Create JAR file as Aggregation in maven multi module package - maven

Question

I have following architecture
Now if i am creating parent child relationship and building child first and parent end it will working fine
<packaging>jar</packaging>
Requirements :
I need packaging with following features :
Command run on parent project "A" - mvn clean install package etc
First create Jar "B" ,"C","D"
then create Jar "A"
then add "B","C","D" jar inside Jar A
When i am adding modules
<modules>
<module>../B</module>
<module>../C</module>
<module>../D</module>
</modules>
then maven force to add
<packaging>pom</packaging>
insted of
<packaging>jar</packaging>
Issue :
When i am adding packaging pom so jar "A" is not crearing
SO i have tried to create one super pom
POM Super :
<packaging>pom</packaging>
<modules>
<module>../A</module>
</modules>
POM A:
<parent>
<groupId>com.khan.vaquar</groupId>
<artifactId>Super</artifactId>
<version>0.0.1-SNAPSHOT</version>
<relativePath/>
</parent>
<packaging>pom</packaging>
<modules>
<module>../B</module>
<module>../C</module>
<module>../D</module>
</modules>
<dependencies>
<!-- B -->
<dependency>
<groupId>com.khan.vaquar</groupId>
<artifactId>B</artifactId>
<version>0.0.1-SNAPSHOT</version>
<scope>compile</scope>
</dependency>
<!-- C -->
<dependency>
<groupId>com.khan.vaquar</groupId>
<artifactId>C</artifactId>
<version>0.0.1-SNAPSHOT</version>
<scope>compile</scope>
</dependency>
<!-- D-->
<dependency>
<groupId>com.khan.vaquar</groupId>
<artifactId>D</artifactId>
<version>0.0.1-SNAPSHOT</version>
<scope>compile</scope>
</dependency>
<!-- Swagger -->
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger2</artifactId>
<version>2.6.1</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>io.springfox</groupId>
<artifactId>springfox-swagger-ui</artifactId>
<version>2.6.1</version>
<scope>compile</scope>
</dependency>
</dependencies>
POM B:
<packaging>jar</packaging>
<parent>
<groupId>com.khan.vaquar</groupId>
<artifactId>A</artifactId>
<version>0.0.1-SNAPSHOT</version>
<relativePath/>
</parent>
POM C:
<packaging>jar</packaging>
<parent>
<groupId>com.khan.vaquar</groupId>
<artifactId>A</artifactId>
<version>0.0.1-SNAPSHOT</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
POM D:
<packaging>jar</packaging>
<parent>
<groupId>com.khan.vaquar</groupId>
<artifactId>A</artifactId>
<version>0.0.1-SNAPSHOT</version>
<relativePath/>
</parent>
Problem : maven not allow to add jar if we are adding module , so how can i add child jar into parent jar and create build .

Answer 1

To create fat jar from multiple modules you can use maven-shade-plugin in A project
as
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.4.3</version>
<executions>
<execution>
<id>create-fat-jar</id>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<transformers>
<!-- add Main-Class to manifest file -->
<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>com.nk.test.Application</mainClass>
</transformer>
</transformers>
<finalName>A</finalName>
</configuration>
</execution>
</executions>
</plugin>
For your example you can create structure as
parent module
<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>com.nk.test</groupId>
<artifactId>P</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>pom</packaging>
<modules>
<module>../C</module>
<module>../B</module>
<module>../A</module>
</modules>
</project>
Core project A with maven-shade-plugin and project B & C as dependencies
<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>com.nk.test</groupId>
<artifactId>A</artifactId>
<version>0.0.1-SNAPSHOT</version>
<dependencies>
<dependency>
<artifactId>B</artifactId>
<version>0.0.1-SNAPSHOT</version>
<groupId>com.nk.test</groupId>
</dependency>
<dependency>
<artifactId>C</artifactId>
<version>0.0.1-SNAPSHOT</version>
<groupId>com.nk.test</groupId>
</dependency>
</dependencies>
<build>
<plugins>
**<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-shade-plugin</artifactId>
<version>2.4.3</version>
<executions>
<execution>
<id>create-fat-jar</id>
<phase>package</phase>
<goals>
<goal>shade</goal>
</goals>
<configuration>
<transformers>
<!-- add Main-Class to manifest file -->
<transformer implementation="org.apache.maven.plugins.shade.resource.ManifestResourceTransformer">
<mainClass>com.nk.test.Application</mainClass>
</transformer>
</transformers>
<finalName>A</finalName>
</configuration>
</execution>
</executions>
</plugin>**
</plugins>
</build>
</project>
Dependency module B
<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>com.nk.test</groupId>
<artifactId>B</artifactId>
<version>0.0.1-SNAPSHOT</version>
</project>
Dependenc Module C
<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>com.nk.test</groupId>
<artifactId>C</artifactId>
<version>0.0.1-SNAPSHOT</version>
</project>
run maven install on parent project.
This will result in Fat jar named named A.jar with B and C as dependencies inside it.
you can find example at : https://github.com/nomanbplmp/maven-multimodule-fat-jar