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.

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).

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 ...

Java’s collections like arrays and lists are foundational building blocks. Functional programming techniques are at times the ideal way to work with these collections.