First make a new folder and put that .apk file (which you want to extract for getting the source code) into that folder. Now you have to change the name of that .apk file with extension .zip. Also ...

If a Java file contains multiple classes, the main method should be defined in the first class in the source file.. A file executed with java can have multiple public classes. This is opposed to ...

A Java compiler takes a text file and compiles it into a platform-independent Java file, meaning the compiled code can run on any OS. Learn how it works. ... The programmer then runs a compiler for ...