001/*
002 *                    BioJava development code
003 *
004 * This code may be freely distributed and modified under the
005 * terms of the GNU Lesser General Public Licence.  This should
006 * be distributed with the code.  If you do not have a copy,
007 * see:
008 *
009 *      http://www.gnu.org/copyleft/lesser.html
010 *
011 * Copyright for this code is held jointly by the individual
012 * authors.  These should be listed in @author doc comments.
013 *
014 * For more information on the BioJava project and its aims,
015 * or to join the biojava-l mailing list, visit the home page
016 * at:
017 *
018 *      http://www.biojava.org/
019 *
020 */
021package org.biojava.utils;
022
023import java.io.Serializable;
024import java.util.AbstractList;
025
026/**
027 * @author Matthew Pocock
028 */
029public class SingletonList extends AbstractList implements Serializable {
030  private final Object obj;
031  
032  public SingletonList(Object obj) {
033    this.obj = obj;
034  }
035  
036  public int size() {
037    return 1;
038  }
039  
040  public Object get(int i) throws IndexOutOfBoundsException {
041    if(i == 0) {
042      return obj;
043    } else {
044      throw new IndexOutOfBoundsException("Can't access item " + i + " of 1");
045    }
046  }
047}