public static ParameterizedType collectionOf(Type elementType) {
    return parameterizedType(Collection.class, elementType);
  }
@Test
  public void createCollectionType() {
    ParameterizedType type = Types.collectionOf(Person.class);
    assertThat(type.getRawType()).isEqualTo(Collection.class);
    assertThat(type.getActualTypeArguments()).isEqualTo(new Type[] {Person.class});
  }