indexedunorderset.java

JAVA3D矩陈的相关类

/*
 * $RCSfile: IndexedUnorderSet.java,v $
 *
 * Copyright (c) 2007 Sun Microsystems, Inc. All rights reserved.
 *
 * Use is subject to license terms.
 *
 * $Revision: 1.6 $
 * $Date: 2007/04/12 17:34:05 $
 * $State: Exp $
 */

package javax.media.j3d;

/**
 * A strongly type indexed unorder set.
 * All operations remove(IndexedObject, ListType), add(IndexedObject, ListType),
 * contains(IndexedObject, ListType) etc. take O(1) time.
 * The class is designed to optimize speed. So many reductance
 * procedures call and range check as found in ArrayList are 
 * removed.
 *
 * <p>
 * Use the following code to iterate through an array.
 *
 * <pre>
 *  IndexedUnorderSet  IUset =
 *      new IndexedUnorderSet(YourClass.class, listType);
 *  // add element here
 *
 *  YourClass[] arr = (YourClass []) IUset.toArray();
 *  int size = IUset.arraySize();
 *  for (int i=0; i < size; i++) {
 *      YourClass obj = arr[i];
 *      ....
 *  }
 * </pre>
 *
 * <p>
 * Note:
 * <ul>
 * 1) The array return is a copied of internal array.<br>
 * 2) Don't use arr.length , use IUset.arraySize();<br>
 * 3) IndexedObject contains an array of listIndex, the number of
 * array elements depends on the number of different types of 
 * IndexedUnorderSet that use it.<br>
 * 4) No need to do casting for individual element as in ArrayList.<br>
 * 5) IndexedUnorderSet is thread safe.<br>
 * 6) Object implement this interface MUST initialize the index to -1.<br>
 * </ul>
 *
 * <p>
 * Limitation:
 * <ul>
 *       1) Order of IndexedObject in list is not important<br>
 *       2) Can't modify the clone() copy.<br>
 *       3) IndexedObject can't be null<br>
 * </ul>
 */

class IndexedUnorderSet implements Cloneable, java.io.Serializable  {

    // XXXX: set to false when release
    final static boolean debug = false;

    /**
     * The array buffer into which the elements of the ArrayList are stored.
     * The capacity of the ArrayList is the length of this array buffer.
     *
     * It is non-private to enable compiler do inlining for get(),
     * set(), remove() when -O flag turn on.
     */
    transient IndexedObject elementData[];

    /**
     * Clone copy of elementData return by toArray(true);
     */
    transient Object cloneData[];
    // size of the above clone objec.
    transient int cloneSize;

    transient boolean isDirty = true;

    /**
     * Component Type of individual array element entry
     */
     Class componentType;

    /**
     * The size of the ArrayList (the number of elements it contains).
     *
     * We make it non-private to enable compiler do inlining for
     * getSize() when -O flag turn on.
     */
    int size;

    int listType;

    // Current VirtualUniverse using this structure
    VirtualUniverse univ;

    /**
     * Constructs an empty list with the specified initial capacity.
     * and the class data Type
     *
     * @param   initialCapacity   the initial capacity of the list.
     * @param   componentType     class type of element in the list.
     */
     IndexedUnorderSet(int initialCapacity, Class componentType,
		       int listType, VirtualUniverse univ) {
	this.componentType = componentType;
	this.elementData = (IndexedObject[])java.lang.reflect.Array.newInstance(
						componentType, initialCapacity);
	this.listType = listType;
	this.univ = univ;
    }

    /**
     * Constructs an empty list.
     * @param   componentType     class type of element in the list.
     */
     IndexedUnorderSet(Class componentType, int listType,
		       VirtualUniverse univ) {
	this(10, componentType, listType, univ);
     }


    /**
     * Constructs an empty list with the specified initial capacity.
     *
     * @param   initialCapacity   the initial capacity of the list.
     */
     IndexedUnorderSet(int initialCapacity, int listType,
		       VirtualUniverse univ) {
	 this(initialCapacity, IndexedObject.class, listType, univ);
     }

    /**
     * Constructs an empty list.
     * @param listType default to Object.
     */
     IndexedUnorderSet(int listType, VirtualUniverse univ) {
	this(10, IndexedObject.class, listType, univ);
    }

