MeshJob: Java SDK parity for event injection (recvEvent/sendEvent/postEvent)

[dhyansraj]

Summary

Extend the Java SDK with MeshJob event-injection parity following the Python (#1041) and TypeScript (#1043) verticals already shipped for issue #1032.

Completes the original MeshJob cross-runtime shipping pattern: Python (#861/#878) → TypeScript (#885) → Java (#891). This is the Java step for the new event-injection primitive.

Scope

FFI bindings (src/runtime/core/src/jobs_ffi.rs)

• mesh_job_controller_recv_event(handle, types_json, timeout_secs, out_event_json) → i32 (0/-1/-2/-3)
• mesh_job_proxy_send_event(handle, event_type, payload_json, out_receipt_json) → i32 (0/-1/-2/-3/-4) — distinct codes for JobNotFound vs JobTerminal
• parse_ffi_timeout_secs helper: rejects NaN/±Inf, uses Duration::try_from_secs_f64 for overflow, negative-sentinel < 0 convention for "no timeout"

Java SDK (src/runtime/java/mcp-mesh-sdk/)

• JobController.recvEvent(List<String> types, Duration timeout) returning Map<String, Object> (event) or null (timeout)
• JobProxy.sendEvent(String eventType, Map<String, Object> payload) returning receipt Map
• New MeshJobs.postEvent(jobId, eventType, payload) static helper — LRU-bounded JobProxy cache (default 256, env override MCP_MESH_JOBPROXY_CACHE_MAX) using LinkedHashMap(accessOrder=true) with explicit synchronized blocks
• JobNotFoundException and JobTerminalException new typed exceptions extending the existing MeshException parent

Tests

• Rust FFI: +6 unit tests (jobs_ffi: 16 → 22)
• Java unit: +19 tests across MeshJobsTest and JobEventApiTest (sdk: 42 → 61; full Java module: 124 tests pass)
• Integration suite uc23_meshjob_java: 3 new test cases mirroring Python tc24/25/26 and TS tc24/25/26_ts:
  • tc24_event_injection_happy_path_java
  • tc25_event_type_filter_java
  • tc26_cancel_posts_synthetic_event_java
  • Reuses existing long-task-provider-java / long-task-consumer-java fixtures with 3 new tools each
  • Baseline 23 + new 3 = 26/26 pass

Public API parity matrix (3 runtimes)

API	Java	TypeScript	Python
Producer wait for event	job.recvEvent(types, duration)	job.recvEvent(types, timeoutSecs)	job.recv_event(types, timeout_secs)
Consumer post to specific proxy	proxy.sendEvent(type, payload)	proxy.sendEvent(type, payload)	proxy.send_event(type, payload)
Convenience helper	MeshJobs.postEvent(...)	mesh.jobs.postEvent(...)	mesh.jobs.post_event(...)
Typed errors	JobNotFoundException / JobTerminalException	JobNotFoundError / JobTerminalError	JobNotFoundError / JobTerminalError
Proxy cache cap	MCP_MESH_JOBPROXY_CACHE_MAX (256)	same	same
Cancel synthetic event grace	Server-side (200ms, MCP_MESH_CANCEL_EVENT_GRACE_MS) — no client change needed

Acceptance criteria

• Rust FFI tests: baseline + 6 new pass
• Java unit tests: baseline + 19 new pass
• tsuite run --uc uc23_meshjob_java → 26/26 (23 baseline + 3 new)
• mcp-mesh-core JNR-FFI loads cleanly with the 2 new symbols

Related

• MeshJob: event injection into running jobs — recv_event + send_event + Stream subscription + trace propagation #1032 — original epic
• MeshJob: consumer-pushed events into running jobs (recv_event/send_event) #1041 — Python vertical (merged)
• ts: MeshJob event injection parity — recvEvent/sendEvent/postEvent #1043 — TypeScript vertical (merged)