When compiling class initializers and class initialization blocks, the Java compiler stores the compiled bytecode (in top-down order) in a special method named <clinit>().

Packages can store classes and interfaces, as well as subpackages, which are packages nested within other packages. A package has a name, which must be a non-reserved identifier; for example, java.

Sealed classes in Java let developers limit the creation and use of subclasses and preserve the class hierarchy. Here is how sealed classes in Java work.