Programmatic ProtoStream Marshalling

What You Will Learn

How to define a Protobuf schema in Java code using the Schema.Builder API, implement a custom MessageMarshaller, and register both with the Hot Rod client — all without using @Proto annotations.

Prerequisites

Java 17+
An Infinispan Server running on localhost:11222 (or Docker/Podman available for Testcontainers)

Step 1: Define the Data Model and Schema

Create a simple Java record for the entity:

public record Magazine(String name, YearMonth publicationDate, List<String> stories) {
}

Use the Schema.Builder API to define the schema in code:

    static public Schema magazineSchema() {
        return new Schema.Builder("magazine.proto")
                .packageName("magazine_sample")
                .addMessage("Magazine")
                .addField(Type.Scalar.STRING, "name", 1)
                .addField(Type.Scalar.INT32, "publicationYear", 2)
                .addField(Type.Scalar.INT32, "publicationMonth", 3)
                .addRepeatedField(Type.Scalar.STRING, "stories", 4)
                .build();
    }

Step 2: Implement and Register the Marshaller

Create a MessageMarshaller to convert between your Java type and Protobuf, then register the schema and marshaller with the ProtoStreamMarshaller and upload the schema to the server:

      ProtoStreamMarshaller marshaller = new ProtoStreamMarshaller();
      SerializationContext serializationContext = marshaller.getSerializationContext();
      FileDescriptorSource fds = FileDescriptorSource.fromString(schema.getName(), schema.toString());
      serializationContext.registerProtoFiles(fds);
      serializationContext.registerMarshaller(new MagazineMarshaller());
      builder.marshaller(marshaller);
      builder.remoteCache(TUTORIAL_CACHE_NAME);

      // Connect to the server
      client = TutorialsConnectorHelper.connect(builder);

      // Create and add the Protobuf schema in the server
      client.administration().schemas().createOrUpdate(schema);

The MagazineMarshaller implements MessageMarshaller<Magazine> with readFrom and writeTo methods that map record fields to Protobuf fields.

Step 3: Run the Tutorial

mvn package exec:java

You should see a magazine entry printed from the cache, confirming the programmatic schema and marshaller work correctly.

What’s Next

Query your data with Ickle queries and annotation-based schemas
Getting started with basic cache operations