    /**
     * Initialize all indexes to -1
     */
    final static void init(IndexedObject obj, int len) {
	obj.listIdx = new int[3][];

	obj.listIdx[0] = new int[len];
	obj.listIdx[1] = new int[len];
	obj.listIdx[2] = new int[1];

	for (int i=0; i < len; i++) {
	    obj.listIdx[0][i] = -1;
	    obj.listIdx[1][i] = -1;
	}
	
	// Just want to set both RenderMolecule idx
	// and BehaviorRetained idx to 0 by default
	// It is OK without the following lines
	if (obj instanceof SceneGraphObjectRetained) {
	    // setlive() will change this back to 0
	    obj.listIdx[2][0] = 1;
	} else {
	    obj.listIdx[2][0] = 0;
	}
    }

    /**
     * Returns the number of elements in this list.
     *
     * @return  the number of elements in this list.
     */
    final int size() {
	return size;
    }

  
    /**
     * Returns the size of entry use in toArray() number of elements 
     * in this list.
     *
     * @return  the number of elements in this list.
     */
    final int arraySize() {
	return cloneSize;
    }

    /**
     * Tests if this list has no elements.
     *
     * @return  <tt>true</tt> if this list has no elements;
     *          <tt>false</tt> otherwise.
     */
    final boolean isEmpty() {
	return size == 0;
    }

    /**
     * Returns <tt>true</tt> if this list contains the specified element.
     *
     * @param o element whose presence in this List is to be tested.
     */
    synchronized final boolean contains(IndexedObject o) {
	return (o.listIdx[o.getIdxUsed(univ)][listType] >= 0);
    }


    /**
     * Searches for the last occurence of the given argument, testing 
     * for equality using the <tt>equals</tt> method. 
     *
     * @param   o   an object.
     * @return  the index of the first occurrence of the argument in this
     *          list; returns <tt>-1</tt> if the object is not found.
     * @see     Object#equals(Object)
     */
    synchronized final int indexOf(IndexedObject o) {
	return o.listIdx[o.getIdxUsed(univ)][listType];
    }

    /**
     * Returns a shallow copy of this <tt>ArrayList</tt> instance.  (The
     * elements themselves are not copied.)
     *
     * @return  a clone of this <tt>ArrayList</tt> instance.
     */
    synchronized protected final Object clone() {
	try { 
	    IndexedUnorderSet v = (IndexedUnorderSet)super.clone();
	    v.elementData =  (IndexedObject[])java.lang.reflect.Array.newInstance(
						   componentType, size);
	    System.arraycopy(elementData, 0, v.elementData, 0, size);
	    isDirty = true; // can't use the old cloneData reference
	    return v;
	} catch (CloneNotSupportedException e) { 
	    // this shouldn't happen, since we are Cloneable
	    throw new InternalError();
	}
    }


    /**
     * Returns an array containing all of the elements in this list.
     * The size of the array may longer than the actual size. Use
     * arraySize() to retrieve the size. 
     * The array return is a copied of internal array. if copy
     * is true.
     *
     * @return an array containing all of the elements in this list
     */
    synchronized final Object[] toArray(boolean copy) {
	if (copy) {
	    if (isDirty) {
		if ((cloneData == null) || cloneData.length < size) {
		    cloneData = (Object[])java.lang.reflect.Array.newInstance(
									      componentType, size);
		}
		System.arraycopy(elementData, 0, cloneData, 0, size);
		cloneSize = size;
		isDirty = false;
	    }
	    return cloneData;
	} else {
	    cloneSize = size;
	    return elementData;
	}
 
    }

    /**
     * Returns an array containing all of the elements in this list.
     * The size of the array may longer than the actual size. Use
     * arraySize() to retrieve the size. 
     * The array return is a copied of internal array. So another
     * thread can continue add/delete the current list. However,
     * it should be noticed that two call to toArray() may return
     * the same copy.
     *
     * @return an array containing all of the elements in this list
     */
    synchronized final Object[] toArray() {
	return toArray(true);
    }


    /**
     * Returns an array containing elements starting from startElement
     * all of the elements in this list. A new array of exact size 
     * is always allocated.
     *
     * @param startElement starting element to copy 
     *
     * @return an array containing elements starting from
     *         startElement, null if element not found.
     *
     */