Attach the Source in Eclipse of a jar

Issue

I added a Student.jar into my Build Path in my eclipse like this-

Right click on the project->BuildPath->Configure Build Path->Libraries->Add External Jars

There is one class named StudentTest in Student.jar file. When I was debugging my code in eclipse, I stepped into that StudentTest class in the Student.jar.

And after that eclipse shows me like this-

The JAR file S:\some_location\Student.jar has no source attachment. You can attach the source by clicking Attach Source below

Now I am not sure how should I attach the source in my eclipse. And from where? Can anyone provide me step by step what I need to do.

Update:- I tried unzipping the Student.jar and I got Student folder. And after that I tried pointing the source to Student folder But still I am not able to see the class properly so that I can debug it properly, it shows the same above behavior.

Solution

A .jar file usually only contains the .class files, not the .java files they were compiled from. That's why eclipse is telling you it doesn't know the source code of that class.

"Attaching" the source to a JAR means telling eclipse where the source code can be found. Of course, if you don't know yourself, that feature is of little help. Of course, you could try googling for the source code (or check wherever you got the JAR file from).

That said, you don't necessarily need the source to debug.

Answered By - meriton