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 Collections class’s methods for obtaining empty collections are preferable to use of Collections ‘s similarly named fields for that same purpose because of the type safety the methods provide.

Java collection classes allow a developer to keep track of contained items in one of two ways, either by an indexed count or a key. This creates an obvious limitation where multiple values can’t be ...

It is similar to the ArrayList, but with two differences. Vector is synchronized. Vector 是线程安全的。 Java Vector contains many legacy methods that are not the part of a collections framework. E element() ...

With the sequenced collections proposal, all of the new methods declared in the new interfaces have default implementations. Sequenced collections would be added to the standard edition of Java ...