How to use

isReadOnly

method

in

com.facebook.swift.codec.metadata.ThriftFieldMetadata

@Override
public void write(T instance, TProtocol protocol)
    throws Exception
{
  TProtocolWriter writer = new TProtocolWriter(protocol);
  Short idValue = (Short) getFieldValue(instance, idField.getKey());
  writer.writeStructBegin(metadata.getStructName());
  if (metadataMap.containsKey(idValue)) {
    ThriftFieldMetadata fieldMetadata = metadataMap.get(idValue);
    if (fieldMetadata.isReadOnly() || fieldMetadata.getType() != THRIFT_FIELD) {
      throw new IllegalStateException(format("Field %s is not readable", fieldMetadata.getName()));
    }
    Object fieldValue = getFieldValue(instance, fieldMetadata);
    // write the field
    if (fieldValue != null) {
      @SuppressWarnings("unchecked")
      ThriftCodec<Object> codec = (ThriftCodec<Object>) fields.get(fieldMetadata.getId());
      writer.writeField(fieldMetadata.getName(), fieldMetadata.getId(), codec, fieldValue);
    }
  }
  writer.writeStructEnd();
}

  private <T> void verifyField(ThriftStructMetadata metadata, int id, String name)
  {
    ThriftFieldMetadata messageField = metadata.getField(id);
    assertNotNull(messageField, "field '" + name + "' is null");
    assertEquals(messageField.getId(), id);
    assertEquals(messageField.getName(), name);
    assertFalse(messageField.isReadOnly());
    assertFalse(messageField.isWriteOnly());

    assertTrue(messageField.getExtraction().isPresent());
    ThriftExtraction extraction = messageField.getExtraction().get();
    assertEquals(extraction.getId(), id);
    assertEquals(extraction.getName(), name);

    assertNotNull(messageField.getInjections());
    assertEquals(messageField.getInjections().size(), 1);
    ThriftInjection injection = messageField.getInjections().get(0);
    assertEquals(injection.getId(), id);
    assertEquals(injection.getName(), name);
  }
}

  private <T> void verifyField(ThriftStructMetadata metadata, int id, String name)
  {
    ThriftFieldMetadata metadataField = metadata.getField(id);
    assertNotNull(metadataField, "metadataField is null");
    assertEquals(metadataField.getId(), id);
    assertEquals(metadataField.getName(), name);
    assertFalse(metadataField.isReadOnly());
    assertFalse(metadataField.isWriteOnly());

    assertTrue(metadataField.getExtraction().isPresent());
    ThriftExtraction extraction = metadataField.getExtraction().get();
    assertEquals(extraction.getId(), id);
    assertEquals(extraction.getName(), name);

    assertNotNull(metadataField.getInjections());
    assertEquals(metadataField.getInjections().size(), 1);
    ThriftInjection injection = metadataField.getInjections().get(0);
    assertEquals(injection.getId(), id);
    assertEquals(injection.getName(), name);
  }
}

if (field.isReadOnly() || field.getType() != THRIFT_FIELD) {
  reader.skipFieldData();
  continue;