Log4j 面试题与答案

问题 11. What are the Pros and Cons (advantages and disadvantages) of Logging?

Following are the Pros and Cons of Logging:

• Logging is an important component of software development. A well-written logging code offers quick debugging, easy maintenance, and structured storage of an application's runtime information.
• Logging does have its drawbacks also. It can slow down an application. If too verbose, it can cause scrolling blindness. To alleviate these concerns, log4j is designed to be reliable, fast, and extensible.
• Since logging is rarely the main focus of an application, the log4j API strives to be simple to understand and use.

问题 12. What is the purpose of DEBUG log level?

The DEBUG log level designates fine-grained informational events that are most useful to debug an application.

问题 13. What is the purpose of the ERROR log level?

The ERROR log level designates error events that might still allow the application to continue running.

问题 14. What is the purpose of the FATAL log level?

The FATAL log level designates very severe error events that will presumably lead the application to abort.

问题 15. What is the purpose of the INFO log level?

The INFO log level designates informational messages that highlight the progress of the application at a coarse-grained level.