}
   */
  public TakeIterator(int n, @NonNull Thriter thriter) {
    this.thriter = thriter;
    this.remaining = n;
  }

  public boolean hasNext() {
    return remaining > 0 && thriter.hasNext();
  }

  public void advanceNext() throws NoSuchElementException {
    if (!hasNext())
      throw new NoSuchElementException();
    thriter.advanceNext();
    remaining--;
  }

  public A current() throws NoSuchElementException {
    return thriter.current();
  }

  public Thunk delayedCurrent() {
    return thriter.delayedCurrent();
  }

}