@Test
  public void equalsUsingPk() {
    Document model1 = new Document();
    Document model2 = new Document();

    String id = ValueGenerator.getUniqueString(32);
    model1.setId(id);
    model2.setId(id);

    model1.setDocumentContentType("a");
    model2.setDocumentContentType("a");

    model1.setDocumentSize(1);
    model2.setDocumentSize(1);

    model1.setDocumentFileName("a");
    model2.setDocumentFileName("a");

    model1.setDocumentBinary("d".getBytes());
    model2.setDocumentBinary("d".getBytes());

    model1.setVersion(1);
    model2.setVersion(1);
    assertTrue(model1.isIdSet());
    assertTrue(model2.isIdSet());
    assertTrue(model1.hashCode() == model2.hashCode());
    assertTrue(model1.equals(model2));
    assertTrue(model2.equals(model1));
  }
 @Test
 public void isIdSetReturnsTrue() {
   Document model = new Document();
   model.setId(ValueGenerator.getUniqueString(32));
   assertNotNull(model.getId());
   assertTrue(model.isIdSet());
 }
 // test unique primary key
 @Test
 public void newInstanceHasNoPrimaryKey() {
   Document model = new Document();
   assertFalse(model.isIdSet());
 }