How to make log4j2 create different logging files with Spring Boot and Maven

Question

I am a beginner and have a problem with setting log4j2 in my Spring Boot application. I've tried to do it myself for about a week now, read many hints, posts and tutorials and still didn't find solution. Could anyone pls help me with that? I would like to create different files for different log levels like error.log, warn.log and so on.

pom.xml

<?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>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.1.6.RELEASE</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.assessment.ww</groupId>
    <artifactId>Assessment_Exercise</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>Assessment_Exercise</name>
    <description>Spring Boot Project</description>

    <properties>
        <java.version>1.8</java.version>
    </properties>

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

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

        <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-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <scope>runtime</scope>
        </dependency>

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

log4j2.xml

<?xml version="1.0" encoding="UTF-8"?>
<Configuration status="WARN">
    <Appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{yyyy-MMM-dd HH:mm:ss} [%t] %-5level %logger{36} - %msg%n"/>
        </Console>

        <File name="File" target="logs/app.log">
            <PatternLayout pattern="%d{yyyy-MMM-dd HH:mm:ss} [%t] %-5level %logger{36} - %msg%n"/>
        </File>
    </Appenders>

    <Loggers>
<!--        Log everything -->
        <Logger name="com.assessment.ww.Assessment_Exercise" level="debug" additivity="false">
            <AppenderRef ref="Console"/>
            <AppenderRef ref="File"/>
        </Logger>

<!--        Log everything in Spring Boot -->
        <Logger name="org.springframework.boot" level="debug" additivity="false">
            <AppenderRef ref="Console"/>
            <AppenderRef ref="File"/>
        </Logger>

<!--        Log everything in Spring Core -->
        <Logger name="org.springframework.core" level="debug" additivity="false">
            <AppenderRef ref="Console"/>
            <AppenderRef ref="File"/>
        </Logger>

        <Root level="all">
            <AppenderRef ref="Console"/>
            <AppenderRef ref="File"/>
        </Root>
    </Loggers>
</Configuration>

starting class

package com.assessment.ww.Assessment_Exercise;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;

@SpringBootApplication
public class AssessmentExerciseApplication {

    private static final Logger logger = LogManager.getLogger(AssessmentExerciseApplication.class);

    public static void main(String[] args) {

        SpringApplication.run(AssessmentExerciseApplication.class, args);

        logger.info("Starting SB app");
    }
}

I also have such a warning - maybe it will help: enter image description here

It prints my logger.info message (but why without formatting?) but do not create any files. enter image description here

Thank You in advance for any advices.

Answer 1

Finally, I've found a solution. The problem was Logback - even that I disabled it in spring-boot-starter-web dependency in pom.xml, it was still active in spring-boot-starter-data-jpa and spring-boot-starter-actuator. So now my pom.xml looks like this:

...
<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-actuator</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-data-jpa</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-web</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-logging</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
...