Spring MVC 学习笔记6 SLF4J Logback 日志

Simple Logging Facade for Java(SL4J)

SLF4J 提供了一组抽象接口，在部署应用时后端可以选择不同的日志框架，而无需更改已有代码。

Logback 是项目 Log4j 的后继。它由三个模块组成：logback-core, logback-classic, logback-access。其中 logback-core 是基础模块。logback-classic 是 log4j 的改良版，是 slf4j api 的原生实现，可以方便地更换成其它日志框架。logback-access 模块与 Servlet 容器集成提供Http-access 日志的功能。

Spring 默认使用 Jakarta Commons Logging，但可以切换成其它日志框架。

首先移除 spring-core 对 commons-logging 依赖，添加 logback 模块。

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23


<dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-core</artifactId>
    <version>${spring.version}</version>
    <exclusions>
        <exclusion>
            <groupId>commons-logging</groupId>
            <artifactId>commons-logging</artifactId>
        </exclusion>
    </exclusions>
</dependency>

<dependency>
	<groupId>ch.qos.logback</groupId>
	<artifactId>logback-classic</artifactId>
	<version>${logback.version}</version>
</dependency>

<dependency>
	<groupId>org.slf4j</groupId>
	<artifactId>jcl-over-slf4j</artifactId>
	<version>1${jcloverslf4j.version}</version>
</dependency>

基本参考配置

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60


<?xml version="1.0" encoding="UTF-8"?>
<configuration>
    <appender name="consoleAppender" class="ch.qos.logback.core.ConsoleAppender">
        <encoder>
            <Pattern>.%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg %n
            </Pattern>
        </encoder>
        <filter class="ch.qos.logback.classic.filter.ThresholdFilter">
            <level>TRACE</level>
        </filter>
    </appender>

    <appender name="dailyRollingFileAppender" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <File>/tmp/spring-demo.log</File>
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <!-- daily rollover -->
            <FileNamePattern>spring-demo.%d{yyyy-MM-dd}.log</FileNamePattern>

            <!-- keep 30 days' worth of history -->
            <maxHistory>30</maxHistory>
        </rollingPolicy>

        <encoder>
            <Pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{35} - %msg %n</Pattern>
        </encoder>
    </appender>

    <appender name="errorFileAppender" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <filter class="ch.qos.logback.classic.filter.LevelFilter">
            <level>ERROR</level>
            <OnMismatch>DENY</OnMismatch>
            <OnMatch>ACCEPT</OnMatch>
        </filter>

        <File>/tmp/spring-err.log</File>
        <rollingPolicy class="ch.qos.logback.core.rolling.FixedWindowRollingPolicy">
            <FileNamePattern>spring-err.log.%i.bak</FileNamePattern>
            <MinIndex>1</MinIndex>
            <MaxIndex>3</MaxIndex>
        </rollingPolicy>
        <triggeringPolicy class="ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy">
            <MaxFileSize>100MB</MaxFileSize>
        </triggeringPolicy>
        <layout class="ch.qos.logback.classic.PatternLayout">
            <Pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</Pattern>
        </layout>
    </appender>

    <logger name="com.EXAMPLE" additivity="false">
        <level value="DEBUG" />
        <appender-ref ref="dailyRollingFileAppender"/>
        <appender-ref ref="errorFileAppender"/>
        <appender-ref ref="consoleAppender" />
    </logger>

    <root>
        <level value="INFO" />
        <appender-ref ref="consoleAppender" />
    </root>
</configuration>

logback 将记录日志任务委托给 appender，有几种不同的日志级别 TRACE, DEBUG, INFO, WARN, ERROR 。

static final Logger logger = LoggerFactory.getLogger(MyClassName.class);

参考

http://www.codingpedia.org/ama/how-to-log-in-spring-with-slf4j-and-logback/

http://logback.qos.ch/documentation.html

文章目录