SpringBoot日志

工程结构：

默认使用logback日志

pom

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.example</groupId>
    <artifactId>boot-logging</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>boot-logging</name>
    <description>Demo project for Spring Boot</description>

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
        <java.version>1.8</java.version>
    </properties>

    <dependencies>
        <!-- 使用logback日志时取消注释
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>-->

        <!--使用log4j2-->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-logging</artifactId>
                </exclusion>
            </exclusions>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-log4j2</artifactId>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>


</project>

在application.properties中可以直接配置

# 设置日志级别（默认是info）
#logging.level.com.example.bootlogging.b.TestLogger1 = debug
#logging.level.com.example.bootlogging.a.TestLogger = debug
## 设置日志文件的名称及路径
## logging.file=d:/logs/my.log
## 设置日志文件存储的位置
#logging.path=d:/tmp/logs
## 设置控制台输出格式
#logging.pattern.console=%d{HH:mm:ss.SSS} [boot-logging] [%t] %-5level %logger{36} - %msg%n
## 设置文件的输出格式
#logging.pattern.file= %d{HH:mm:ss.SSS} [boot-logging] [%t] %-5level %logger{36} - %msg%n

还可以使用XML配置，名字是固定的logback-spring.xml

<?xml version="1.0" encoding="UTF-8"?>
<configuration debug="false">
    <!--定义日志文件的存储地址 勿在 LogBack 的配置中使用相对路径-->
    <property name="LOG_HOME" value="/home"/>
    <!-- 控制台输出 -->
    <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <!--格式化输出：%d表示日期，%thread表示线程名，%-5level：级别从左显示5个字符宽度%msg：日志消息，%n是换行符-->
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%n</pattern>
        </encoder>
    </appender>
    <!-- 按照每天生成日志文件 -->
    <appender name="FILE" class="ch.qos.logback.core.rolling.RollingFileAppender">
        <rollingPolicy class="ch.qos.logback.core.rolling.TimeBasedRollingPolicy">
            <!--日志文件输出的文件名-->
            <FileNamePattern>${LOG_HOME}/TestWeb.log.%d{yyyy-MM-dd}.log</FileNamePattern>
            <!--日志文件保留天数-->
            <MaxHistory>30</MaxHistory>
        </rollingPolicy>
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <!--格式化输出：%d表示日期，%thread表示线程名，%-5level：级别从左显示5个字符宽度%msg：日志消息，%n是换行符-->
            <pattern>%d{yyyy-MM-dd HH:mm:ss.SSS} [%thread] %-5level %logger{50} - %msg%n</pattern>
        </encoder>
        <!--日志文件最大的大小-->
        <triggeringPolicy class="ch.qos.logback.core.rolling.SizeBasedTriggeringPolicy">
            <MaxFileSize>10MB</MaxFileSize>
        </triggeringPolicy>
    </appender>

    <!-- 日志输出级别 -->
    <root level="INFO">
        <appender-ref ref="STDOUT"/>
    </root>
</configuration>

如果使用log4j2

建立log4j2-spring.xml文件

<?xml version="1.0" encoding="UTF-8"?>
<!-- 设置log4j2的自身log级别为warn -->
<!-- OFF > FATAL > ERROR > WARN > INFO > DEBUG > TRACE > ALL -->
<configuration status="WARN" monitorInterval="30">
    <appenders>
        <console name="Console" target="SYSTEM_OUT">
            <PatternLayout pattern="[%d{HH:mm:ss:SSS}] [%p] - %l - %m%n"/>
        </console>
    </appenders>

    <loggers>
        <root level="all">
            <appender-ref ref="Console"/>
        </root>
    </loggers>
</configuration>

package com.example.bootlogging.a;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

@Component
public class TestLogger {

    // 获取日志对象
    private Logger logger = LoggerFactory.getLogger(TestLogger.class);

    public void testLog() {
        logger.warn("警告日志");
        logger.info("信息日志");
        logger.debug("调试日志");
        logger.error("错误日志");
    }
}

package com.example.bootlogging.b;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.stereotype.Component;

@Component
public class TestLogger1 {

    // 获取日志对象
    private Logger logger = LoggerFactory.getLogger(TestLogger1.class);

    public void testLog() {
        logger.warn("警告日志-b");
        logger.info("信息日志-b");
        logger.debug("调试日志-b");
        logger.error("错误日志-b");
    }
}

测试类：

package com.example.bootlogging;

import com.example.bootlogging.a.TestLogger;
import com.example.bootlogging.b.TestLogger1;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ConfigurableApplicationContext;

@SpringBootApplication
public class BootLoggingApplication {

    public static void main(String[] args) {
        ConfigurableApplicationContext
                context = SpringApplication.run(BootLoggingApplication.class, args);
        TestLogger logger = context.getBean(TestLogger.class);
        logger.testLog();

        TestLogger1 logger1 = context.getBean(TestLogger1.class);
        logger1.testLog();

        context.close();
    }
}

输出结果：（log4j2）