code: protected static String generateTag() {
  		StackTraceElement[] elements = Thread.currentThread().getStackTrace();
  
  		String currentPath = elements[4].getClassName();
  		String method = elements[4].getMethodName();
  		int line = elements[4].getLineNumber();
  
  		String tag = currentPath + ", " + method + " (line " + line + ")";
  		tag = tag.substring(tag.lastIndexOf(".") + 1);
  
  		return tag;
  	}
docs: generate tag.
  
  @return tag of logger