why `java.lang.SecurityException: Prohibited package name: java` is required?

Question

I created a class \"String\" and placed that in package \"java\" [ actually i wanted to create java.lang to see which class is loaded by classLoader as

Answer 1

Probably during refactoring/patch applying/etc. you have added to package name word 'java', which is usually a folder that contains packages.

So you could end with the structure: src->main->java->java.com.yourpackage.name

It might also happens for test: src->main->test->java->java.com.yourpackage.name

Verify it in your IDE and remove "java." part