numberedset.java

tiled地图编辑器是2d的,很不错的国外软件,使用起来很方便的

/*
 *  Tiled Map Editor, (c) 2004-2006
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  Adam Turk <[e-mail]>
 *  Bjorn Lindeijer <[e-mail]>
 */

package tiled.util;

import java.util.Iterator;
import java.util.Vector;

/**
 * A NumberedSet is a generic container of Objects where each element is
 * identified by an integer id.  Unlike with a Vector, the mapping between
 * id and element remains unaffected when elements are deleted.  This means
 * that the set of ids for a NumberedSet may not be contiguous. (A sparse
 * array)
 *
 * @author rainerd
 */
public class NumberedSet
{
	private Vector data;

	/**
	 * Constructs a new empty NumberedSet.
	 */
	public NumberedSet() {
		data = new Vector();
	}

	/**
	 * Returns the element for a specific element, or null if the id does not
	 * identify any element in this NumberedSet.
	 *
	 * @param id
	 * @return Object
	 */
	public Object get(int id) {
		try {
			return data.get(id);
		} catch (ArrayIndexOutOfBoundsException e) {}

		return null;
	}

	/**
	 * Returns true if the NumberedSet contains an element for the specified id.
	 *
	 * @param id
	 * @return boolean
	 */
	public boolean containsId(int id) {
		return get(id) != null;
	}

	/**
	 * Sets the element for the specified id, replacing any previous element that
	 * was associated with that id.  id should be a relatively small positive
	 * integer.
	 *
	 * @param id
	 * @param o
	 * @return int
	 * @throws IllegalArgumentException
	 */
	public int put(int id, Object o) throws IllegalArgumentException {
		if (id < 0) throw new IllegalArgumentException();

		// Make sure there is sufficient space to overlay
		for (int i = id - data.size(); i > 0; i--) {
            data.add(null);
        }

		data.add(id, o);
		return id;
	}

	/**
	 * Removes the element associated with the given id from the NumberedSet.
	 *
	 * @param id
	 */
	public void remove(int id) {
		data.remove(id);
	}

	/**
	 * Returns the last id in the NumberedSet that is associated with an element,
	 * or -1 if the NumberedSet is empty.
	 *
	 * @return int
	 */
	public int getMaxId() {
		int id = -1;
		for (int i = 0; i < data.size(); i++) {
			if (data.get(i) != null) id = i;
		}

		return id + 1;
	}

	/**
	 * Returns an iterator to iterate over the elements of the NumberedSet.
	 *
	 * @return NumberedSetIterator
	 */
	public Iterator iterator() {
		return data.iterator();
	}

	/**
	 * Adds a new element to the NumberedSet and returns its id.
	 *
	 * @param o
	 * @return int
	 */
	public int add(Object o) {
	  int id = getMaxId();
	  put(id, o);
	  return id;
	}

	/**
	 * Returns the id of the first element of the NumberedSet that is euqal to
	 * the given object, or -1 otherwise.
	 *
	 * @param o
	 */
	public int indexOf(Object o) {
		return data.indexOf(o);
	}

	/**
	 * Returns true if at least one element of the NumberedSet is equal to the
	 * given object.
	 */
	public boolean contains(Object o) {
		return data.contains(o);
	}

	/**
	 * If this NumberedSet already contains an element equal to the given object,
	 * return its id.  Otherwise insert the given object into the NumberedSet
	 * and return its id.
	 */
	public int findOrAdd(Object o) {
		int id = indexOf(o);
		if (id != -1) return id;
		return add(o);
	}

	/**
	 * Returns the number of actual elements in the NumberedSet.
	 *
	 * @return int
	 */
  	public int size() {
  		return data.size();
  	}
}