Java 7 Single Inheritance

single.java

// this is a bad idea, juse use slf4j

class SimpleLogger {
  void log( String message ) {
    System.out.println(getClass() + message );
  }
}

class  InfoLogger extends SimpleLogger {
  Logger log = LoggerFactory.getLogger(LogOne.class);
  
  @Override
  void log( String message ) {
    log.info( message );
  }
}

class DebugLogger extends SimpleLogger {
  Logger log = LoggerFactory.getLogger(LogOne.class);
  
  @Override
  void log( String message ) {
    log.debug( message );
  }
}

class Logged { // logged will work with any of the above implementations
  void logHelloWorldWithSimpleLogger( SimpleLogger logger ) {
    logger.log("Hello, World");
  }
}