Multiple commands with Maven Exec plugin - maven

Question

I am struggeling a bit with the Maven Exec plugin. I want to execute two seperate mvn commands using the plugin so I only need to execute mvn exec:exec in order to execute all commands.
The following two commands work well seperately:
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.6.0</version>
<configuration>
<executable>mvn</executable>
<arguments>
<argument>clean</argument>
</arguments>
</configuration>
</plugin>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.6.0</version>
<configuration>
<executable>mvn</executable>
<arguments>
<argument>package</argument>
</arguments>
</configuration>
</plugin>
And this is my attempt to combine both in order to execute them with one command:
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.6.0</version>
<executions>
<execution>
<id>id1</id>
<phase>package</phase>
<goals>
<goal>exec</goal>
</goals>
<configuration>
<executable>mvn</executable>
<arguments>
<argument>clean</argument>
</arguments>
</configuration>
</execution>
<execution>
<id>id2</id>
<phase>package</phase>
<goals>
<goal>exec</goal>
</goals>
<configuration>
<executable>mvn</executable>
<arguments>
<argument>package</argument>
</arguments>
</configuration>
</execution>
</executions>
</plugin>
Unfortunately, when I now execute mvn exec:exec I receive the following error message:
[INFO] Scanning for projects...
[INFO]
[INFO] Using the builder org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder with a thread count of 1
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building MyProjet 0.0.1-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- exec-maven-plugin:1.6.0:exec (default-cli) # MyProject ---
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 0.787 s
[INFO] Finished at: 2017-09-26T09:56:57+01:00
[INFO] Final Memory: 6M/15M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.codehaus.mojo:exec-maven-plugin:1.6.0:exec (default-cli) on project MyProject: The parameter 'executable' is missing or invalid -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoExecutionException

Answer 1

When you run mvn exec:exec on the command-line, it runs an <execution> with an <id> of default-cli. This explains the error message, as there is no execution with <id>default-cli</id> that has an <executable> configured in your POM.
To solve your problem, have a look at the Guide to Configuring Plug-ins. It explains how to execute a goal from the command-line with an <id> other than default-cli:
mvn exec:exec#id1 exec:exec#id2