nboyd%atg.com 9876f36d0e Fix more warnings, serialVersionUID, generics, clean up examples
git-svn-id: svn://10.0.0.236/trunk@251163 18797224-902f-48f8-a5cc-f745e15eee43
2008-05-04 15:22:28 +00:00

281 lines
8.0 KiB
Java

/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* ***** BEGIN LICENSE BLOCK *****
* Version: MPL 1.1/GPL 2.0
*
* The contents of this file are subject to the Mozilla Public License Version
* 1.1 (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS IS" basis,
* WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
* for the specific language governing rights and limitations under the
* License.
*
* The Original Code is Rhino code, released
* May 6, 1998.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corporation.
* Portions created by the Initial Developer are Copyright (C) 1997-1999
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
*
* Alternatively, the contents of this file may be used under the terms of
* the GNU General Public License Version 2 or later (the "GPL"), in which
* case the provisions of the GPL are applicable instead of those above. If
* you wish to allow use of your version of this file only under the terms of
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* them with the notice and other provisions required by the GPL. If you do
* not delete the provisions above, a recipient may use your version of this
* file under either the MPL or the GPL.
*
* ***** END LICENSE BLOCK ***** */
import org.mozilla.javascript.*;
import java.util.List;
import java.util.ArrayList;
/**
* Matrix: An example host object class that implements the Scriptable interface.
*
* Built-in JavaScript arrays don't handle multiple dimensions gracefully: the
* script writer must create every array in an array of arrays. The Matrix class
* takes care of that by automatically allocating arrays for every index that
* is accessed. What's more, the Matrix constructor takes a integer argument
* that specifies the dimension of the Matrix. If m is a Matrix with dimension 3,
* then m[0] will be a Matrix with dimension 1, and m[0][0] will be an Array.
*
* Here's a shell session showing the Matrix object in action:
* <pre>
* js> defineClass("Matrix")
* js> var m = new Matrix(2); // A constructor call, see "Matrix(int dimension)"
* js> m // Object.toString will call "Matrix.getClassName()"
* [object Matrix]
* js> m[0][0] = 3;
* 3
* js> uneval(m[0]); // an array was created automatically!
* [3]
* js> uneval(m[1]); // array is created even if we don't set a value
* []
* js> m.dim; // we can access the "dim" property
* 2
* js> m.dim = 3;
* 3
* js> m.dim; // but not modify the "dim" property
* 2
* </pre>
*
* @see org.mozilla.javascript.Context
* @see org.mozilla.javascript.Scriptable
*
* @author Norris Boyd
*/
public class Matrix implements Scriptable {
/**
* The zero-parameter constructor.
*
* When ScriptableObject.defineClass is called with this class, it will
* construct Matrix.prototype using this constructor.
*/
public Matrix() {
}
/**
* The Java constructor, also used to define the JavaScript constructor.
*/
public Matrix(int dimension) {
if (dimension <= 0) {
throw Context.reportRuntimeError(
"Dimension of Matrix must be greater than zero");
}
dim = dimension;
list = new ArrayList<Object>();
}
/**
* Returns the name of this JavaScript class, "Matrix".
*/
public String getClassName() {
return "Matrix";
}
/**
* Defines the "dim" property by returning true if name is
* equal to "dim".
* <p>
* Defines no other properties, i.e., returns false for
* all other names.
*
* @param name the name of the property
* @param start the object where lookup began
*/
public boolean has(String name, Scriptable start) {
return name.equals("dim");
}
/**
* Defines all numeric properties by returning true.
*
* @param index the index of the property
* @param start the object where lookup began
*/
public boolean has(int index, Scriptable start) {
return true;
}
/**
* Get the named property.
* <p>
* Handles the "dim" property and returns NOT_FOUND for all
* other names.
* @param name the property name
* @param start the object where the lookup began
*/
public Object get(String name, Scriptable start) {
if (name.equals("dim"))
return new Integer(dim);
return NOT_FOUND;
}
/**
* Get the indexed property.
* <p>
* Look up the element in the associated list and return
* it if it exists. If it doesn't exist, create it.<p>
* @param index the index of the integral property
* @param start the object where the lookup began
*/
public Object get(int index, Scriptable start) {
while (index >= list.size()) {
list.add(null);
}
Object result = list.get(index);
if (result != null)
return result;
if (dim > 2) {
Matrix m = new Matrix(dim-1);
m.setParentScope(getParentScope());
m.setPrototype(getPrototype());
result = m;
} else {
Context cx = Context.getCurrentContext();
Scriptable scope = ScriptableObject.getTopLevelScope(start);
result = cx.newArray(scope, 0);
}
list.set(index, result);
return result;
}
/**
* Set a named property.
*
* We do nothing here, so all properties are effectively read-only.
*/
public void put(String name, Scriptable start, Object value) {
}
/**
* Set an indexed property.
*
* We do nothing here, so all properties are effectively read-only.
*/
public void put(int index, Scriptable start, Object value) {
}
/**
* Remove a named property.
*
* This method shouldn't even be called since we define all properties
* as PERMANENT.
*/
public void delete(String id) {
}
/**
* Remove an indexed property.
*
* This method shouldn't even be called since we define all properties
* as PERMANENT.
*/
public void delete(int index) {
}
/**
* Get prototype.
*/
public Scriptable getPrototype() {
return prototype;
}
/**
* Set prototype.
*/
public void setPrototype(Scriptable prototype) {
this.prototype = prototype;
}
/**
* Get parent.
*/
public Scriptable getParentScope() {
return parent;
}
/**
* Set parent.
*/
public void setParentScope(Scriptable parent) {
this.parent = parent;
}
/**
* Get properties.
*
* We return an empty array since we define all properties to be DONTENUM.
*/
public Object[] getIds() {
return new Object[0];
}
/**
* Default value.
*
* Use the convenience method from Context that takes care of calling
* toString, etc.
*/
public Object getDefaultValue(Class<?> typeHint) {
return "[object Matrix]";
}
/**
* instanceof operator.
*
* We mimick the normal JavaScript instanceof semantics, returning
* true if <code>this</code> appears in <code>value</code>'s prototype
* chain.
*/
public boolean hasInstance(Scriptable value) {
Scriptable proto = value.getPrototype();
while (proto != null) {
if (proto.equals(this))
return true;
proto = proto.getPrototype();
}
return false;
}
/**
* Some private data for this class.
*/
private int dim;
private List<Object> list;
private Scriptable prototype, parent;
}