Editing .class files

[JavaNoob84]

I have a couple of executable jar files that are filled with a bunch of .class files. These 2 jars are included as libraries in the java build path of the project.
I want to edit those .class files inside those jars. Even after I unchecked read only, I still cannot edit them in Eclipse. I can open them, but nothing happens when I type. Is it possible to edit those somehow?

Thanks.

[DarrylBurke]

What do you expect to achieve by editing the bytecode?

db

[JavaNoob84]

I want to change a bunch of JOGL 1 import statements to JOGL 2.0 equivalents and see if the code still works.
I mean I see all the code inside each .class in eclipse, just can't change it.

[DarrylBurke]

Import statements don't exist in a .class file. They are just semantic sugar that saves you the trouble of having to specify the fully qualified class name every time it is used.

Whatever you're seeing, it's not imports.

If JOGL 2.0 is 100% backward compatible with earlier versions, I think you should be able to change which version your program uses by manipulating their availability on the classpath.

db

[JavaNoob84]

Yeah I sort of figured it took some sort of decompiler and wasn't about to mess this that since I have the source files for those jars. JOGL 2.0 is not backward compatible though. Anyone has ever gone through an exercise of getting through that?

[DarrylBurke]

If you have the source files, why are you even thinking about editing .class files?

db

[JavaNoob84]

Didn't know where they were at the time.

[DarrylBurke]

Ah, ok. Problem solved then?

db

[JavaNoob84]

I'd say so. Thanks.

[JosAH]

Eclipse is quite clever when it comes to showing a .class file to a user: if it can find the source of that file it shows the source as a read only file; if it can't find any source, it partly decompiles the .class file (as javap -c would) and shows that, also as a read only file.

kind regards,

Jos