Subject:
Re: [Fwd: [Bug 13658] Changed - Rhino: null pointer exception on class with duplicate field/method]
Date:
Mon, 13 Sep 1999 20:57:32 -0400
From:
"Kurt Westerfeld" <kurt@westerfeld.com>
To:
"Norris Boyd" <norris@netscape.com>
I do have a patch for this, but it is intermixed with some other changes
that I have implemented for the get/set on Java instances (per my LC3
proposal). The bug requires changes that are a little involved actually;
basically it seems that when getting the default value for a "field and
methods" (which combines the same-named entities), the prototype of the
parent scope is deref-ed, and the parent scope is null. Hence, the scope
must be passed into the the cloned field and method values.
Also, the NativeJavaClass implementation passed "false" for isStatic on the
constructor of the FieldAndMethods Hashtable, which results in classes
having instance methods. Bad. I haven't filed a bug on that yet.
Additionally, I fixed a couple other NullPointerException nigglies thrown in
when exceptions are propagated in the same area. Finally, when getting the
default value for the field, it is helpful to convert a Scriptable to string
when that is requested (as when typing in the console).
I am attaching the changed files. The LC3++ code can be removed if you
want, which I can do for you but it will take a little longer. What is your
preference?
-----Original Message-----
From: Norris Boyd <norris@netscape.com>
To: Kurt Westerfeld <kurt@westerfeld.com>
Date: Monday, September 13, 1999 4:54 PM
Subject: [Fwd: [Bug 13658] Changed - Rhino: null pointer exception on class
with duplicate field/method]
>Kurt,
>
>Is this the bug that your patch fixes?
>
>Thanks,
>Norris
>
Turned off 'super' keyword - was letting through some cut'n'pasted java
code quietly and blowing big chunks out of the codegen/interpreter later.
Anybody know why 'super' had an interesting value here? - there was no
support for it on any path that I could see.
Subject:
Embedding the shell
Date:
Wed, 8 Sep 1999 16:01:44 -0400
From:
"Kurt Westerfeld" <kurt@westerfeld.com>
To:
"Norris Boyd" <norris@netscape.com>
Norris, please find the attached zip file containing the (minor)
modifications to the Rhino shell module that enables the shell to be
embedded in a host application.
There are two areas of change to be concerned about:
1. Any and all references to System.in/out/err have been modified to use
Main.in/out/err, which default to System.in/out/err. Methods to do a setIn,
setOut, and setErr were added. Note that in/out/err on Main were made
static public, so that the jikes compiler wouldn't complain (I had them as
static protected, but when accessed outside of the package, a warning was
issued).
2. The global and sharedGlobal static variables were made protected so
that my app can make use of them (to add extensions after an initial pass
through main()).
That's it.
I have successfully used the facility to drop a remote telnet server into
the shell interpreter, effectively giving our server a remote shell
interpreter. It's quite nice, as we have a lot of extensions to Rhino
written that blend into our server already.
PS, I am still working on the array issues, but made a lot of progress
today. I just wanted to get this stuff off my desk.
Thanks!
________________________________________________________________________
Kurt Westerfeld
Managed Object Solutions
2722 Merrilee Drive
Suite 350
Fairfax, VA 22031
Phone: 703.208.3330 x225
Fax: 703.208.3331
http://www.mosol.com
mailto:kurt@mosol.com
shell.zip
Name:
shell.zip
Type:
Zip Compressed Data (application/x-zip-compressed)
Encoding:
base64
==============================================================================
Subject:
Rhino Array Source (Fixed)
Date:
Thu, 9 Sep 1999 14:12:03 -0400
From:
"Kurt Westerfeld" <kurt@mosol.com>
To:
"Norris Boyd" <norris@netscape.com>
Attached is NativeJavaObject.java, which seems to now pass the tests supplied to me by you and Scott. Not a lot of change, but a lot of
testing and thinking was involved. <g>
PS. I also fixed a bug in reportConversionError() which was throwing an IllegalArgumentException inside of the MessageFormat class at times.
It also looks a little nicer (uses formatting from NativeJavaMethod) and closer to the C implementation.
NativeJavaObject.java
Name:
NativeJavaObject.java
Type:
Java Source File (text/java)
Encoding:
quoted-printable
The fix sort of works. But there are some new problems. I enclosed two JavaScript files, button.js and image.js.
