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

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.

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>
...

Spring boot using slf4j no log file created

I have a spring boot application with trying to use slf4j by following tutorial from https://www.baeldung.com/spring-boot-logging however logs are getting printed only on console side. There is no log file created in given directory /var/logs.
log4j2-spring.xml
<?xml version="1.0" encoding="UTF-8"?>
<Configuration>
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout
pattern="%style{%d{ISO8601}}{black} %highlight{%-5level }[%style{%t}{bright,blue}] %style{%C{1.}}{bright,yellow}: %msg%n%throwable" />
</Console>
<RollingFile name="RollingFile"
fileName="/var/logs/spring-boot-logger-log4j2.log"
filePattern="/var/logs/$${date:yyyy-MM}/spring-boot-logger-log4j2-%d{-dd-MMMM-yyyy}-%i.log.gz">
<PatternLayout>
<pattern>%d %p %C{1.} [%t] %m%n</pattern>
</PatternLayout>
<Policies>
<!-- rollover on startup, daily and when the file reaches
10 MegaBytes -->
<OnStartupTriggeringPolicy />
<SizeBasedTriggeringPolicy
size="10 MB" />
<TimeBasedTriggeringPolicy />
</Policies>
</RollingFile>
</Appenders>
<Loggers>
<!-- LOG everything at INFO level -->
<Root level="info">
<AppenderRef ref="Console" />
<AppenderRef ref="RollingFile" />
</Root>
<Logger name="com.buraktas">
<AppenderRef ref="LogFile"/>
<AppenderRef ref="Console"/>
</Logger>
</Loggers>
</Configuration>
maven dependencies
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>2.1.0.RELEASE</version>
<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>

You can define log path in the application.properties file, check the link below for example:
logging.level.com.example.springscheduler = debug
logging.level.org.springframework.web = WARN
logging.file.name =log/loggingdemocontroller.log
https://springbootmvc.blogspot.com/2020/06/spring-boot-logging-using-orgslf4jlogger.html

I found the problem where I had spring-boot-starter and spring-boot-starter-web dependencies. I excluded spring-boot-starter-logging dependency from only one of them which forced spring to use logback logger. And since logback logger doesn't pick up log4j2.xml for its configuration no files we getting created. So the pom.xml file was something like this;
<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter</artifactId>
<version>2.1.0.RELEASE</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework.boot/spring-boot-starter-web -->
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>2.1.0.RELEASE</version>
<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>
I needed to exclude spring-boot-starter-logging from spring-boot-starter dependency as well. Well, after all since I have spring-boot-starter-web I just deleted spring-boot-starter package which was needless.

