How to use

setField

method

in

com.google.protobuf.Message$Builder

/**
 * {@inheritDoc}
 */
@Override
public void setPropertyValue(Object bean, Object value, FieldMap fieldMap) {
  if (!(bean instanceof ProtoBeanBuilder)) {
    throw new MappingException("Expected a ProtoBeanBuilder instance, but got "
                  + bean.getClass().getCanonicalName());
  }
  ProtoBeanBuilder builder = (ProtoBeanBuilder)bean;
  value = ProtoUtils.wrapEnums(value);
  if (value != null) {
    if (getFieldDescriptor().isMapField()) {
      // Capitalize the first letter of the string;
      String propertyName = Character.toUpperCase(fieldName.charAt(0)) + fieldName.substring(1);
      String methodName = String.format("putAll%s", propertyName);
      try {
        Method mapSetterMethod = builder.internalProtoBuilder().getClass().getMethod(methodName, Map.class);
        mapSetterMethod.invoke(builder.internalProtoBuilder(), value);
      } catch (NoSuchMethodException | IllegalAccessException | InvocationTargetException ex) {
        throw new MappingException("Could not call map setter method " + methodName, ex);
      }
    } else {
      builder.internalProtoBuilder().setField(getFieldDescriptor(), value);
    }
  } else {
    builder.internalProtoBuilder().clearField(getFieldDescriptor());
  }
}

private static void eagerlyMergeMessageSetExtension(
  CodedInputStream input,
  ExtensionRegistry.ExtensionInfo extension,
  ExtensionRegistryLite extensionRegistry,
  Message.Builder builder,
  FieldSet<FieldDescriptor> extensions) throws IOException {
 FieldDescriptor field = extension.descriptor;
 Message value = null;
 if (hasOriginalMessage(builder, extensions, field)) {
  Message originalMessage =
    getOriginalMessage(builder, extensions, field);
  Message.Builder subBuilder = originalMessage.toBuilder();
  input.readMessage(subBuilder, extensionRegistry);
  value = subBuilder.buildPartial();
 } else {
  value = input.readMessage(extension.defaultInstance.getParserForType(),
   extensionRegistry);
 }
 if (builder != null) {
  builder.setField(field, value);
 } else {
  extensions.setField(field, value);
 }
}

 builder.addRepeatedField(field, value);
} else {
 builder.setField(field, value);

/** helper method to handle {@code builder} and {@code extensions}. */
private static void setField(
  Message.Builder builder,
  FieldSet<FieldDescriptor> extensions,
  FieldDescriptor field,
  Object value) {
 if (builder != null) {
  builder.setField(field, value);
 } else {
  extensions.setField(field, value);
 }
}

private static void handleValue(Tokenizer tokenizer,
    ExtensionRegistry extensionRegistry,
    Message.Builder builder,
    FieldDescriptor field,
    ExtensionRegistry.ExtensionInfo extension,
    boolean unknown) throws ParseException {
  Object value = null;
  if (field.getJavaType() == FieldDescriptor.JavaType.MESSAGE) {
    value = handleObject(tokenizer, extensionRegistry, builder, field, extension, unknown);
  } else {
    value = handlePrimitive(tokenizer, field);
  }
  if (value != null) {
    if (field.isRepeated()) {
      builder.addRepeatedField(field, value);
    } else {
      builder.setField(field, value);
    }
  }
}

builder.setField(messageDescriptor.getField("__actual_type"), sClass.getSimpleName());
builder.setField(messageDescriptor.getField("__" + sClass.getSimpleName()), convertSObjectToProtocolBuffersObject(object, sClass));
    if (value.getClass().isPrimitive() || value.getClass() == String.class || value.getClass() == Long.class || value.getClass() == Double.class
        || value.getClass() == Integer.class || value.getClass() == Boolean.class) {
      builder.setField(fieldDescriptor, value);
    } else if (value.getClass().isEnum()) {
      Enum eNum = (Enum) value;
      int ordinal = eNum.ordinal();
      EnumValueDescriptor findValueByNumber = fieldDescriptor.getEnumType().findValueByNumber(ordinal);
      builder.setField(fieldDescriptor, findValueByNumber);
    } else if (value.getClass() == Date.class) {
      builder.setField(fieldDescriptor, ((Date) value).getTime());
    } else if (value.getClass() == DataHandler.class) {
      DataHandler dataHandler = (DataHandler) value;
      IOUtils.copy(inputStream, byteArrayOutputStream);
      ByteString byteString = ByteString.copyFrom(byteArrayOutputStream.toByteArray());
      builder.setField(fieldDescriptor, byteString);
    } else if (List.class.isAssignableFrom(value.getClass())) {
      List list = (List) value;
      builder.setField(fieldDescriptor, newList);
    } else {
      LOGGER.error("Unimplemented: " + fieldDescriptor.getName() + ": " + value);

