Package org.springframework.http.codec.protobuf

Class ProtobufEncoder

java.lang.Object
org.springframework.http.codec.protobuf.ProtobufCodecSupport
org.springframework.http.codec.protobuf.ProtobufEncoder
All Implemented Interfaces:
Encoder<com.google.protobuf.Message>, HttpMessageEncoder<com.google.protobuf.Message>
public class ProtobufEncoder extends ProtobufCodecSupport implements HttpMessageEncoder<com.google.protobuf.Message>
An Encoder that writes Messages using Google Protocol Buffers.

Flux are serialized using delimited Protobuf messages with the size of each message specified before the message itself. Single values are serialized using regular Protobuf message format (without the size prepended before the message).

To generate Message Java classes, you need to install the protoc binary.

This encoder requires Protobuf 3.29 or higher, and supports "application/x-protobuf" and "application/octet-stream" with the official "com.google.protobuf:protobuf-java" library.

Since:
5.1
Author:
Sebastien Deleuze
See Also:

  • Constructor Details

    • ProtobufEncoder

      public ProtobufEncoder()

  • Method Details

    • canEncode

      public boolean canEncode(ResolvableType elementType, @Nullable MimeType mimeType)
      Description copied from interface: Encoder
      Whether the encoder supports the given source element type and the MIME type for the output stream.
      Specified by:
      canEncode in interface Encoder<com.google.protobuf.Message>
      Parameters:
      elementType - the type of elements in the source stream
      mimeType - the MIME type for the output stream (can be null if not specified)
      Returns:
      true if supported, false otherwise

    • encode

      public reactor.core.publisher.Flux<DataBuffer> encode(Publisher<? extends com.google.protobuf.Message> inputStream, DataBufferFactory bufferFactory, ResolvableType elementType, @Nullable MimeType mimeType, @Nullable Map<String,Object> hints)
      Description copied from interface: Encoder
      Encode a stream of Objects of type T into a DataBuffer output stream.
      Specified by:
      encode in interface Encoder<com.google.protobuf.Message>
      Parameters:
      inputStream - the input stream of Objects to encode. If the input should be encoded as a single value rather than as a stream of elements, an instance of Mono should be used.
      bufferFactory - for creating output stream DataBuffer's
      elementType - the expected type of elements in the input stream; this type must have been previously passed to the Encoder.canEncode(org.springframework.core.ResolvableType, org.springframework.util.MimeType) method and it must have returned true.
      mimeType - the MIME type for the output content (optional)
      hints - additional information about how to encode
      Returns:
      the output stream

    • encodeValue

      public DataBuffer encodeValue(com.google.protobuf.Message message, DataBufferFactory bufferFactory, ResolvableType valueType, @Nullable MimeType mimeType, @Nullable Map<String,Object> hints)
      Description copied from interface: Encoder
      Encode an Object of type T to a data buffer. This is useful for scenarios, that distinct messages (or events) are encoded and handled individually, in fully aggregated form.

      By default this method raises UnsupportedOperationException and it is expected that some encoders cannot produce a single buffer or cannot do so synchronously (e.g. encoding a Resource).

      Specified by:
      encodeValue in interface Encoder<com.google.protobuf.Message>
      Parameters:
      message - the value to be encoded
      bufferFactory - for creating the output DataBuffer
      valueType - the type for the value being encoded
      mimeType - the MIME type for the output content (optional)
      hints - additional information about how to encode
      Returns:
      the encoded content

    • getStreamingMediaTypes

      public List<MediaType> getStreamingMediaTypes()
      Description copied from interface: HttpMessageEncoder
      Return "streaming" media types for which flushing should be performed automatically vs at the end of the input stream.
      Specified by:
      getStreamingMediaTypes in interface HttpMessageEncoder<com.google.protobuf.Message>

    • getEncodableMimeTypes

      public List<MimeType> getEncodableMimeTypes()
      Description copied from interface: Encoder
      Return the list of MIME types supported by this Encoder. The list may not apply to every possible target element type and calls to this method should typically be guarded via canEncode(elementType, null). The list may also exclude MIME types supported only for a specific element type. Alternatively, use Encoder.getEncodableMimeTypes(ResolvableType) for a more precise list.
      Specified by:
      getEncodableMimeTypes in interface Encoder<com.google.protobuf.Message>
      Returns:
      the list of supported MIME types