Logback Kafka Appender Not Writing Logs to Topic

I am trying to do a simple test of Logback Kafka Appender. Following is what I have in my logback.xml which I have placed in src/main/resources:
<?xml version="1.0" encoding="UTF-8"?>
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<encoder> <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n</pattern>
</encoder>
</appender>
<!-- This is the kafkaAppender -->
<appender name="kafkaAppender"
class="com.github.danielwegener.logback.kafka.KafkaAppender">
<encoder>
<pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
</pattern>
</encoder>
<topic>test</topic>
<keyingStrategy
class="com.github.danielwegener.logback.kafka.keying.NoKeyKeyingStrategy" />
<deliveryStrategy
class="com.github.danielwegener.logback.kafka.delivery.AsynchronousDeliveryStrategy" />
<!-- Optional parameter to use a fixed partition -->
<!-- <partition>0</partition> -->
<!-- Optional parameter to include log timestamps into the kafka message -->
<!-- <appendTimestamp>true</appendTimestamp> -->
<!-- each <producerConfig> translates to regular kafka-client config (format:
key=value) -->
<!-- producer configs are documented here: https://kafka.apache.org/documentation.html#newproducerconfigs -->
<!-- bootstrap.servers is the only mandatory producerConfig -->
<producerConfig>bootstrap.servers=localhost:9092</producerConfig>
<!-- this is the fallback appender if kafka is not available. -->
<!-- <appender-ref ref="STDOUT" /> -->
</appender>
<logger name="com.my.package" level="info" additivity="false">
<appender-ref ref="kafkaAppender" />
</logger>
<root level="info">
<appender-ref ref="kafkaAppender" />
</root>
I have started a Kafka server on Windows with a separate Zookeeper. I have created a test topic as well.
Started Zookeeper on Windows with : zkServer.cmd
Started Kafka Server on Windows with : kafka-server-start.bat config\server.properties
Created a topic : kafka-topics.bat --create --zookeeper localhost:2181 --replication-factor 1 --partitions 1 --topic test
Started a consumer on Windows with : kafka-console-consumer.bat --bootstrap-server localhost:9092 --topic test --from-beginning
In my Java class all I have is a logger inside a method.
private static final Logger logger =
LoggerFactory.getLogger(FormController.class);
logger.debug("DEBUG :: Inside do post method");
logger.info("INFO :: Inside do post method");
My imports are:
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
My pom.xml is as follows:
<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.my.package</groupId>
<artifactId>SampleIGApp</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>SampleIGApp Maven Webapp</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>javax.servlet-api</artifactId>
<version>3.1.0</version>
<scope>provided</scope>
</dependency>
<!-- https://mvnrepository.com/artifact/log4j/log4j -->
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-api -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.21</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.slf4j/slf4j-simple -->
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-simple</artifactId>
<version>1.7.21</version>
</dependency>
<!-- https://mvnrepository.com/artifact/org.apache.kafka/kafka-clients -->
<dependency>
<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
<version>1.0.1</version>
</dependency>
<!-- https://mvnrepository.com/artifact/com.github.danielwegener/logback-kafka-appender -->
<dependency>
<groupId>com.github.danielwegener</groupId>
<artifactId>logback-kafka-appender</artifactId>
<version>0.2.0-RC1</version>
</dependency>
</dependencies>
<build>
<finalName>MyApp</finalName>
</build>
Can someone please tell me as to what am I doing wrong? Even if I comment out STDOUT appender-name, then also logs keep getting written to console, which in my case is Tomcat's catalina.out. I would appreciate any help. Thank you.

The documentation says you need to add logback-classic as dependency:
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.2.3</version>
<scope>runtime</scope>
</dependency>
logback-kafka-appender

Spring - SpringJUnit4ClassRunner still using LOG4J 1 instead of 2?

I am using the SpringRunner class to guide my IT tests:
#ContextConfiguration(loader = AnnotationConfigContextLoader.class, classes = MyTestConfiguration.class)
#RunWith(SpringRunner.class)
class SomeTestIT {
// tests here
}
#Configuration
public class MyTestConfiguration {
}
I have the following Maven dependencies for log4j2:
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-bom</artifactId>
<version>2.9.1</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<dependencies>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-api</artifactId>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>5.0.1.RELEASE</version>
<scope>test</scope>
</dependency>
My log4j2.xml looks as following:
<?xml version="1.0" encoding="UTF-8"?>
<Configuration strict="true" monitorInterval="30" status="error">
<Appenders>
<Console name="Console" target="SYSTEM_OUT">
<PatternLayout pattern="%5p | %d | %F | %L | %m%n"/>
</Console>
</Appenders>
<Loggers>
<Root level="error">
<AppenderRef ref="Console"/>
</Root>
</Loggers>
</Configuration>
I have put this log4j2.xml in src/test/resources.
Now, when the tests are running, I get the following warnings:
log4j:WARN No appenders could be found for logger (org.springframework.test.context.junit4.SpringJUnit4ClassRunner).
log4j:WARN Please initialize the log4j system properly.
log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.
For some reason I cannot find, my log4j2 configuration is not being used for loggings from SpringRunner. How can I debug and hopefully fix this?
update
I do not think it is related, but just in case: I have also following dependencies:
<dependencies>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.25</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.25</version>
</dependency>

This is old log4j binding:
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-log4j12</artifactId>
<version>1.7.25</version>
</dependency>
Here slf4j-log4j12 states for slf4j over log4j v1.2
You should update your slf4j binding to
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-slf4j-impl</artifactId>
<version>2.9.1</version>
</dependency>
Latest version is 2.9.1. Version earlier than 2.9.0 doesn't match your SLF4J API version.

