A Java class loader works by converting a class file into a Java class that can be executed by the JVM. The three primary types of class loaders in Java are as follows: ...

Create packages, import packaged classes and interfaces into your programs, move packages, and encapsulate them in jar files.

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.

Keep in mind that not every JAR file is runnable. Some JAR files are just support files intended to be used by other Java apps. For a JAR file to run, the JAR itself must contain at least one class ...

Since I have done most of my coding for classes (and almost exclusively in Java), I have always just run my programs through the compiler and never had to worry about actually setting it up to run ...