I have the following dependencies in my build.gradle file.
compile 'org.slf4j:slf4j-api:1.7.25'
compile group: 'org.apache.logging.log4j', name: 'log4j-core', version: '2.11.1'
compile group: 'org.apache.logging.log4j', name: 'log4j-api', version: '2.11.1'
On running my unit tests, the following logs are displayed.
exclude patterns:SLF4J: Class path contains multiple SLF4J bindings.
SLF4J: Found binding in
[jar:file:....gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-slf4j-impl/2.7/382b070836b8940a02d28c936974db95e9bfc3a4/log4j-slf4j-impl-2.7.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: Found binding in [jar:file:/Users/z002qz1/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-slf4j-impl/2.9.1/a97a849b18b3798c4af1a2ca5b10c66cef17e3a/log4j-slf4j-impl-2.9.1.jar!/org/slf4j/impl/StaticLoggerBinder.class]
SLF4J: See for an explanation.
SLF4J: Actual binding is of type [org.apache.logging.slf4j.Log4jLoggerFactory]
java.lang.NoClassDefFoundError: org/apache/logging/log4j/util/ReflectionUtil
at org.apache.logging.slf4j.Log4jLoggerFactory.getContext(Log4jLoggerFactory.java:42)
at org.apache.logging.log4j.spi.AbstractLoggerAdapter.getLogger(AbstractLoggerAdapter.java:46)
at org.apache.logging.slf4j.Log4jLoggerFactory.getLogger(Log4jLoggerFactory.java:29)
at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:358)
I'm using springboot 2.0.4.RELEASE. I'm hoping this is just some sort of version mismatch issue. Any insights are appreciated.
2 Answers
The error: java.lang.NoClassDefFoundError: org/apache/logging/log4j/util/ReflectionUtil
is because log4j2 since version 2.9.0 has been removed that class from api jar (log4j-api-2.x.x.jar).
The last version that has it, is 2.8.2
Probably you have mixed versions in the classpath.
Correct way to configure log4j2 in spring boot is like this:
dependencies {
compile 'org.springframework.boot:spring-boot-starter-web'
compile 'org.springframework.boot:spring-boot-starter-log4j2'
}
configurations {
all {
exclude group: 'org.springframework.boot', module: 'spring-boot-starter-logging'
}
}