If I load button.js first and then image.js, I got the following:
js> load("button.js");
js> load("image.js");
Ambiguous import: [JavaClass javax.swing.ImageIcon] and [JavaClass javax.swing.ImageIcon]
js> load("image.js");
Ambiguous import: [JavaClass java.net.URL] and [JavaClass java.net.URL]
js> load("image.js");
Ambiguous import: [JavaClass java.lang.System] and [JavaClass java.lang.System]
js> load("image.js");
loadImage for 0
Ambiguous import: [JavaClass java.awt.Toolkit] and [JavaClass java.awt.Toolkit]
js> load("image.js");
loadImage for 0
js>
If I load imag.js first and then button.js, I got the following:
js> load("image.js");
loadImage for 0
js: [JavaPackage java.lang.URL] is not a function.
[JavaPackage java.lang.URL] is not a function.
js> load("image.js");
js: [JavaPackage java.lang.ImageIcon] is not a function.
[JavaPackage java.lang.ImageIcon] is not a function.
js> load("image.js");
js: [JavaPackage java.lang.ImageIcon] is not a function.
[JavaPackage java.lang.ImageIcon] is not a function.
js> load("image.js");
js: [JavaPackage java.lang.ImageIcon] is not a function.
[JavaPackage java.lang.ImageIcon] is not a function.
js> load("button.js");
js: [JavaPackage java.lang.JButton] is not a function.
[JavaPackage java.lang.JButton] is not a function.
js> load("button.js");
js: [JavaPackage java.lang.JButton] is not a function.
[JavaPackage java.lang.JButton] is not a function.
js> load("image.js");
js: [JavaPackage java.lang.ImageIcon] is not a function.
[JavaPackage java.lang.ImageIcon] is not a function.
js>
It looks like something wrong in the image.js file but this should not interfere with button.js. It looks like some arbitary package objects are created, like java.lang.URL. This happened in NativeJavaPackage.get method. If a class of java.lang.URL is not found, a package object is then created. So next time the interpreter encounters URL, it somehow uses the object java.lang.URL instead of the correct class object java.net.URL.. This is one problem. The interference between button.js and jmage.js is another problem.
Howard
----- Original Message -----
From: Norris Boyd
To: \ Howard\\ Xuhua Lin
Sent: Thursday, August 12, 1999 12:58 PM
Subject: Re: ImporterTopLevel problem
Sorry I've been slow. I finished up the fix this morning and have posted it on the ftp site and checked into cvs.
Let me know if it works for you.
--Norris
\"Howard\" Xuhua Lin wrote:
Hi, Norris, what's the status of the ImporterTopeLevel problem (i.e if you use importPackage twice, you will get an "Ambiguous import" exception)? Are you still working on it? Howard
Subject:
ImporterTopLevel problem
Date:
Fri, 6 Aug 1999 15:42:50 -0400
From:
"\"Howard\" Xuhua Lin" <howard@softcom.com>
To:
"Norris Boyd" <norris@netscape.com>
CC:
"Andrew Wason" <aw@softcom.com>
Hi, The following script will cause an EvaluatorException: Ambiguous import: [JavaPackage java.awt.JButton] and [JavaPackage
java.awt.Packages.javax.swing.JButton] in the js shell:
js>importPackage(java.awt);
js>importPackage(Packages.javax.swing);
js>new JButton();.
The current JS shell will not print this exception message, even though the comment says "// Already printed message, so just fall
through". I add System.err.println(ee.getMessage()); for this exception.
The problem is that in NativeJavaPackage.get(String, Scriptable) method, if a ClassNotFoundException is caught, a
NativeJavaPackage object is created and passed back to ImporterTopLevel.get Method. So in ImporterTopLevel.get method, object v
is always not NOT_FOUND and the ambiguous exception will be thrown. Object v is supposed to be a Class object but it actually is
a Package object.
The fix can be either (1) in NativeJavaPackage.get(String, Scriptable) method, if a ClassNotFoundException is caught, return a
NOT_FOUND object (you may still create a Package object) or (2) in ImporterTopLevel.get method, make sure the returned object
from NativeJavaPackage.get method is of NativeJavaClass type.
