Mega Code Archive
A NumberedSet is a generic container of Objects where each element is identified by an integer id
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/*
* 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 <aturk@biggeruniverse.com>
* Bjorn Lindeijer <bjorn@lindeijer.nl>
*/
//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.
*
* todo: this function shifts the ids of any subsequent elements!
*
* @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 maxId = data.size() - 1;
while (maxId >= 0) {
if (data.get(maxId) != null) {
break;
}
maxId--;
}
return maxId;
}
/**
* 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() + 1;
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();
}
}
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