BoxWrap2d: Shape and its subclasses not found

mpetersen3

BoxWrap2d: Shape and its subclasses not found

in Contributed Library Questions • 2 years ago

I have been trying to learn box2d through the boxwrap2d tutorials by philho here: http://processing.org/discourse/yabb2/YaBB.pl?num=1247034244

In my code I have run some of the basic examples ie. swinging chain, so processing is finding the library without a problem.

import org.jbox2d.collision.*;

however this line (below) still returns an error saying "Cannot find a class or type named "org.jbox2d.collision.Shape"

org.jbox2d.collision.Shape[] shapes = world.query(aabb, 10);

Any ideas on why this is happening/how to fix it?

Thanks

Replies(9)

PhiLho

Re: BoxWrap2d: Shape and its subclasses not found

2 years ago

What version of BoxWrap2D do you use?

mpetersen3

Re: BoxWrap2d: Shape and its subclasses not found

2 years ago

I looked around in the files I have and didn't find the version, but looking at the source code, I saw that the package was listed as org.jbox2d.p5 so I tried to use

org.jbox2d.p5.collision.Shape s;

but this still didn't work. I got the library from http://jbox2d.nfshost.com/processing/

PhiLho

Re: BoxWrap2d: Shape and its subclasses not found

2 years ago

Strange. I looked at this file, it is roughly the same version than mine (December 2008) and both have the org.jbox2d.collision.Shape class.
Not sure what is going on, if other classes are found.

mpetersen3

Re: BoxWrap2d: Shape and its subclasses not found

2 years ago

The one I have has the file modified date as May 2008, so maybe between then and December they added the shape class?

PhiLho

Re: BoxWrap2d: Shape and its subclasses not found

2 years ago

I looked at the dates inside the jar file itself. You can open it with an archive viewer and look at the path, you should find the Shape.class file. I downloaded at the link you gave (regular BoxWrap site) just today.

mpetersen3

Re: BoxWrap2d: Shape and its subclasses not found

2 years ago

Yea I did the same, Shape.class is definitely there. Right now I have the boxwrap2d file in /applications/processing.app/contents/resources/java/libraries/ I also added the jar to the libraries file in the sketchbook, to no luck.

p.s. object collisions are working without any problem

mpetersen3

Re: BoxWrap2d: Shape and its subclasses not found

2 years ago

After seeing that Shape.class was definitely in my jar for boxwrap2d, I realized that I may have a conflict since I had installed pbox2d also, which contains jbox2d also. I tried removing the pbox2d library and adding

org.jbox2d.collision.Shape s;

and now I am getting a null pointer exception instead of cannot find class or type

p.s. I just tried removing org.jbox2d.collision.Shape s; and now I am getting the same error, so it must have been using the pbox2d library, now I need to figure out how to make it reference the boxwrap2d library

p.p.s I tried using the import menu and clicking on boxwrap2d, but I am still getting the null pointer error

below is the error

java.lang.NullPointerException

at processing.app.debug.Compiler.contentsToClassPath(Compiler.java:705)

at processing.app.Sketch.preprocess(Sketch.java:1385)

at processing.app.Sketch.preprocess(Sketch.java:1205)

at processing.app.Sketch.build(Sketch.java:1568)

at processing.app.Sketch.build(Sketch.java:1553)

at processing.app.Editor$DefaultRunHandler.run(Editor.java:1485)

at java.lang.Thread.run(Thread.java:655)

PhiLho

Re: BoxWrap2d: Shape and its subclasses not found

2 years ago

Wow, the NPE isn't in your code but at compilation phase, meaning there is a bug in Processing's application, and a serious issue with your settings (class path?). Have you tried to restart Processing after removing pbox2d?

mpetersen3

Re: BoxWrap2d: Shape and its subclasses not found

2 years ago

I hadn't tried restarting processing, but doing so fixed the issue. Many thanks to you

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