Java Classloading

Question

I have a same class belonging to 2 different packages.

package x1.y1.Class
packgage x2.y2.Class

Is it possible that if I am invoking a x1.y1.Class via classloader, x2.y2.Class loads instead?

• Jon Skeet: Do you mean accidentally? Or is this what you're trying to achieve?
• vegeta: yups.. accidentally.. is ther any probability
• TheLostMind: No.. Unless you are doing it wrong it won't happen.

Answer 1

Simply said, no (unless you unintentionally load the wrong one).

Classes are loaded by their fully-qualified class-name, which includes the package (e.g. x1.y1.Class)

Answer 2

No, it can't happen, for two reasons:

• The classloader finds the class by package, by looking in the right place
• Even if you accidentally put a class in the wrong place, the class file itself includes the package name, and this is checked during class loading.

I've just tried doing this deliberately, replacing p1/Foo.class with the file for class p2.Foo, and received the following error:

Exception in thread "main" java.lang.NoClassDefFoundError: p1/Foo (wrong name: p2/Foo)

If you wanted to do this, you'd need a classloader which deliberately looked in the wrong location, and then modified the bytecode it loaded.