Traits in Java 8

traits.java

interface Logger {
    default void log(String message ) {
        _logger().info( message );
    }
    
    Logger _logger();
}
 
class  InfoLogger implements Logger 
    Logger log = LoggerFactory.getLogger(InfoLogger.class);
    @Override
    Logger _logger() {
        return log;
    }
}
 
class DebugLogger implements Logger {
    Logger log = LoggerFactory.getLogger(DebugLogger.class);
    @Override
    Logger _logger() {
        return log;
    }
}
 
class Logged { // logged will work with any of the above implementations
  void logHelloWorldWithSimpleLogger( Logger logger ) {
    logger.log("Hello, World");
  }
}