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/* -*- Mode: java; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
import org.mozilla.javascript.*;
import org.mozilla.javascript.annotations.JSFunction;
import org.mozilla.javascript.annotations.JSGetter;
/**
* An example host object class.
*
* Here's a shell session showing the Foo object in action:
*
* js> defineClass("Foo")
* js> foo = new Foo(); A constructor call, see Foo below.
* [object Foo] The "Foo" here comes from getClassName.
* js> foo.counter; The counter property is defined by the defineProperty
* 0 call below and implemented by the getCounter
* js> foo.counter; method below.
* 1
* js> foo.counter;
* 2
* js> foo.resetCounter(); Results in a call to resetCounter.
* js> foo.counter; Now the counter has been reset.
* 0
* js> foo.counter;
* 1
* js> bar = new Foo(37); Create a new instance.
* [object Foo]
* js> bar.counter; This instance's counter is distinct from
* 37 the other instance's counter.
* js> foo.varargs(3, "hi"); Calls varargs.
* this = [object Foo]; args = [3, hi]
* js> foo[7] = 34; Since we extended ScriptableObject, we get
* 34 all the behavior of a JavaScript object
* js> foo.a = 23; for free.
* 23
* js> foo.a + foo[7];
* 57
* js>
*
*
* @see org.mozilla.javascript.Context
* @see org.mozilla.javascript.Scriptable
* @see org.mozilla.javascript.ScriptableObject
*
* @author Norris Boyd
*/
public class Foo extends ScriptableObject {
private static final long serialVersionUID = -3833489808933339159L;
/**
* The zero-parameter constructor.
*
* When Context.defineClass is called with this class, it will
* construct Foo.prototype using this constructor.
*/
public Foo() {
}
/**
* The Java method defining the JavaScript Foo constructor.
*
* Takes an initial value for the counter property.
* Note that in the example Shell session above, we didn't
* supply a argument to the Foo constructor. This means that
* the Undefined value is used as the value of the argument,
* and when the argument is converted to an integer, Undefined
* becomes 0.
*/
public Foo(int counterStart) {
counter = counterStart;
}
/**
* Returns the name of this JavaScript class, "Foo".
*/
@Override
public String getClassName() {
return "Foo";
}
/**
* The Java method defining the JavaScript resetCounter function.
*
* Resets the counter to 0.
*/
@JSFunction
public void resetCounter() {
counter = 0;
}
/**
* The Java method implementing the getter for the counter property.
*
* If "setCounter" had been defined in this class, the runtime would
* call the setter when the property is assigned to.
*/
@JSGetter
public int getCounter() {
return counter++;
}
/**
* An example of a variable-arguments method.
*
* All variable arguments methods must have the same number and
* types of parameters, and must be static.
* @param cx the Context of the current thread
* @param thisObj the JavaScript 'this' value.
* @param args the array of arguments for this call
* @param funObj the function object of the invoked JavaScript function
* This value is useful to compute a scope using
* Context.getTopLevelScope().
* @return computes the string values and types of 'this' and
* of each of the supplied arguments and returns them in a string.
*
* @see org.mozilla.javascript.ScriptableObject#getTopLevelScope
*/
@JSFunction
public static Object varargs(Context cx, Scriptable thisObj,
Object[] args, Function funObj)
{
StringBuffer buf = new StringBuffer();
buf.append("this = ");
buf.append(Context.toString(thisObj));
buf.append("; args = [");
for (int i=0; i < args.length; i++) {
buf.append(Context.toString(args[i]));
if (i+1 != args.length)
buf.append(", ");
}
buf.append("]");
return buf.toString();
}
/**
* A piece of private data for this class.
*/
private int counter;
}