Have you ever wondered why the java.util.Collections class includes various “empty” class methods, which return immutable empty collections and immutable empty iterators? This post answers ...

The Java Collections Framework (JCF), introduced in 1998 in JDK 1.2, is quickly becoming the standard for storing dynamic data in Java systems. Many new APIs use JCF’s container interfaces to ...

The Set interface inherits its methods from Collection (java.util.Collection) and contains only those methods. In addition to sets, there are queues (java.util.Queue) and maps (java.util.Map).

At the base of the Framework are the interfaces java.util.Collection and java.util.Map. The Collection interface represents just a group of objects, with no particular order or restriction.