New methods in java.util.concurrent.ConcurrentHashMap

This rule flags classes that extend the java.util.concurrent.ConcurrentHashMap class. Java 8 enhanced the concurrency utilities with new classes and interfaces in the java.util.concurrent package, including over 30 new methods in the ConcurrentHashMap class. If you extend the ConcurrentHashMap class, review your implementation to assess how it needs to be changed to accommodate the new methods.

Another change to the Java 8 ConcurrentHashMap class is the introduction of the ConcurrentHashMap.KeySetView class. The keySet method was changed to return this new KeySetView class. Review whether your implementation overrides the keySet method, and make any necessary adjustments to return this new type.

For information about changes in the java.util.concurrent package, see Concurrency Utilities Enhancements in Java SE 8.

For additional information, see:

• Class java.util.concurrent.ConcurrentHashMap<K,V> Java documentation
• Class java.util.concurrent.ConcurrentHashMap.KeySetView<K,V> Java documentation