<?xml version="1.0" encoding="UTF-8"?>
<definition>
     <import>
          <package>de.lmu.ifi.dbs.knowing.core.model</package>
          <package>de.lmu.ifi.dbs.knowing.debug.ui.handler</package>
          <package>de.lmu.ifi.dbs.knowing.debug.ui.editor</package>
     </import>
....

     <action>
          <id>knowing.dpu.run</id>
          <label>Run</label>
     </action>
     <action-handler>
          <action>knowing.dpu.run</action>
          <id>knowing.dpu.run.handler.default</id>
          <impl>de.lmu.ifi.dbs.knowing.debug.ui.handler.SapphireRunHandler</impl>
     </action-handler>
....

package de.lmu.ifi.dbs.knowing.debug.ui.handler;

import org.eclipse.sapphire.ui.SapphireActionHandler;
import org.eclipse.sapphire.ui.SapphireRenderingContext;

public class SapphireRunHandler extends SapphireActionHandler {

	@Override
	protected Object run(SapphireRenderingContext context) {
		System.out.println("RUN!");
		return null;
	}

}