我使用SpringInitializr创建了一个演示程序。
jdk8 maven 3.6.3视窗11
导入
<?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 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.5.10</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<name>demo</name>
<description>demo</description>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-logging</artifactId>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</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>
主应用程序
package com.example.demo;
import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
@Slf4j
public class Application {
public static void main(String[] args) {
log.info("log output before SpringApplication.run");
SpringApplication.run(Application.class, args);
System.out.println("after SpringApplication.run first System.out.println");
log.info("log output after SpringApplication.run");
System.out.println("System.out.println end");
}
}
结果
03:23:26.850 [main] INFO com.example.demo.Application - log output before SpringApplication.run
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.5.10)
after SpringApplication.run first System.out.println
System.out.println end
为什么控制台不输出log.info(),却能输出System.out.println()?我试过改变logback的版本,或者用log4j,都有同样的结果
"非常感谢你的帮助"
1条答案
按热度按时间gwbalxhn1#
这是因为您在
application.properties
文件(或其他记录器配置文件)中将logging level
设置为WARN
或ERROR
。例如,在
application.properties
中默认情况下,它是
INFO
-这就是为什么您在Spring应用程序启动之前看到打印的日志。然后,Spring应用程序启动并将级别更改为以下INFO之一:错误或警告-根据您提供的配置。