[log frame]

Log framework

SpringBoot： The bottom is Spring frame ,Spring The frame defaults to JCL;‘
SpringBoot choose SLF4j and logback;

Log usage

1、 The default configuration
SpringBoot By default, the log is configured for us ;

// Recorder 
    Logger logger = LoggerFactory.getLogger(getClass());
    @Test
    public void contextLoads() {
    
        //System.out.println();
        // Level of logging ;
        // From low to high  trace<debug<info<warn<error
        // You can adjust the log level of the output ; Logs will only take effect at this level at a later high level 
        logger.trace(" This is a trace journal ...");
        logger.debug(" This is a debug journal ...");
        //SpringBoot The default is info Grade , Use if you don't specify a level SpringBoot Default specified level ;root Level 
        logger.info(" This is a info journal ...");
        logger.warn(" This is a warn journal ...");
        logger.error(" This is a error journal ...");
    }

SpringBoot Modify the default configuration of the log ：

logging.level.com.atguigu=trace
#logging.path=
#  Do not specify the path to generate... Under the current project springboot.log journal 
#  You can specify the full path ;
#logging.file=G:/springboot.log
#  Create... Under the root path of the current disk spring Folder and inside log Folder ; Use  spring.log  As the default file 
logging.path=/spring/log
#  The format of the log output in the console 
logging.pattern.console=%d{
    yyyy‐MM‐dd} [%thread] %‐5level %logger{
    50} ‐ %msg%n
#  Specify the format of log output in the file 
logging.pattern.file=%d{
    yyyy‐MM‐dd} === [%thread] === %‐5level === %logger{
    50} ==== %msg%n

Specify the configuration

Drop the configuration file of each log framework to the classpath ;SpringBoot It doesn't use his default configuration
logback.xml： Directly recognized by the log framework ;
logback-spring.xml： The log framework does not directly load the log configuration items , from SpringBoot Parsing log configuration , have access to SpringBoot Advanced Profile function

logback-spring.xml

<?xml version="1.0" encoding="UTF-8"?>
<!-- scan： When this property is set to true when , If the configuration file changes , Will be reloaded , The default value is true. scanPeriod： Set the time interval between changes in the monitoring profile , If no time unit is given , The default unit is milliseconds scan by true when , This property takes effect . The default time interval is 1 minute . debug： When this property is set to true when , Will print out logback Internal log information , Real-time view logback Running state . The default value is false. -->
<configuration scan="false" scanPeriod="60 seconds" debug="false">
    <!--  Define the log root  -->
    <property name="LOG_HOME" value="/app/log" />
    <!--  Define log file name  -->
    <property name="appName" value="atguigu-springboot"></property>
    <!-- ch.qos.logback.core.ConsoleAppender  Indicates console output  -->
    <appender name="stdout" class="ch.qos.logback.core.ConsoleAppender">
        <!--  Log output format ： %d Means date time , %thread Represents the thread name , %-5level： The level is shown from the left 5 Character width  %logger{50}  Express logger The longest name 50 Characters , Otherwise, divide by periods . %msg： Log message , %n Is a newline  -->
        <layout class="ch.qos.logback.classic.PatternLayout">
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} ----> [%thread] ---> %-5level %logger{50} - %msg%n</pattern>
            <!--<springProfile name="dev"> <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} &#45;&#45;&ndash;&gt; [%thread] -&ndash;&gt; %-5level %logger{50} - %msg%n</pattern> </springProfile> <springProfile name="!dev"> <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} ==== [%thread] ==== %-5level %logger{50} - %msg%n</pattern> </springProfile>-->
        </layout>
    </appender>

    <!--  Scroll record file , First log to the specified file , When a condition is met , Log to other files  -->  
    <appender name="appLogAppender" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <!--  Specify the name of the log file  -->
        <file>${LOG_HOME}/${appName}.log</file>
        <!--  When rolling happens , decision  RollingFileAppender  act , It involves moving and renaming files  TimeBasedRollingPolicy：  The most common rolling strategy , It makes rolling strategies based on time , Responsible for rolling as well as starting rolling . -->
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <!--  The storage location and file name of the file generated during scrolling  %d{yyyy-MM-dd}： Scroll through the logs by day  %i： When the file size exceeds maxFileSize when , according to i Scroll through the files  -->
            <fileNamePattern>${LOG_HOME}/${appName}-%d{yyyy-MM-dd}-%i.log</fileNamePattern>
            <!--  Optional nodes , Control the maximum number of archive files that are retained , Delete old files if the number exceeds . Suppose you set scrolling every day ,  And maxHistory yes 365, Save only recent 365 Days of documents , Delete old files before . Be careful , Deleting old files is ,  Directories created for archiving will also be deleted . -->
            <MaxHistory>365</MaxHistory>
            <!--  When the log file exceeds maxFileSize The designated size is , According to the above %i Scroll the log file   Note the configuration here SizeBasedTriggeringPolicy Scrolling by file size is not possible , You have to configure timeBasedFileNamingAndTriggeringPolicy -->
            <timeBasedFileNamingAndTriggeringPolicy class="ch.qos.logback.core.rolling.SizeAndTimeBasedFNATP">
                <maxFileSize>100MB</maxFileSize>
            </timeBasedFileNamingAndTriggeringPolicy>
        </rollingPolicy>
        <!--  Log output format ： -->     
        <layout class="ch.qos.logback.classic.PatternLayout">
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [ %thread ] - [ %-5level ] [ %logger{50} : %line ] - %msg%n</pattern>
        </layout>
    </appender>

    <!-- logger It is mainly used to store log objects , You can also define the log type 、 Level  name： A match logger Type prefix , The first half of the bag  level： Log level to log , Include  TRACE < DEBUG < INFO < WARN < ERROR additivity： The function is to children-logger Whether to use  rootLogger Configured appender For the output , false： Means only the current logger Of appender-ref,true：  At present logger Of appender-ref and rootLogger Of appender-ref Are effective  -->
    <!-- hibernate logger -->
    <logger name="com.atguigu" level="debug" />
    <!-- Spring framework logger -->
    <logger name="org.springframework" level="debug" additivity="false"></logger>

    <!-- root And logger It's father son relationship , If there is no special definition, it defaults to root, Any class can only be associated with one logger Corresponding ,  Or defined logger, Or root, The key to judgment is to find this logger, And then judge this logger Of appender and level. -->
    <root level="info">
        <appender-ref ref="stdout" />
        <appender-ref ref="appLogAppender" />
    </root>
</configuration> 

If you use logback.xml As log profile , And use profile function , There will be the following mistakes
no applicable action for [springProfile]