Builder builder = response.newBuilderForType();
if (methodDescriptor.getOutputDescriptor().getName().equals("VoidResponse")) {
  builder.setField(errorMessageField, "OKE");
} else {
  FieldDescriptor valueField = protocolBuffersMetaData.getMessageDescriptor(response.getDescriptorForType().getName()).getField("value");
  if (result != null) {
    if (valueField.getType().getJavaType() == JavaType.ENUM) {
      builder.setField(valueField, valueField.getEnumType().findValueByName(result.toString()));
    } else if (valueField.getType().getJavaType() != JavaType.MESSAGE) {
      if (result instanceof Date) {
        builder.setField(valueField, ((Date)result).getTime());
      } else {
        if (valueField.isRepeated()) {
          builder.setField(valueField, new ArrayList());
        } else {
          builder.setField(valueField, result);
      builder.setField(valueField, list);
    } else if (result instanceof Set) {
      List list = new ArrayList();
      builder.setField(valueField, list);
    } else {
      builder.setField(valueField, convertSObjectToProtocolBuffersObject((SBase) result, sMethod.getBestReturnType()));
  builder.setField(errorMessageField, "OKE");
  errorMessage.setField(errorMessageField, e.getMessage());
} else {

 builder.setField(field, lazyField);
} else {
 builder.setField(field, lazyField.getValue());

@Override
public void copy(@Nonnull Descriptors.Descriptor recordDescriptor, @Nonnull Message.Builder recordBuilder,
         @Nonnull IndexEntry kv) {
  final Descriptors.FieldDescriptor fieldDescriptor = recordDescriptor.findFieldByName(field);
  switch (fieldDescriptor.getType()) {
    case MESSAGE:
      break;
    default:
      throw new RecordCoreException("only nested message should be handled by MessageCopier");
  }
  recordBuilder.setField(fieldDescriptor, nested.toRecord(fieldDescriptor.getMessageType(), kv));
}

 @Override
 public void add(Object value) {
  parentBuilder.setField(fieldDescriptor, value);
 }
};

@Override
public Object setStructFieldData(Object data, StructField field, Object fieldValue) {
 return ((Message) data)
   .toBuilder()
   .setField(descriptor.findFieldByName(field.getFieldName()), fieldValue)
   .build();
}

 @Override
 protected void populate(V builder, JsonParser parser, DeserializationContext context) throws IOException {
  FieldDescriptor field = builder.getDescriptorForType().findFieldByName("value");
  Object value = readValue(builder, field, null, parser, context);
  builder.setField(field, value);
 }
}

public static void setFieldSafely(Message.Builder builder, Descriptors.FieldDescriptor fd, List<String> value)
    throws InvalidProtocolBufferException {
  Object valueToSet = getValueFor(fd, value);
  builder.setField(fd, valueToSet);
}

private void mergeWrapper(JsonElement json, Message.Builder builder)
  throws InvalidProtocolBufferException {
  Descriptor type = builder.getDescriptorForType();
  FieldDescriptor field = type.findFieldByName("value");
  if (field == null) {
    throw new InvalidProtocolBufferException("Invalid wrapper type: " + type.getFullName());
  }
  builder.setField(field, parseFieldValue(field, json, builder));
}

private void setRequestedState() throws CouldNotPerformException {
  try (ClosableDataBuilder dataBuilder = unit.getDataBuilder(this)) {
    // set the responsible action for the service attribute
    Message.Builder serviceStateBuilder = serviceAttribute.toBuilder();
    Descriptors.FieldDescriptor fieldDescriptor = ProtoBufFieldProcessor.getFieldDescriptor(serviceStateBuilder, Service.RESPONSIBLE_ACTION_FIELD_NAME);
    serviceStateBuilder.setField(fieldDescriptor, actionDescriptionBuilder.build());
    // set the updated service attribute as requested state in the unit data builder
    Services.invokeServiceMethod(serviceDescription.getType(), serviceDescription.getPattern(), ServiceTempus.REQUESTED, dataBuilder.getInternalBuilder(), serviceStateBuilder);
  }
}

@Override
protected void setField(Object r, String n, int pos, Object o, Object state) {
 Builder b = (Builder)r;
 FieldDescriptor f = ((FieldDescriptor[])state)[pos];
 switch (f.getType()) {
 case MESSAGE:
  if (o == null) {
   b.clearField(f);
   break;
  }
 default:
  b.setField(f, o);
 }
}

@Override
public MergeTarget setField(Descriptors.FieldDescriptor field, Object value) {
 builder.setField(field, value);
 return this;
}

@Override
public MergeTarget setField(Descriptors.FieldDescriptor field, Object value) {
 builder.setField(field, value);
 return this;
}

public MergeTarget setField(Descriptors.FieldDescriptor field,
  Object value) {
 builder.setField(field, value);
 return this;
}

@Override
protected void setUnionField(@Nonnull RecordMetaData metaData,
               @Nonnull RecordType recordType,
               @Nonnull Message.Builder unionBuilder,
               @Nonnull Message record) {
  Descriptors.FieldDescriptor unionField = metaData.getUnionFieldForRecordType(recordType);
  unionBuilder.setField(unionField, record);
}