java.lang: A collection of language-related classes, such as Object and String, organized in the java package’s lang subpackage; java.lang.ref: A collection of reference-related language classes ...

Newcomers to Java packages often become frustrated by “no class definition found” and other errors. This frustration can be partly avoided by understanding how the JVM looks for reference types.

Now our basic class structure, which is able to manipulate headers of RPM packages, is in place, and it would be a good idea to add a minimal GUI interface to it. We will build this very simple ...

Sealed classes make Java an even more powerful and expressive language and set the stage for even more sophisticated techniques such as pattern matching, which we'll explore in a subsequent article. A ...