Production-oriented JSON-RPC 2.0 server library for Java, with optional Spring WebMVC and Spring Boot integration.

• JSON-RPC 2.0 compliant core request/response/error handling
• Pure Java support (jsonrpc-core) for custom transports
• Spring WebMVC transport adapter and Spring Boot auto-configuration
• Multiple registration styles (annotation/manual/typed)
• Explicit extension points (parser/validator/invoker/exception mapping/interceptors/metrics)
• Focused dependency surface (no direct Guava, Commons Lang3, or Jakarta Validation dependency)

• JSON-RPC 2.0: https://www.jsonrpc.org/specification
• RFC 8259 (JSON): https://www.rfc-editor.org/rfc/rfc8259

• Java: 17+
• Spring Boot baseline: 4.0.2
• Jackson baseline: 3.0.x
• Build: Gradle with Version Catalog
• CI matrix: Java 17, 21, 25

Maven:

<dependency>
  <groupId>io.github.limehee</groupId>
  <artifactId>jsonrpc-spring-boot-starter</artifactId>
  <version>0.1.0</version>
</dependency>

Gradle (Kotlin DSL):

implementation("io.github.limehee:jsonrpc-spring-boot-starter:0.1.0")

Gradle (Groovy DSL):

implementation 'io.github.limehee:jsonrpc-spring-boot-starter:0.1.0'

Maven:

<dependency>
  <groupId>io.github.limehee</groupId>
  <artifactId>jsonrpc-core</artifactId>
  <version>0.1.0</version>
</dependency>

Gradle (Kotlin DSL):

implementation("io.github.limehee:jsonrpc-core:0.1.0")

Gradle (Groovy DSL):

implementation 'io.github.limehee:jsonrpc-core:0.1.0'

import com.limehee.jsonrpc.core.JsonRpcMethod;
import com.limehee.jsonrpc.core.JsonRpcParam;
import org.springframework.stereotype.Service;

@Service
class GreetingRpcService {

    @JsonRpcMethod("greet")
    public String greet(@JsonRpcParam("name") String name) {
        return "hello " + name;
    }
}

Default endpoint: POST /jsonrpc

Request:

{"jsonrpc":"2.0","method":"greet","params":{"name":"developer"},"id":1}

Response:

{"jsonrpc":"2.0","id":1,"result":"hello developer"}

import tools.jackson.databind.JsonNode;
import tools.jackson.databind.ObjectMapper;
import tools.jackson.databind.json.JsonMapper;
import tools.jackson.databind.node.StringNode;
import com.limehee.jsonrpc.core.JsonRpcDispatchResult;
import com.limehee.jsonrpc.core.JsonRpcDispatcher;

ObjectMapper mapper = JsonMapper.builder().build();
JsonRpcDispatcher dispatcher = new JsonRpcDispatcher();

dispatcher.register("ping", params -> StringNode.valueOf("pong"));

JsonNode payload = mapper.readTree("""
{"jsonrpc":"2.0","method":"ping","id":1}
""");

JsonRpcDispatchResult result = dispatcher.dispatch(payload);
System.out.println(mapper.writeValueAsString(result.singleResponse().orElseThrow()));

Supported styles:

1. @JsonRpcMethod on Spring beans
2. JsonRpcMethodRegistration beans (manual)
3. JsonRpcTypedMethodHandlerFactory (typed adapter used by manual or custom registration)

Registration order in Spring Boot runtime:

1. JsonRpcMethodRegistration beans are registered first (orderedStream(); @Order applies).
2. @JsonRpcMethod scanning runs after singleton initialization and registers annotated methods.

Conflict behavior for duplicate method names is controlled by jsonrpc.method-registration-conflict-policy:

• REJECT (default): throws and fails startup/runtime registration.
• REPLACE: later registration replaces earlier one.

Practical implication with REPLACE: annotated methods can override manual registrations for the same name because annotation scanning executes later.

• @JsonRpcMethod("name"): explicit JSON-RPC name.
• @JsonRpcMethod without value: Java method name is used.
• Multi-parameter binding mode:
  • params object -> named binding (@JsonRpcParam first, then Java parameter names with -parameters)
  • params array -> positional binding (exact argument count required)
• Single parameter -> entire params node mapped to declared type.
• Return values are serialized via Jackson (ObjectMapper.valueToTree by default).

./gradlew check
./gradlew apiCompat -PapiBaselineVersion=<released-version>
./gradlew :jsonrpc-core:jmh
./gradlew :jsonrpc-core:jmhQuick
./scripts/verify-consumer-smoke.sh

Detailed docs are under docs/:

• docs/index.md
• docs/getting-started.md
• docs/spring-boot-guide.md
• docs/pure-java-guide.md
• docs/registration-and-binding.md
• docs/configuration-reference.md
• docs/extension-points.md
• docs/protocol-and-compliance.md
• docs/testing-and-quality.md
• docs/performance.md
• docs/troubleshooting.md

• Spring Boot sample app: samples/spring-boot-demo

Run:

./gradlew -p samples/spring-boot-demo bootRun

• Contributing: CONTRIBUTING.md
• Security: SECURITY.md
• Release checklist: docs/release-checklist.md
• Releases: https://github.com/limehee/jsonrpc-spring-boot-starter/releases