How to Create Java+Spring Based executable .jar with all Required Dependencies, Properties and Resources?

Last week I wrote a tutorial on how to use maven-resources-plugin, maven-dependency-plugin & maven-jar-plugin to generate your complete executable Jar Project? As a result it creates / copies all required files to /target/Crunchify folder.

But what if you just need to bundle everything from your Java Project into just one file? Let’s say Crunchify.jar (with all files inside).  A few days ago I was looking for the same, a way to create a runnable binary distribution of a standalone Java application by using Maven. In other words:

1. How to create spring-based executable jar with maven?
2. Creating a Runnable Binary Distribution With Maven for Java + Spring + Other dependencies
3. How to Build Java + Spring Projects with Maven?

Normally in Maven, we relies on dependency management. An artifact just contains the classes/resources of itself. Maven will be responsible to find out all artifacts (JARs etc) that the project is dependent, when compiling and for running etc.

With the help of maven-shade-plugin I was able to achieve this goal. It provides the capability to package the artifact in an uber-jar, including its dependencies and to shade - i.e. rename – the packages of some of the dependencies.

In my project I’ve so many other dependencies, i.e. Spring Framework, JSON, 3rd Party tools, etc. Below is just a sample project but my production .jar file came out to ~120MB big.

Here is a end result.

An uber-jar is something that take all dependencies, and extract the content of the dependencies and put it in the one JAR, with the classes/resources of the project itself. By having such uber-jar, it is easy for execution, because you will need only one big JAR instead of tons of small JARs to run your app. It also ease the distribution in some case.

Let’s take a look at complete pom.xml file. Mainly lines 96-130.

<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>CrunchifyMavenBuildPlugins</groupId>
	<artifactId>CrunchifyMavenBuildPlugins</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>CrunchifyMavenBuildPlugins</name>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
	</properties>

	<dependencies>
		<dependency>
			<groupId>log4j</groupId>
			<artifactId>log4j</artifactId>
			<version>1.2.17</version>
		</dependency>
		<dependency>
			<groupId>com.googlecode.json-simple</groupId>
			<artifactId>json-simple</artifactId>
			<version>1.1</version>
		</dependency>
		<dependency>
			<groupId>axis</groupId>
			<artifactId>axis</artifactId>
			<version>1.4</version>
		</dependency>
		<dependency>
			<groupId>commons-beanutils</groupId>
			<artifactId>commons-beanutils</artifactId>
			<version>1.8.3</version>
		</dependency>
		<dependency>
			<groupId>commons-collections</groupId>
			<artifactId>commons-collections</artifactId>
			<version>3.2.1</version>
		</dependency>
		<dependency>
			<groupId>commons-configuration</groupId>
			<artifactId>commons-configuration</artifactId>
			<version>1.10</version>
		</dependency>
		<dependency>
			<groupId>commons-io</groupId>
			<artifactId>commons-io</artifactId>
			<version>2.4</version>
		</dependency>
		<dependency>
			<groupId>javax.mail</groupId>
			<artifactId>mail</artifactId>
			<version>1.4.7</version>
		</dependency>
		<dependency>
			<groupId>javax.servlet</groupId>
			<artifactId>servlet-api</artifactId>
			<version>2.5</version>
		</dependency>
		<dependency>
			<groupId>org.json</groupId>
			<artifactId>json</artifactId>
			<version>20140107</version>
		</dependency>
		<dependency>
			<groupId>axis</groupId>
			<artifactId>axis-saaj</artifactId>
			<version>1.4</version>
		</dependency>
		<dependency>
			<groupId>wsdl4j</groupId>
			<artifactId>wsdl4j</artifactId>
			<version>1.6.3</version>
		</dependency>
		<dependency>
			<groupId>com.google.zxing</groupId>
			<artifactId>core</artifactId>
			<version>2.0</version>
		</dependency>
	</dependencies>

	<build>
		<pluginManagement>
			<plugins>
				<plugin>
					<groupId>org.apache.maven.plugins</groupId>
					<artifactId>maven-compiler-plugin</artifactId>
					<version>2.3.1</version>
					<configuration>
						<source>1.7</source>
						<target>1.7</target>
					</configuration>
				</plugin>
			</plugins>
		</pluginManagement>
		<plugins>
			<plugin>
				<groupId>org.apache.maven.plugins</groupId>
				<artifactId>maven-shade-plugin</artifactId>
				<version>1.7</version>
				<executions>
					<execution>
						<phase>package</phase>
						<goals>
							<goal>shade</goal>
						</goals>
						<configuration>
							<!-- Optional Start -->
							<finalName>Crunchify</finalName>
							<shadedArtifactAttached>true</shadedArtifactAttached>
							<shadedClassifierName>jar-with-dependencies</shadedClassifierName>
							<!-- Optional End -->
							
							<transformers>
								<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
									<mainClass>com.crunchify.tutorial.CrunchifyMain</mainClass>
								</transformer>
								<transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
			     <resource>META-INF/spring.handlers</resource>
								</transformer>
								<transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
									     <resource>META-INF/spring.schemas</resource>
								</transformer>
								<transformer implementation="org.apache.maven.plugins.shade.resource.AppendingTransformer">
			     <resource>META-INF/spring.tooling</resource>
								</transformer>
							</transformers>
						</configuration>
					</execution>
				</executions>
			</plugin>

		</plugins>
	</build>
</project>

As you can see here I’m using Resource Transformers in pom.xml file. Aggregating classes/resources from several artifacts into one uber JAR is straight forward as long as there is no overlap. Otherwise, some kind of logic to merge resources from several JARs is required. This is where resource transformers kick in.

Once you add maven-shade-plugin to your pom.xml file then just use below command to build your project.

mvn clean install

And you should see one Crunchify.jar file created with all dependencies mentioned in pom.xml file inside.

Do you have anything to add? Add it to comment section below. Enjoy, Have a great day ahead and Happy Coding.

The post How to Create Java+Spring Based executable .jar with all Required Dependencies, Properties and Resources? appeared first on Crunchify.
Author: Arpit Shah