[JAVA] Correct generation of schema default values of type object

[DavidGrath]

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#21051
@martin-mfg , please help review

I think I've covered all the proper schema sub-types, here's what a newly generated sample looks like:

public class Test {
  public static final String SERIALIZED_NAME_TEST_EMPTY_INLINE_OBJECT = "testEmptyInlineObject";
  @SerializedName(SERIALIZED_NAME_TEST_EMPTY_INLINE_OBJECT)
  @javax.annotation.Nullable
  private Object testEmptyInlineObject = new Object();

  public static final String SERIALIZED_NAME_TEST_COMPLEX_INLINE_OBJECT = "testComplexInlineObject";
  @SerializedName(SERIALIZED_NAME_TEST_COMPLEX_INLINE_OBJECT)
  @javax.annotation.Nullable
  private TestTestComplexInlineObject testComplexInlineObject = new TestTestComplexInlineObject().foo("bar").fooInt(28).fooLong(5000000000l).fooBool(true).fooFloat(32.5f).fooDouble(3332.555d).fooNumber(new java.math.BigDecimal("120.6")).fooDateTime(java.time.OffsetDateTime.parse("2000-01-01T20:20:20+00:00", java.time.format.DateTimeFormatter.ISO_ZONED_DATE_TIME.withZone(java.time.ZoneId.systemDefault()))).fooUUID(java.util.UUID.fromString("a0ed70ec-5fe5-415a-be97-a7bf13db9fb6"))._void("empty");

  public static final String SERIALIZED_NAME_TEST_NULLABLE_EMPTY_INLINE_OBJECT = "testNullableEmptyInlineObject";
  @SerializedName(SERIALIZED_NAME_TEST_NULLABLE_EMPTY_INLINE_OBJECT)
  @javax.annotation.Nullable
  private Object testNullableEmptyInlineObject = new Object();

  public static final String SERIALIZED_NAME_TEST_NULLABLE_COMPLEX_INLINE_OBJECT = "testNullableComplexInlineObject";
  @SerializedName(SERIALIZED_NAME_TEST_NULLABLE_COMPLEX_INLINE_OBJECT)
  @javax.annotation.Nullable
  private TestTestNullableComplexInlineObject testNullableComplexInlineObject = new TestTestNullableComplexInlineObject().foo("bar");

  public static final String SERIALIZED_NAME_TEST_EMPTY_REFERENCE = "testEmptyReference";
  @SerializedName(SERIALIZED_NAME_TEST_EMPTY_REFERENCE)
  @javax.annotation.Nullable
  private Object testEmptyReference = new Object();

  public static final String SERIALIZED_NAME_TEST_COMPLEX_REFERENCE = "testComplexReference";
  @SerializedName(SERIALIZED_NAME_TEST_COMPLEX_REFERENCE)
  @javax.annotation.Nullable
  private ComplexReferenceObject testComplexReference = new ComplexReferenceObject().foo("bar");

  public static final String SERIALIZED_NAME_TEST_NULLABLE_EMPTY_REFERENCE = "testNullableEmptyReference";
  @SerializedName(SERIALIZED_NAME_TEST_NULLABLE_EMPTY_REFERENCE)
  @javax.annotation.Nullable
  private Object testNullableEmptyReference = new Object();

  public static final String SERIALIZED_NAME_TEST_NULLABLE_COMPLEX_REFERENCE = "testNullableComplexReference";
  @SerializedName(SERIALIZED_NAME_TEST_NULLABLE_COMPLEX_REFERENCE)
  @javax.annotation.Nullable
  private NullableComplexReferenceObject testNullableComplexReference = new NullableComplexReferenceObject().foo("bar");
...
}

This is probably a non-issue, but testComplexInlineObject has a very long line, do you have any ideas on how I can break it apart neatly, or should I leave it as-is?

[DavidGrath]

Oh, yeah, I suspected and confirmed that the same thing happens in Kotlin, should I modify AbstractKotlinCodegen in a similar way and make a separate PR for that?

[DavidGrath]

My bad. Forgot to update the test case, too