Why does mirah generate a main method in this case

mirah main method

mirah code
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package org.eclipse.ecf.examples.sharedobject.server

import org.eclipse.ecf.core.ContainerFactory
import org.eclipse.ecf.core.IContainer
import org.eclipse.ecf.core.identity.ID
import org.eclipse.ecf.core.identity.IDFactory
import org.osgi.framework.BundleActivator
import org.osgi.framework.BundleContext

class Activator 
implements BundleActivator
   
  def start(context:BundleContext) throws Exception
    @myserver = createServer("ecf.generic.server",  "ecftcp://localhost:4280/mygroup")
    puts "Server has been created on #{"ecftcp://localhost:4280/mygroup"}"
  end
 
  def stop(context:BundleContext) throws Exception
    @myserver.dispose if @myserver
  end

  def createServer(container_str:String, connection_id_str:String)
    idFactory = IDFactory.getDefault
    connection_id = idFactory.createStringID(connection_id_str)
    containerFactory = ContainerFactory.getDefault
    return containerFactory.createContainer(container_str, connection_id)
  end
  
end
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generated code
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// Generated from Activator.mirah
package org.eclipse.ecf.examples.sharedobject.server;
public class Activator extends java.lang.Object implements org.osgi.framework.BundleActivator {
  private org.eclipse.ecf.core.IContainer myserver;
  public static void main(java.lang.String[] argv) {
  public void start(org.osgi.framework.BundleContext context) throws java.lang.Exception {
    this.myserver = this.createServer("ecf.generic.server", "ecftcp://localhost:4280/mygroup");
    java.io.PrintStream temp$1 = java.lang.System.out;
    temp$1.println("Server has been created on " + "ecftcp://localhost:4280/mygroup");
  }
  public void stop(org.osgi.framework.BundleContext context) throws java.lang.Exception {
    if ((this.myserver != null)) {
      org.eclipse.ecf.core.IContainer temp$1 = this.myserver;
      temp$1.dispose();
    }
  }
  public org.eclipse.ecf.core.IContainer createServer(java.lang.String container_str, java.lang.String connection_id_str) {
    org.eclipse.ecf.core.identity.IIDFactory idFactory = null;
    org.eclipse.ecf.core.identity.ID connection_id = null;
    org.eclipse.ecf.core.IContainerFactory containerFactory = null;
    idFactory = org.eclipse.ecf.core.identity.IDFactory.getDefault();
    connection_id = idFactory.createStringID(connection_id_str);
    containerFactory = org.eclipse.ecf.core.ContainerFactory.getDefault();
    return containerFactory.createContainer(container_str, connection_id);
  }
}