public static AvroGenericCoder of(Schema schema) {
    return AvroGenericCoder.of(schema);
  }
@Test
  public void testDeterminismUnion() {
    assertDeterministic(AvroCoder.of(DeterministicUnionBase.class));
    assertNonDeterministic(
        AvroCoder.of(NonDeterministicUnionBase.class),
        reasonField(UnionCase3.class, "mapField", "may not be deterministically ordered"));
  }