title: Can't generate Birt Report, Report engine fails to initialize null emitter
body: <p><br/>
  I'm using BIRT Runtime Release Build: 4.4.1<br/>
  I'm facing EngineException when I try to generate a Birt report.<br/>
  Here is the code:</p>
  
  <pre><code>        try {
          final EngineConfig config = new EngineConfig();
          // delete the following line if using BIRT 3.7 (or later) POJO
          // runtime
          // As of 3.7.2, BIRT now provides an OSGi and a POJO Runtime.
  
          config.setEngineHome("C:/Mine/ReportEngine/lib");
          // config.setLogConfig(c:/temp, Level.FINE);
  
          Platform.startup(config);
          // If using RE API in Eclipse/RCP application this is not needed.
          IReportEngineFactory factory = (IReportEngineFactory) Platform
                  .createFactoryObject(IReportEngineFactory.EXTENSION_REPORT_ENGINE_FACTORY);
          IReportEngine engine = factory.createReportEngine(config);
          engine.changeLogLevel(Level.WARNING);
          IReportRunnable report = engine
                  .openReportDesign("C:/Mine/BirtTraining/demo/demo.rptdesign");
          IRunAndRenderTask task = null;
          task = engine.createRunAndRenderTask(report);
          HTMLRenderOption options = null;
          options = new HTMLRenderOption();
          options.setOutputFileName("C:/birt.html");
          task.setRenderOption(options);
  
          task.run();
  
           System.out.println("All went well. Closing program!");
           engine.destroy();
           System.exit(0);
      } catch (Exception ex) {
          ex.printStackTrace();
          System.err.println("An error occured while running the report!");
  
          System.exit(-1);
      }
  </code></pre>
  
  <p><br/>
  Here is the exception:<br/>
  Feb 1, 2015 6:32:13 PM org.eclipse.birt.report.engine.api.impl.EngineTask createContentEmitter<br/>
  SEVERE: Report engine can not create emitter null.
  Feb 1, 2015 6:32:13 PM org.eclipse.birt.report.engine.api.impl.EngineTask handleFatalExceptions<br/>
  SEVERE: An error happened while running the report. Cause:
  org.eclipse.birt.report.engine.api.EngineException: <b>Report engine fails to initialize null emitter, please make sure required libraries for this emitter are installed.</b>
      at org.eclipse.birt.report.engine.api.impl.EngineTask.createContentEmitter(EngineTask.java:1770)
      at org.eclipse.birt.report.engine.api.impl.RunAndRenderTask.doRun(RunAndRenderTask.java:106)
      at org.eclipse.birt.report.engine.api.impl.RunAndRenderTask.run(RunAndRenderTask.java:77)
      at testBirt.Main.main(Main.java:46)
  <br/><br/>
  How can I initialize an emitter?<br/>
  What are required libraries for the emitter?<br/>
  If there is a complete example to generate a report it will be great.
  Thanks in advance.</p>