Abstract method in Enums

Did you know that you can do that?

private static enum DynamicProperty {

    cacheManagerName {
        @Override
        void applyChange(final PropertyChangeEvent evt, final RuntimeCfg config) {
            config.cacheManagerName = (String) evt.getNewValue();
        }
    },
    defaultCacheConfiguration {
        @Override
        void applyChange(final PropertyChangeEvent evt, final RuntimeCfg config) {
            LOG.debug("Default Cache Configuration has changed, previously created caches remain untouched");
        }
    };

    abstract void applyChange(PropertyChangeEvent evt, RuntimeCfg config);
}

I think it’s nice because it allows you to customize Enum’s behavior or perform other actions on use.

Piece of code taken from EhCache Configuration (line 118 and further).