SLF4J and Log4j 2 binding Maven dependency

Hopefully a simple question but My google foo is failing me - I've got a maven project where we're using SLF4J with Log4J 1.2 bindings.
We now want to move to Log4j 2 particularly for the performance improvement - however, I can't for the life of me find the maven dependency for the log4j 2.0 binding. I've found some notes at http://logging.apache.org/log4j/2.x/log4j-slf4j-impl/ but no mention of any dependency info.
I'm also slightly confused by the fact there's apparently two ways to put slf4j on top of log4j2 (binding or adaptor)
What's the correct way to bind slf4j with log4j2 and how do I define the maven dependencies?
Editing to add some code following the 1st answer below, I'm getting exception:
Exception in thread "main" java.lang.NoSuchMethodError:
org/apache/logging/log4j/spi/AbstractLoggerWrapper.(Lorg/apache/logging/log4j/spi/AbstractLogger;Ljava/lang/String;)V
at org.slf4j.impl.SLF4JLogger.(SLF4JLogger.java:48)
POM:
<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>logging.test</groupId>
<artifactId>logtest2</artifactId>
<version>0.0.1</version>
<name>logtest2</name>
<description>logtest2</description>
<build>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.1</version>
<configuration>
<source>1.6</source>
<target>1.6</target>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j.adapters</groupId>
<artifactId>log4j-slf4j-impl</artifactId>
<version>2.0-beta3</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>2.0-beta9</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-api</artifactId>
<version>2.0-beta9</version>
</dependency>
</dependencies>
My log4j.xml:
<?xml version="1.0" encoding="UTF-8"?> <!DOCTYPE log4j:configuration PUBLIC "-//APACHE//DTD LOG4J 1.2//EN" "log4j.dtd"> <log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
<appender name="A1" class="org.apache.log4j.FileAppender">
<param name="File" value="c:/logtest2.0/log.txt" />
<param name="Append" value="false" />
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d %p %X{sessionId} %c MSG: %m%n" />
</layout>
</appender>
<appender name="STDOUT" class="org.apache.log4j.ConsoleAppender">
<layout class="org.apache.log4j.PatternLayout">
<param name="ConversionPattern" value="%d %p %X{sessionId} %c MSG: %m%n" />
</layout>
</appender>
<category name="org.apache.log4j.xml">
<priority value="debug" />
<appender-ref ref="A1" />
</category>
<root>
<priority value="debug" />
<appender-ref ref="STDOUT" />
</Root> </log4j:configuration>
and my test java class:
package loggertest;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
public class LoggerTest {
public static final Logger LOGGER = LoggerFactory.getLogger(LoggerTest.class);
public static void main(final String[] p_args) throws InterruptedException {
LOGGER.debug("Logger test");
}
}

"org.apache.logging.log4j:log4j-slf4j-impl:2.0-beta9" -
LOG4J implementation of SLF4J API
"org.apache.logging.log4j:log4j-core:2.0-beta9" - Core LOG4J implementation
This, plus a valid log4j2.xml on the classpath should get you started.

If you like to divert jars that use commons logging, log4j1 and others as well redirected to slf4j and finally use log4j2 implementation for logging.. here is the set that need to be used...
Explanation: First two are excluding the log4j1 and commons-logging not there in classpath. log4j-over-slf4j and jcl-over-slf4j provide proxies that redirect to slf4j api. Remaining are log4j2 implementation dependencies.
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
<version>1.2</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>log4j</groupId>
<artifactId>log4j</artifactId>
<version>1.2.17</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>log4j-over-slf4j</artifactId>
<version>1.7.7</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.7</version>
</dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>jcl-over-slf4j</artifactId>
<version>1.7.7</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-core</artifactId>
<version>2.17.1</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-slf4j-impl</artifactId>
<version>2.17.1</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-api</artifactId>
<version>2.17.1</version>
</dependency>
<dependency>
<groupId>org.apache.logging.log4j</groupId>
<artifactId>log4j-layout-template-json</artifactId>
<version>2.17.1</version>
</dependency>