Spring Boot 不加载 log4j2.xml

Question

I'm trying to add log4j2 framework inside my spring boot application, and I'm using spring AOP to isolate logging concern apart from my logic business. Unfortunately when I try to log my messages, log4j2 doesn't work and it uses the spring default logging instead.

This is my Logging aspect class where I try to log messages: LoggingAspect.java

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.Around;
import org.aspectj.lang.annotation.Aspect;
import org.springframework.stereotype.Component;
import org.springframework.util.StopWatch;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

@Aspect
@Component
public class LoggingAspect {
    @Around("com.obs.dqsc.api.config.AspectConfig.businessService() || com.obs.dqsc.api.config.AspectConfig.repositoryOperations()")
    public Object logMethod(final ProceedingJoinPoint joinPoint)
            throws Throwable {
        final Class<?> targetClass = joinPoint.getTarget().getClass();
        final Logger logger = LoggerFactory.getLogger(targetClass);

        try {
            final String className = targetClass.getSimpleName();
            logger.debug(getPreMessage(joinPoint, className));

            final StopWatch stopWatch = new StopWatch();
            stopWatch.start();

            final Object retVal = joinPoint.proceed();
            stopWatch.stop();

            logger.debug(getPostMessage(joinPoint, className, stopWatch.getTotalTimeMillis()));

            return retVal;
        } catch (final Throwable ex) {
            logger.error(getErrorMessage(ex), ex);
            throw ex;
        }
    }

    private static String getPreMessage(final JoinPoint joinPoint, final String className) {
        final StringBuilder builder = new StringBuilder()
                .append("Entered in ").append(className).append(".")
                .append(joinPoint.getSignature().getName())
                .append("(");
        appendTo(builder, joinPoint);
        return builder
                .append(")")
                .toString();
    }

    private static String getPostMessage(final JoinPoint joinPoint, final String className, final long millis) {
        return "Exit from " + className + "." +
                joinPoint.getSignature().getName() +
                "(..); Execution time: " +
                millis +
                " ms;";
    }

    private static String getErrorMessage(final Throwable ex) {
        return ex.getMessage();
    }

    private static void appendTo(final StringBuilder builder, final JoinPoint joinPoint) {
        final Object[] args = joinPoint.getArgs();
        for (int i = 0; i < args.length; i++) {
            if (i != 0) {
                builder.append(", ");
            }
            builder.append(args[i]);
        }
    }

}

This is my pom.xml file :

<?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>2.5.5</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.obs.dqsc</groupId>
    <artifactId>dqsc-api</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>api</name>
    <description>Demo project for Spring Boot</description>
    <properties>
        <java.version>16</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-mongodb</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-starter-log4j2</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-aop</artifactId>
        </dependency>
        <dependency>
            <groupId>org.aspectj</groupId>
            <artifactId>aspectjweaver</artifactId>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi</artifactId>
            <version>5.0.0</version>
        </dependency>
        <dependency>
            <groupId>org.apache.poi</groupId>
            <artifactId>poi-ooxml</artifactId>
            <version>5.0.0</version>
        </dependency>

    </dependencies>

    <build>
        <finalName>api-0.0.1-SNAPSHOT</finalName>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <version>${project.parent.version}</version>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

Finally this is my log4j2.xml file :

<?xml version="1.0" encoding="UTF-8"?>
<Configuration>
    <Appenders>
        <Console name="Console" target="SYSTEM_OUT">
            <PatternLayout pattern="%d{yyyy-MMM-dd HH:mm:ss} [%t] %-5level %-50c{1.} - %msg%n" />
        </Console>
    </Appenders>

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

And also when I try to use logger.info() instead of logger.debug() it prints something in the console, but with .debug() it does not! (the message was printed using spring default logging apparently)

my application.properties does not contain anything related to log4j, and also my log4j2.xml is inside src/main/resources

Answer 1

exclude spring boot default logging this way:

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

and add spring boot log4j2 dependency like you already do and you´ll be fine. Cause you excluded the logging module only on the web module it still gets pulled in by other dependencies like the data mongodb module for example.