Howard
Subject:
reflection and illegal package access
Date:
Wed, 04 Aug 1999 21:56:20 -0400
From:
Andrew Wason <aw@softcom.com>
To:
norris@netscape.com (Norris Boyd)
CC:
Howard Lin <howard@softcom.com>
If you run Rhino under JDK1.2 with a security manager:
java -Djava.security.manager=java.lang.SecurityManager
org.mozilla.javascript.tools.shell.Main
Then reflection fails for objects that are in a restricted access package
(e.g. sun.*). Rhino is reflecting based on the dynamic type of the object
instead of the declared static return type.
In this example, createImage is declared to return java.awt.Image, but it
returns sun.awt.image.OffScreenImage. Attempting to reflect this class
results in a java.security.AccessControlException for
java.lang.RuntimePermission accessClassInPackage.sun.awt.image.
Here is the script. You will need to type it in because you won't be able
to load it from a file due to the security manager.
var f = new java.awt.Frame();
f.setVisible(true);
var i = f.createImage(10,10);
Subject:
null arguments
Date:
Wed, 04 Aug 1999 13:22:35 -0400
From:
Andrew Wason <aw@softcom.com>
To:
norris@netscape.com
CC:
Howard Lin <howard@softcom.com>
When I try to pass a null argument to an interface implemented in JS, I get:
js: Cannot convert null to an object.
js: uncaught JavaScript exception:
org.mozilla.javascript.EvaluatorException: Cannot convert null to an object.
var b = new Packages.javax.swing.border.Border() {
getBorderInsets : function(c) {
return new Insets(0,0,0,0);
}
};
b.getBorderInsets(null);
Here is the stack trace where the exception is happening:
java.lang.reflect.InvocationTargetException:
org.mozilla.javascript.EvaluatorException: Cannot convert null to an object.
at
org.mozilla.javascript.tools.ToolErrorReporter.runtimeError(ToolErrorReporte
r.java:106)
at org.mozilla.javascript.Context.reportRuntimeError(Context.java:484)
at org.mozilla.javascript.Context.reportRuntimeError(Context.java:500)
at
org.mozilla.javascript.ScriptRuntime.toObject(ScriptRuntime.java:529)
at org.mozilla.javascript.Context.toObject(Context.java:1107)
at adapter0.getBorderInsets(<adapter>)
at java.lang.reflect.Method.invoke(Native Method)
at
org.mozilla.javascript.NativeJavaMethod.call(NativeJavaMethod.java,
Compiled Code)
at org.mozilla.javascript.ScriptRuntime.call(ScriptRuntime.java:1256)
at org.mozilla.javascript.Interpreter.interpret(Interpreter.java,
Compiled Code)
at
org.mozilla.javascript.InterpretedScript.call(InterpretedScript.java:49)
at
org.mozilla.javascript.InterpretedScript.exec(InterpretedScript.java:37)
at org.mozilla.javascript.Context.evaluateReader(Context.java:691)
at
org.mozilla.javascript.tools.shell.Main.processSource(Main.java, Compiled Code)
at org.mozilla.javascript.tools.shell.Main.main(Main.java:146)
Context.toObject does not allow wrapping nulls.
JavaAdapter.generateOverride should generate bytecode to check if an
argument is null and if it is not call Context.toObject.
I'll take a look at fixing this after the other JavaAdapter patches get
checked in so we don't get out of sync.
Andrew
--
Andrew Wason
SoftCom, Inc.
aw@softcom.com
* Accept patch from Andrew Wason <aw@softcom.com>:
Subject:
Re: partial interface problem
Date:
Wed, 04 Aug 1999 13:04:37 -0400
From:
Andrew Wason <aw@softcom.com>
To:
norris@netscape.com
CC:
Howard Lin <howard@softcom.com>
>I'm having a problem implementing a Java interface in JS where I don't
>implement all the methods, and one of the methods I don't define returns
>non-void.
I have a patch for this. I generate bytecode in
JavaAdapter.generateReturnResult to check the return type on the stack from
JavaAdapter.callMethod. If it is Undefined, return null.
I'm not positive this is the right way to fix this - maybe it should be
fixed closer to the source (e.g. prevent callMethod from returning
Undefined to begin with)
Andrew
--
Andrew Wason
SoftCom, Inc.
aw@softcom.com
