Create runnable jar in java using apache shade plugin (maven/example)

What we will have in this post ?

• We will create a maven project and add apache shade plug-in.
  • Create runnable JAR using shade plug-in.
• Create a class having main method.
• Log information using Log4J logging framework.

Program – create runnable jar using apache shade plugin

• Create a class containing main method.
  • We will register main method in shade plugin configuration (refer pom file)
• Log execution information using logger framework.

package org.learn.application;

import java.util.Arrays;
import java.util.List;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class Application {
 private static final Logger logger = LoggerFactory.getLogger(Application.class);

 public static void main(String[] args) {
  logger.info("Starting execution of main method!");
  logger.info("Printing sports list:");
  List<String> listOfSports = Arrays.asList("Soccer", "Badminton", "Tennis", "Rugby", "BaseBall");
  listOfSports.stream().forEach((sport) -> {
   logger.info(sport);

  });
  logger.info("Completed the execution of main method");
 }
}

Maven dependencies (POM) of shade plugin & logger framework

• Added log4j dependencies.
• Added class having main method in mainClass tag (Refer following pom file).
  • <mainClass>org.learn.application.Application</mainClass>

<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>org.learn</groupId>
 <artifactId>mavenShadeRunnableJar</artifactId>
 <version>1.0</version>
 <packaging>jar</packaging>
 <name>mavenShadeRunnableJar</name>
 <url>http://maven.apache.org</url>
 <properties>
  <java_compiler_version>1.8</java_compiler_version>
  <maven_compiler_version>3.5.1</maven_compiler_version>
  <shade_plugin_version>2.4.3</shade_plugin_version>
  <slf_version>1.7.2</slf_version>
 </properties>
 <dependencies>
  <dependency>
   <groupId>org.slf4j</groupId>
   <artifactId>slf4j-api</artifactId>
   <version>${slf_version}</version>
  </dependency>
  <dependency>
   <groupId>org.slf4j</groupId>
   <artifactId>slf4j-log4j12</artifactId>
   <version>${slf_version}</version>
  </dependency>
  <dependency>
   <groupId>junit</groupId>
   <artifactId>junit</artifactId>
   <version>3.8.1</version>
   <scope>test</scope>
  </dependency>
 </dependencies>
 <build>  
  <plugins>
   <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-compiler-plugin</artifactId>
    <version>${maven_compiler_version}</version>
    <configuration>
     <source>${java_compiler_version}</source>
     <target>${java_compiler_version}</target>
    </configuration>
   </plugin>
   <plugin>
    <groupId>org.apache.maven.plugins</groupId>
    <artifactId>maven-shade-plugin</artifactId>
    <version>${shade_plugin_version}</version>
    <executions>
     <execution>
      <phase>package</phase>
      <goals>
       <goal>shade</goal>
      </goals>
      <configuration>
       <shadedArtifactAttached>true</shadedArtifactAttached>
       <shadedClassifierName>jar-with-dependencies</shadedClassifierName>

       <transformers>
        <transformer
         implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
         <mainClass>org.learn.application.Application</mainClass>
        </transformer>
       </transformers>
      </configuration>
     </execution>
    </executions>
   </plugin>
  </plugins>
 </build>
</project>

Example of Log4J.properties is:

log4j.rootLogger=INFO,stdout
log4j.logger.org.learn=INFO

log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%d{ISO8601}\t[%p] %c [%t] %m%n

Execute runnable jar containing all dependencies

• We will execute runnable jar in windows os.
• Build project using maven clean install command.
• Go to the target directory, where we will get output mavenShadeRunnableJar-1.0-jar-with-dependencies.jar
• Execute command java -jar mavenShadeRunnableJar-1.0-jar-with-dependencies.jar
  • Go to target directory and execute above command.
• Once we successfully executed the jar, we will get following output

2016-07-03 21:48:22,130 [INFO] org.learn.application.Application [main] Starting execution of main method!
2016-07-03 21:48:22,131 [INFO] org.learn.application.Application [main] Printing sports list:
2016-07-03 21:48:22,217 [INFO] org.learn.application.Application [main] Soccer
2016-07-03 21:48:22,218 [INFO] org.learn.application.Application [main] Badminton
2016-07-03 21:48:22,218 [INFO] org.learn.application.Application [main] Tennis
2016-07-03 21:48:22,218 [INFO] org.learn.application.Application [main] Rugby
2016-07-03 21:48:22,218 [INFO] org.learn.application.Application [main] BaseBall
2016-07-03 21:48:22,218 [INFO] org.learn.application.Application [main] Completed the execution of main method

Download code – create runnable Jar (apache shade Plugin)