Logging

The client uses SLF4J for logging. It logs useful things, such as exception stack traces when a job handler fails execution. Using the SLF4J API, any SLF4J implementation can be plugged in. The following example uses Log4J 2.

Maven dependencies

<dependency>

<groupId>org.apache.logging.log4j</groupId>

<artifactId>log4j-slf4j-impl</artifactId>

<version>2.8.1</version>

</dependency>

<dependency>

<groupId>org.apache.logging.log4j</groupId>

<artifactId>log4j-core</artifactId>

<version>2.8.1</version>

</dependency>

Configuration

Add a file called log4j2.xml to the classpath of your application. Add the following content:

<?xml version="1.0" encoding="UTF-8"?>

<Configuration status="WARN" strict="true"

xmlns="http://logging.apache.org/log4j/2.0/config"

xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

xsi:schemaLocation="http://logging.apache.org/log4j/2.0/config https://raw.githubusercontent.com/apache/logging-log4j2/log4j-2.8.1/log4j-core/src/main/resources/Log4j-config.xsd">

<Appenders>

<Console name="Console" target="SYSTEM_OUT">

<PatternLayout pattern="%d{HH:mm:ss.SSS} [%t] %-5level Java Client: %logger{36} - %msg%n"/>

</Console>

</Appenders>

<Loggers>

<Root level="info">

<AppenderRef ref="Console"/>

</Root>

</Loggers>

</Configuration>

This will log every log message to the console.