jython-users

[Jython-users] Re: JDK 1.1.8 [was JDK Recommendation]

[ron g. <rg...@un...>]

    I downloaded JDK 1.1.8 as suggested and eventually was able to produce a
simple applet that extends one of my classes and loads in Netscape
(eventually!) and IE.  Each gave errors, however, described below.  Can someone
tell me why these are occuring, and what I should do about them?

Under IE,  I don't know how to capture the output from the Java Console, but
the messages were

com.ms.security.SecurityExceptionEx[org/python/core/Py.initProperties]:  Unable
to access system properties.

as well as a message indicating an inability to find the java.util.HashMap
class (as with Netscape, below)



Under Netscape:
Netscape Communications Corporation -- Java 1.1.5

Type '?' for options.

Symantec Java! ByteCode Compiler Version 210.065
Copyright (C) 1996-97 Symantec Corporation
# Error: Invalid digital signature file (-7885)
# jar file: C:\DOCUME~1\ron\LOCALS~1\Temp\jzipB72T.TMP
# path:     C:\DOCUME~1\ron\LOCALS~1\Temp\jzipB72T.TMP
# Error: internal error - error in manifest file (-1)
# jar file: C:\DOCUME~1\ron\LOCALS~1\Temp\jzipB72T.TMP
# path:     /D|/HomePage/Illuminations/Java/
# Verifier error org/python/core/InternalTables2.commitTemp()V: Cannot find
class java/util/HashMap
# Verifier error
org/python/core/MakeProxies.makeProxy(Ljava/lang/Class;Ljava/util/Vector;Ljava/lang/String;Lorg/python/core/PyObject;)Ljava/lang/Class;:
Cannot find class org/python/compiler/ProxyMaker
java.lang.NullPointerException: invalid peer

  at java.awt.Component.hide(Compiled Code)

* at netscape.applet.DerivedAppletFrame$DestroyAppletEvent.dispatch(Compiled
Code)

  at java.awt.EventDispatchThread$EventPump.dispatchEvents(Compiled Code)

  at java.awt.EventDispatchThread.run(Compiled Code)

  at netscape.applet.DerivedAppletFrame$AppletEventDispatchThread.run(Compiled
Code)



>
>
> Message: 5
> From: Don Coleman <don...@em...>
> To: 'ron greene' <rg...@un...>, jyt...@li...
> Subject: RE: [Jython-users] JDK recommendation
> Date: Mon, 18 Jun 2001 09:11:13 -0400
>
> You should still be able to download JDK1.1.8_007 from Sun, but I think
> 1.3.1 will work fine as long as you don't use any of the 1.2 specific
> classes (e.g. Swing, Collections, etc).
>
> > -----Original Message-----
> > From: ron greene [mailto:rg...@un...]
> > Sent: Monday, June 18, 2001 10:04 AM
> > To: jyt...@li...
> > Subject: [Jython-users] JDK recommendation
> >
> >
> > I'm a new would-be convert to Jython.  I've been developing a
> > series of
> > Java applets for physics education, and think that I would be more
> > productive (eventually) with Jython.  I got my Jython installation up
> > and running with Sun's SDK 1.3.1, but then discovered
> > (obviously should
> > have thought about this) that what I produce with it does not
> > run under
> > IE 5.x or Netscape 4.7x, the two most common browsers for my audience.
> > I need a recommendation for a 1.1 JDK that someone has actually tested
> > with the above browsers.  Thanks.
> >
> >         ron greene
> >
> >

Re: [Jython-users] Re: JDK 1.1.8 [was JDK Recommendation]

[D-Man <ds...@ri...>]

On Mon, Jun 18, 2001 at 03:53:49PM -0500, ron greene wrote:
| I downloaded JDK 1.1.8 as suggested and eventually was able to
| produce a simple applet that extends one of my classes and loads in
| Netscape (eventually!) and IE.  Each gave errors, however, described
| below.  Can someone tell me why these are occuring, and what I
| should do about them?
| 
| Under IE,  I don't know how to capture the output from the Java
| Console, but the messages were
| 
| com.ms.security.SecurityExceptionEx[org/python/core/Py.initProperties]:  Unable
| to access system properties.

Not sure about this.

| as well as a message indicating an inability to find the java.util.HashMap
| class (as with Netscape, below)

http://java.sun.com/products/jdk/1.2/docs/api/java/util/HashMap.html

Since:
    JDK1.2


java.util.HashMap didn't exist until Java 2.  Use java.util.Hashtable instead.


| Under Netscape:
| Netscape Communications Corporation -- Java 1.1.5

_old_ JVM ;-).

Netscape 6 uses JDK 1.3.0 (not that you can tell your users to upgrade
their web browser anyways).

-D

[Jython-users] Problems with Java inner classes

[<ma...@la...>]

I was trying out a simplistic example that I /thought/ was something I'd done 
before, but I can't get it to work.

Assuming a piece of Java that looks like this:

public class A {
  public A() { System.out.println("new A"); }
  private void mA() { System.out.println("A's method"); }
  public class B {
    public B() { System.out.println("new B"); }
    private void mB() { System.out.println("B's method"); }
    public class C {
      public C() { System.out.println("new C"); }
      public void mC() {
        System.out.println("C's method");
        mA();
        mB();
      }
    }
  }
}


How do I do, in Jython, the equivalent of this code:

public class Foo {
  public static void main(String[] args) {
    A a = new A();
    // a.mA();		// private mA: can't reach from here
    A.B b = a.new B();
    // b.mB();		// private mB: can't reach from here
    A.B.C c = b.new C();
    c.mC();		// public mC should have access to mA and mB
  }
}


My efforts at this are running into all kinds of visibility problems - 
instantiating an "A" is fine, but beyond that I'm not getting what I want.


Feeling el-stupido,

Mats