I have an application and I need to secure/prevent my application source code.
I need that no one can get my application code by using any of the tool with the help of apk file.

I found that by using below steps, someone can get the application source code from apk file.
i.e. If someone get the apk file so He/She can easily find out the source code of an application by using its apk.

By following this link, you can easily get the source code from apk file : 
[how to extract code of apk file](https://stackoverflow.com/questions/7888102/how-to-extract-code-of-apk-file)

I just want to protect my application source code.

Thanks in advance...