com.google.protobuf.Descriptors.FieldDescriptor#getIndex ( )源码实例Demo

@SuppressWarnings("unchecked")
MessageWriter(Descriptor descriptor, GroupType schema) {
  List<FieldDescriptor> fields = descriptor.getFields();
  fieldWriters = (FieldWriter[]) Array.newInstance(FieldWriter.class, fields.size());

  for (FieldDescriptor fieldDescriptor: fields) {
    String name = fieldDescriptor.getName();
    Type type = schema.getType(name);
    FieldWriter writer = createWriter(fieldDescriptor, type);

    if(writeSpecsCompliant && fieldDescriptor.isRepeated() && !fieldDescriptor.isMapField()) {
      writer = new ArrayWriter(writer);
    }
    else if (!writeSpecsCompliant && fieldDescriptor.isRepeated()) {
      // the old schemas style used to write maps as repeated fields instead of wrapping them in a LIST
      writer = new RepeatedWriter(writer);
    }

    writer.setFieldName(name);
    writer.setIndex(schema.getFieldIndex(name));

    fieldWriters[fieldDescriptor.getIndex()] = writer;
  }
}
 

/** Get the FieldAccessor for a particular field. */
private FieldAccessor getField(final FieldDescriptor field) {
  if (field.getContainingType() != descriptor) {
    throw new IllegalArgumentException(
      "FieldDescriptor does not match message type.");
  } else if (field.isExtension()) {
    // If this type had extensions, it would subclass ExtendableMessage,
    // which overrides the reflection interface to handle extensions.
    throw new IllegalArgumentException(
      "This type does not have extensions.");
  }
  return fields[field.getIndex()];
}
 

/** Get the FieldAccessor for a particular field. */
private FieldAccessor getField(final FieldDescriptor field) {
  if (field.getContainingType() != descriptor) {
    throw new IllegalArgumentException(
      "FieldDescriptor does not match message type.");
  } else if (field.isExtension()) {
    // If this type had extensions, it would subclass ExtendableMessage,
    // which overrides the reflection interface to handle extensions.
    throw new IllegalArgumentException(
      "This type does not have extensions.");
  }
  return fields[field.getIndex()];
}
 

/** Get the FieldAccessor for a particular field. */
private FieldAccessor getField(final FieldDescriptor field) {
  if (field.getContainingType() != descriptor) {
    throw new IllegalArgumentException(
      "FieldDescriptor does not match message type.");
  } else if (field.isExtension()) {
    // If this type had extensions, it would subclass ExtendableMessage,
    // which overrides the reflection interface to handle extensions.
    throw new IllegalArgumentException(
      "This type does not have extensions.");
  }
  return fields[field.getIndex()];
}
 

/** validates mapping between protobuffer fields and parquet fields.*/
private void validatedMapping(Descriptor descriptor, GroupType parquetSchema) {
  List<FieldDescriptor> allFields = descriptor.getFields();

  for (FieldDescriptor fieldDescriptor: allFields) {
    String fieldName = fieldDescriptor.getName();
    int fieldIndex = fieldDescriptor.getIndex();
    int parquetIndex = parquetSchema.getFieldIndex(fieldName);
    if (fieldIndex != parquetIndex) {
      String message = "FieldIndex mismatch name=" + fieldName + ": " + fieldIndex + " != " + parquetIndex;
      throw new IncompatibleSchemaModificationException(message);
    }
  }
}
 

/** Get the FieldAccessor for a particular field. */
private FieldAccessor getField(final FieldDescriptor field) {
  if (field.getContainingType() != descriptor) {
    throw new IllegalArgumentException(
      "FieldDescriptor does not match message type.");
  } else if (field.isExtension()) {
    // If this type had extensions, it would subclass ExtendableMessage,
    // which overrides the reflection interface to handle extensions.
    throw new IllegalArgumentException(
      "This type does not have extensions.");
  }
  return fields[field.getIndex()];
}
 

/** Get the FieldAccessor for a particular field. */
private FieldAccessor getField(final FieldDescriptor field) {
  if (field.getContainingType() != descriptor) {
    throw new IllegalArgumentException(
      "FieldDescriptor does not match message type.");
  } else if (field.isExtension()) {
    // If this type had extensions, it would subclass ExtendableMessage,
    // which overrides the reflection interface to handle extensions.
    throw new IllegalArgumentException(
      "This type does not have extensions.");
  }
  return fields[field.getIndex()];
}