Optional jar inclusion in fat jar in maven plugin

Question

How to create a fat jar with specific dependencies. I have spark project which need 2 external jar which I wanted to add in application jar. when I am creating executable jar then no dependency is included in jar and when I create fat jar all the dependencies are getting added including spark etc.. I wanted to add only those 2 jars in my jar. below is the pom file I created using maven assembly plugin.

<dependencies>

    <dependency>
        <groupId>org.apache.spark</groupId>
        <artifactId>spark-core_2.11</artifactId>
        <version>2.2.0</version>
    </dependency>
    <dependency>
        <groupId>org.apache.spark</groupId>
        <artifactId>spark-sql_2.11</artifactId>
        <version>2.2.0</version>
    </dependency>

    <!-- Below dependencies need to be added in Application jar -->

    <dependency>
        <groupId>netacuity</groupId>
        <artifactId>common-netacuity-db</artifactId>
        <version>3.1.2</version>
    </dependency>
    <dependency>
        <groupId>netacuity</groupId>
        <artifactId>common</artifactId>
        <version>2.1.1</version>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-assembly-plugin</artifactId>
            <version>2.4.1</version>
            <configuration>
                <!-- get all project dependencies -->
                <descriptorRefs>
                    <descriptorRef>jar-with-dependencies</descriptorRef>
                </descriptorRefs>
                <!-- MainClass in mainfest make a executable jar -->
                <archive>
                    <manifest>
                        <mainClass>com....App</mainClass>
                    </manifest>
                </archive>

            </configuration>
            <executions>
                <execution>
                    <id>make-assembly</id>
                    <!-- bind to the packaging phase -->
                    <phase>package</phase>
                    <goals>
                        <goal>single</goal>
                    </goals>
                </execution>
            </executions>
        </plugin>

Answer 1

You can use the scope for this. By default scope is compile and so all the jars will be included when you package it.

To include a jar you can either provide scope as compile and keep the default

    <dependency>
        <groupId>netacuity</groupId>
        <artifactId>common-netacuity-db</artifactId>
        <version>3.1.2</version>
        <scope>compile</scope>
    </dependency>

To exclude the jar, you can change the scope to provided. These jars should be available during runtime.

    <dependency>
        <groupId>org.apache.spark</groupId>
        <artifactId>spark-sql_2.11</artifactId>
        <version>2.2.0</version>
        <scope>provided</scope>
    </dependency>