Storage emulator shows WARNING: sun.misc.Unsafe::arrayBaseOffset on Java 24 #9623
Description
[REQUIRED] Environment info
firebase-tools: v15.0.0
Platform: macOS
Java: v24
[REQUIRED] Test case
See "Steps to reproduce"
[REQUIRED] Steps to reproduce
- Run
firebase init storage- Please select an option: Don't set up a default project
- What file should be used for Storage Rules? storage.rules
- Run
firebase emulators:start --project demo-project
[REQUIRED] Expected behavior
No waning message when starting the emulators
$ java --version
openjdk 22.0.2 2024-07-16
OpenJDK Runtime Environment Zulu22.32+15-CA (build 22.0.2+9)
OpenJDK 64-Bit Server VM Zulu22.32+15-CA (build 22.0.2+9, mixed mode, sharing)
$ firebase emulators:start --project demo-project
i emulators: Starting emulators: storage
i emulators: Detected demo project ID "demo-project", emulated services will use a demo configuration and attempts to access non-emulated services for this project will fail.
┌─────────────────────────────────────────────────────────────┐
│ ✔ All emulators ready! It is now safe to connect your app. │
│ i View Emulator UI at http://127.0.0.1:4000/ │
└─────────────────────────────────────────────────────────────┘
┌──────────┬────────────────┬───────────────────────────────┐
│ Emulator │ Host:Port │ View in Emulator UI │
├──────────┼────────────────┼───────────────────────────────┤
│ Storage │ 127.0.0.1:9199 │ http://127.0.0.1:4000/storage │
└──────────┴────────────────┴───────────────────────────────┘
Emulator Hub host: 127.0.0.1 port: 4400
Other reserved ports: 4500
Issues? Report them at https://github.com/firebase/firebase-tools/issues and attach the *-debug.log files.
[REQUIRED] Actual behavior
Warning message when starting the emulator WARNING: sun.misc.Unsafe::arrayBaseOffset has been called by com.google.protobuf.UnsafeUtil$MemoryAccessor
$ java --version
openjdk 24.0.2 2025-07-15
OpenJDK Runtime Environment Zulu24.32+13-CA (build 24.0.2+12)
OpenJDK 64-Bit Server VM Zulu24.32+13-CA (build 24.0.2+12, mixed mode, sharing)
$ firebase emulators:start --project demo-project
i emulators: Starting emulators: storage
i emulators: Detected demo project ID "demo-project", emulated services will use a demo configuration and attempts to access non-emulated services for this project will fail.
⚠ Unexpected rules runtime error: WARNING: A terminally deprecated method in sun.misc.Unsafe has been called
WARNING: sun.misc.Unsafe::arrayBaseOffset has been called by com.google.protobuf.UnsafeUtil$MemoryAccessor (file:/Users/alejandromarco/.cache/firebase/emulators/cloud-storage-rules-runtime-v1.1.3.jar)
WARNING: Please consider reporting this to the maintainers of class com.google.protobuf.UnsafeUtil$MemoryAccessor
WARNING: sun.misc.Unsafe::arrayBaseOffset will be removed in a future release
┌─────────────────────────────────────────────────────────────┐
│ ✔ All emulators ready! It is now safe to connect your app. │
│ i View Emulator UI at http://127.0.0.1:4000/ │
└─────────────────────────────────────────────────────────────┘
┌──────────┬────────────────┬───────────────────────────────┐
│ Emulator │ Host:Port │ View in Emulator UI │
├──────────┼────────────────┼───────────────────────────────┤
│ Storage │ 127.0.0.1:9199 │ http://127.0.0.1:4000/storage │
└──────────┴────────────────┴───────────────────────────────┘
Emulator Hub host: 127.0.0.1 port: 4400
Other reserved ports: 4500
Issues? Report them at https://github.com/firebase/firebase-tools/issues and attach the *-debug.log files.
Notes
This occurs on Java 24, no warning messages are shown on Java 22
AFAICT, the storage emulator works without any issues even with the warning message