Item 69: Prefer concurrency utilities to wait and notify

The first edition of this book devoted an item to the correct use of wait and notify (Bloch01, Item 50). Its advice is still valid and is summarized at end of this item, but this advice is far less important than it once was. This is because there is far less reason to use wait and notify. As of release 1.5, the Java platform provides higher-level concurrency utilities that do the sorts of things you formerly had to hand-code atop wait and notify. Given the difficulty of using wait and notify correctly, you should use the higher-level concurrency utilities instead.

The higher-level utilities in java.util.concurrent fall into three categories: the Executor Framework, which was covered only briefly in Item 68; concurrent collections; and synchronizers. Concurrent collections and synchronizers are covered briefly in this item.