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.

This post explains how to use classes in Java to build objects and organize your code. Also learn: constructors, static methods, and more!

It is also possible to instantiate a JRuby interpreter directly from Java, but as this ties your Java code to Ruby-specific Java wrapper classes, it’s best to stick with BSF/JSR 223.

Enterprise Java specialist Steve Haines joins the Open source Java projects series this month with an introduction to Java Caching System (JCS), a robust enterprise-level caching solution.