title: Using spring-boot-maven-plugin to generate multiple runnable JAR
body: <p>I have 2 classes with main method in my project.
  When I use spring-boot-starter-parent 2.0.0, I can generate 2 runnable JARs by configuration:</p>
  
  <pre><code>&lt;groupId&gt;org.springframework.boot&lt;/groupId&gt;
  &lt;artifactId&gt;spring-boot-maven-plugin&lt;/artifactId&gt;
  &lt;executions&gt;
      &lt;execution&gt;
          &lt;id&gt;default&lt;/id&gt;
          &lt;goals&gt;
              &lt;goal&gt;repackage&lt;/goal&gt;
          &lt;/goals&gt;
          &lt;configuration&gt;
              &lt;mainClass&gt;com.myproj.Importer&lt;/mainClass&gt;
              &lt;classifier&gt;importer&lt;/classifier&gt;
          &lt;/configuration&gt;
      &lt;/execution&gt;
      &lt;execution&gt;
          &lt;id&gt;exe2&lt;/id&gt;
          &lt;goals&gt;
              &lt;goal&gt;repackage&lt;/goal&gt;
          &lt;/goals&gt;
          &lt;configuration&gt;
              &lt;mainClass&gt;com.myproj.Reporter&lt;/mainClass&gt;
              &lt;classifier&gt;reporter&lt;/classifier&gt;
          &lt;/configuration&gt;
      &lt;/execution&gt;
  
  </code></pre>
  
  <p>maven package log is</p>
  
  <pre><code>[INFO] --- maven-jar-plugin:3.1.1:jar (default-jar) @ utility ---
  [INFO] Building jar: D:\Workspaces\utility\target\utility-1.0.jar
  [INFO] 
  [INFO] --- spring-boot-maven-plugin:2.0.0.RELEASE:repackage (default) @ utility ---
  [INFO] Attaching archive: D:\Workspaces\utility\target\utility-1.0-importer.jar, with classifier: importer
  [INFO] 
  [INFO] --- spring-boot-maven-plugin:2.0.0.RELEASE:repackage (exe2) @ utility ---
  [INFO] Attaching archive: D:\Workspaces\utility\target\utility-1.0-reporter.jar, with classifier: reporter
  </code></pre>
  
  <p>the JAR can be run like: <code>java -jar utility-1.0-importer.jar</code> &amp; <code>java -jar utility-1.0-reporter.jar</code></p>
  
  <p>But when I use newest spring-boot-starter-parent 2.2.1.RELEASE, same configuration produce 
  <code>Unable to find a single main class</code> problem and I can't find alternative way to do the same thing.</p>
  
  <p>Any help is appreciated!</p>