Here's how to make classes, fields, methods, constructors, and objects work together in your Java programs.

It is easy to generate Java classes using the xjc binding compiler provided with the Oracle’s JDK 7 implementation. This is shown in the next screen snapshot.

However, the Java Platform provides a data structure that greatly simplifies the use of reference objects like this, called the java.util.WeakHashMap class. WeakHashMap works exactly like a hash ...