SpringBoot log principle, log implementation

SpringBoot log principle, log implementation, log application

Log facade (abstract layer of logs); logging-abstract.jar
can import specific log implementations into the project; our previous log frameworks are all implemented abstract layers
Log framework on the market
Log facade selection: SLF4J (one of the other two log facades is not suitable, and the other has not been updated for a long time)
Log implementation choice: Logback
SpringBoot: The bottom layer uses the Spring framework, and the Spring framework uses JCL by default, and SpringBoot uses SLF4J and Logback

How to use SLF4j in the system

In future development, the call of the logging method should not directly call the log implementation class, but call the method in the abstract layer of the log.

Import the implementation jar of slf4j and logback into the system

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class HelloWorld {
    
    
  public static void main(String[] args) {
    
    
    Logger logger = LoggerFactory.getLogger(HelloWorld.class);
    logger.info("Hello World");	
  }
}

Icon:
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Each log implementation framework has its own configuration file. After the configuration file uses slf4j, the configuration file uses the log to implement the framework's own configuration file ;

Remaining problem

Different frameworks use different log implementations
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How to unify all logs in the system to slf4j

Exclude all other log frameworks in the system first
Replace the original log framework with an intermediate package
We import other implementations of slf4j

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to sum up:

The bottom layer of SpringBoot also uses slf4j + logback for logging.
SpringBoot also replaced other logs with slf4j
The replacement package is used in the middle to realize the effect of civet cat for prince
If we want to introduce other frameworks, we must remove the log dependency of this framework. The introduction of SpringBoot into the Spring framework also removes the log dependency of the Spring framework.
The SpringBoot framework can automatically adapt to all logs, and the bottom layer uses slf4j + logback to record logs. When introducing other frameworks, you only need to remove the log dependencies that this framework depends on.

Log usage

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 Logger logger = LoggerFactory.getLogger(ReviewerApplicationTests.class);
    @Test
    public void loggerTest(){
    
    

        logger.trace("trace级别日志");
        logger.debug("debug级别日志");
        logger.info("info级别日志");
        logger.warn("warn级别日志");
        logger.error("error级别日志");
    }

The default is the log of the info sector

#修改日志级别
logging.level.com.ebusiness.reviewer=trace
#设置日志输出位置，不指定路径，就在当前项目下生成，也可以指定路径
logging.file.path=springBoot.log

logging.file.path=/Users/apple/Desktop

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You can also set the format of log printing