Minor Description
http://checkstyle.sourceforge.net/config_coding.html#MissingSwitchDefault requires that every switch statement has a default clause. In our code some switch statements enumerate all possible cases (for example, in enum) but don't have a default to protect against newly appearing cases. Others don't enumerate all possible cases. I plan to add missing cases to each enumeration (so that preserves current behavior for existing cases) and add default clause which throws exception (like in D:\incubator-reef\lang\java\reef-common\src\main\java\org\apache\reef\runtime\common\driver\task\TaskRepresenter.java, line 109).