Reference objects aren't just useful when memory is at a premium; they can also be used to provide slick caching abilities to any application.

You might know that Java passes by value, but it helps to understand why. Here's what happens when you pass mutable and immutable object references in Java.

Copying objects is a common Java programming operation that has one serious trap. Here's how to avoid copying from an object reference and only copy the instance and values you want.