code: public void testUpdateModelPersistence() throws Exception {
    Model model=repositoryService.newModel();
    assertNotNull(model);
    model.setName("Test model");
    model.setCategory("test");
    model.setMetaInfo("meta");
    repositoryService.saveModel(model);
    assertNotNull(model.getId());
    model=repositoryService.getModel(model.getId());
    assertNotNull(model);
    model.setName("New name");
    model.setCategory("New category");
    model.setMetaInfo("test");
    model.setVersion(2);
    repositoryService.saveModel(model);
    assertNotNull(model.getId());
    repositoryService.addModelEditorSource(model.getId(),"new".getBytes("utf-8"));
    repositoryService.addModelEditorSourceExtra(model.getId(),"new".getBytes("utf-8"));
    model=repositoryService.getModel(model.getId());
    assertEquals("New name",model.getName());
    assertEquals("New category",model.getCategory());
    assertEquals("test",model.getMetaInfo());
    assertNotNull(model.getCreateTime());
    assertEquals(Integer.valueOf(2),model.getVersion());
    assertEquals("new",new String(repositoryService.getModelEditorSource(model.getId()),"utf-8"));
    assertEquals("new",new String(repositoryService.getModelEditorSourceExtra(model.getId()),"utf-8"));
    repositoryService.deleteModel(model.getId());
  }
  