@Test
  public void updatePlatformEntity() throws Exception {
    long existingPlatformId = 22L;
    String updatedPlatformName = "I've updated the name";

    PlatformEntity updatedPlatformEntity = new PlatformEntity();
    updatedPlatformEntity.setPlatformId(existingPlatformId);
    updatedPlatformEntity.setPlatformName(updatedPlatformName);

    PlatformEntity retrievedPlatformEntity = platformService.update(updatedPlatformEntity);

    assertThat(retrievedPlatformEntity.getPlatformId(), is(existingPlatformId));
    assertThat(retrievedPlatformEntity.getPlatformName(), is(updatedPlatformName));
    assertThat(retrievedPlatformEntity.getVideoGameEntities().isEmpty(), is(true));
  }
 private void assertionsForPlatformEntityAndChildVideoGameEntity(
     String expectedPlatformName,
     String expectedVideoGameName1,
     String expectedVideoGameName2,
     Date expectedDateReleased,
     PlatformEntity savedPlatformEntity) {
   assertThat(savedPlatformEntity.getPlatformName(), is(expectedPlatformName));
   assertThat(
       savedPlatformEntity.getVideoGameEntities(),
       IsIterableContainingInAnyOrder.<VideoGameEntity>containsInAnyOrder(
           hasProperty("videoGameName", is(expectedVideoGameName1)),
           hasProperty("dateReleased", is(expectedDateReleased))));
   assertThat(
       savedPlatformEntity.getVideoGameEntities(),
       IsIterableContainingInAnyOrder.<VideoGameEntity>containsInAnyOrder(
           hasProperty("videoGameName", is(expectedVideoGameName2)),
           hasProperty("dateReleased", is(expectedDateReleased))));
 }