019-spring Boot Log

I. Overview

Spring-boot supports log at info level by default.

Log levels: Trace, debug, info, warn, error, fatal, off "off"

II. Configuration Log level 2.1, configuration file configuration log level

Add in Application.properties

# logging.level.*  where * means package name or class name  root represents all Logging.level.root=debug

Ability to print out Spring-boot logs, as well as user-defined logs

Specify a class or package, others do not specify the use of the default info level

Logging.level.com.lhx.spring.springboot.service.userservice=debuglogging.level.com.lhx.spring.springboot.dao.userdao=debug

2.2, start parameter increase start parameter

--debug

Ability to print out Spring-boot log, cannot print user custom

2.3. In the Code

Configurableapplicationcontext context = Springapplication.run (App.class, "--debug=true");

Ability to print out Spring-boot log, cannot print user custom

Third, file output 1, configure the specified directory output

Logging.file=e:/tmp/my.log

2. Configure log directory "at this time log name Spring.log"

Logging.path=e:/tmp/logs

The above two, log file output, file size 10M, automatic segmentation

Iv. output Format 4.1, console and file pattern

logging.pattern.console=%-(%d{yyyy-mm-dd} [%thread])%-5level%logger{-%msg%  Nlogging. file. console=%-(%d{yyyy-mm-dd HH:mm:ss. SSS} [%thread])%-5level%logger{}-%msg%n

Five, spring log Analysis 5.1, the default native

See Spring-boot using Logback to output log files

Add Logback.xml or Logback-spring.xml (spring recommended) files to the resources below

<?XML version= "1.0" encoding= "UTF-8"?><Configuration>    <Appendername= "ConsoleLog"class= "Ch.qos.logback.core.ConsoleAppender">        <Layout>            <pattern>%-20 (%d{yyyy-mm-dd HH:mm:ss. SSS} [%thread])%-5level%logger{80}-%msg%n</pattern>        </Layout>    </Appender>    <Root Level= "DEBUG">        <Appender-refref= "ConsoleLog" />    </Root></Configuration>

5.2. Replace Log4j2

Among the use of Spring-boot-starter

        < Dependency >            < groupId >org.springframework.boot</groupId>            <  Artifactid>spring-boot-starter</artifactid>        </ Dependency >

A log reference has been added by default and should be excluded first

        <Dependency>            <groupId>Org.springframework.boot</groupId>            <Artifactid>Spring-boot-starter</Artifactid>            <Exclusions>                <exclusion>                    <groupId>Org.springframework.boot</groupId>                    <Artifactid>Spring-boot-starter-logging</Artifactid>                </exclusion>            </Exclusions>        </Dependency>

Add Log4j2.pom Configuration

        < Dependency >            < groupId >org.springframework.boot</groupId>            <  Artifactid>spring-boot-starter-log4j2</artifactid>        </dependency>

Add Log4j2.xml log4j2-spring.xml (Spring recommended) profile

<?XML version= "1.0" encoding= "UTF-8"?><Configuration>    <appenders>        <Consolename= "Console"Target= "System_out"Follow= "true">            <Patternlayoutpattern= "%d{yyyy-mm-dd HH:mm:ss. SSS} [%thread]%-5level%logger{80}-%msg%n " />        </Console>    </appenders>    <Loggers>        <Root Level= "DEBUG">            <Appender-refref= "Console" />        </Root>    </Loggers></Configuration>

Programs can be used

5.3. Related source code

View the Spring-boot-1.5.9.release.jar package to view support for the following four types of

Org.springframework.boot.loggingorg.springframework.boot.logging.javaorg.springframework.boot.logging.log4j2org.springfra Mework.boot.logging.logback

View the log level in org.springframework.boot.logging Org.springframework.boot.logging.LogLevel

 Public enum LogLevel {    TRACE, DEBUG, INFO, WARN, ERROR, FATAL, OFF}

Configuration items in: Org.springframework.boot.logging.LoggingSystemProperties class

In Org.springframework.boot.logging.logback, view Default.xml, Base.xml, File-appender.xml, console-appender.xml profiles

019-spring Boot Log