prompt: We are currently solving the following issue within our repository. Here is the issue text:
  --- BEGIN ISSUE ---
  Make the multi-worker feature for Java worker experimental
  Right now, the multi-worker feature for Java worker is enabled by default, but the `ActorHandle::kill()` API doesn't work well if multi-worker is enabled because it will kill the whole process instead of one worker in the process.
  
  To avoid complaints from Java users, we should disable the multi-worker feature by default, but we still enable it in unit test.
  
  --- END ISSUE ---
  
  Below are some code segments, each from a relevant file. One or more of these files may contain bugs.
  --- BEGIN FILES ---
  Path: `python/ray/job_config.py`
  Content:
  ```
  1 import ray
  2 
  3 
  4 class JobConfig:
  5     """A class used to store the configurations of a job.
  6 
  7     Attributes:
  8         worker_env (dict): Environment variables to be set on worker
  9             processes.
  10         num_java_workers_per_process (int): The number of java workers per
  11             worker process.
  12         jvm_options (str[]): The jvm options for java workers of the job.
  13     """
  14 
  15     def __init__(
  16             self,
  17             worker_env=None,
  18             num_java_workers_per_process=10,
  19             jvm_options=None,
  20     ):
  21         if worker_env is None:
  22             self.worker_env = dict()
  23         else:
  24             self.worker_env = worker_env
  25         self.num_java_workers_per_process = num_java_workers_per_process
  26         if jvm_options is None:
  27             self.jvm_options = []
  28         else:
  29             self.jvm_options = jvm_options
  30 
  31     def serialize(self):
  32         job_config = ray.gcs_utils.JobConfig()
  33         for key in self.worker_env:
  34             job_config.worker_env[key] = self.worker_env[key]
  35         job_config.num_java_workers_per_process = (
  36             self.num_java_workers_per_process)
  37         job_config.jvm_options.extend(self.jvm_options)
  38         return job_config.SerializeToString()
  39
  ```
  --- END FILES ---
  
  Please first localize the bug based on the issue statement, and then generate a patch according to the `git diff` format fenced by three backticks.
  
  Here is an example:
  
  ```diff
  diff --git a/examples/server_async.py b/examples/server_async.py
  --- a/examples/server_async.py
  +++ b/examples/server_async.py
  @@ -313,4 +313,4 @@
   
   
   if __name__ == "__main__":
  -    asyncio.run(run_async_server("."), debug=True)
  +    asyncio.run(run_async_server(), debug=True)
  diff --git a/examples/server_sync.py b/examples/server_sync.py
  --- a/examples/server_sync.py
  +++ b/examples/server_sync.py
  @@ -313,5 +313,5 @@
   
   
   if __name__ == "__main__":
  -    server = run_sync_server(".")
  +    server = run_sync_server()
       server.shutdown()
  
  ```
  
golden_diff: diff --git a/python/ray/job_config.py b/python/ray/job_config.py
  --- a/python/ray/job_config.py
  +++ b/python/ray/job_config.py
  @@ -15,7 +15,7 @@
       def __init__(
               self,
               worker_env=None,
  -            num_java_workers_per_process=10,
  +            num_java_workers_per_process=1,
               jvm_options=None,
       ):
           if worker_env is None:
  
verification_info: {"golden_diff": "diff --git a/python/ray/job_config.py b/python/ray/job_config.py\n--- a/python/ray/job_config.py\n+++ b/python/ray/job_config.py\n@@ -15,7 +15,7 @@\n     def __init__(\n             self,\n             worker_env=None,\n-            num_java_workers_per_process=10,\n+            num_java_workers_per_process=1,\n             jvm_options=None,\n     ):\n         if worker_env is None:\n", "issue": "Make the multi-worker feature for Java worker experimental\nRight now, the multi-worker feature for Java worker is enabled by default, but the `ActorHandle::kill()` API doesn't work well if multi-worker is enabled because it will kill the whole process instead of one worker in the process.\r\n\r\nTo avoid complaints from Java users, we should disable the multi-worker feature by default, but we still enable it in unit test.\n", "before_files": [{"content": "import ray\n\n\nclass JobConfig:\n    \"\"\"A class used to store the configurations of a job.\n\n    Attributes:\n        worker_env (dict): Environment variables to be set on worker\n            processes.\n        num_java_workers_per_process (int): The number of java workers per\n            worker process.\n        jvm_options (str[]): The jvm options for java workers of the job.\n    \"\"\"\n\n    def __init__(\n            self,\n            worker_env=None,\n            num_java_workers_per_process=10,\n            jvm_options=None,\n    ):\n        if worker_env is None:\n            self.worker_env = dict()\n        else:\n            self.worker_env = worker_env\n        self.num_java_workers_per_process = num_java_workers_per_process\n        if jvm_options is None:\n            self.jvm_options = []\n        else:\n            self.jvm_options = jvm_options\n\n    def serialize(self):\n        job_config = ray.gcs_utils.JobConfig()\n        for key in self.worker_env:\n            job_config.worker_env[key] = self.worker_env[key]\n        job_config.num_java_workers_per_process = (\n            self.num_java_workers_per_process)\n        job_config.jvm_options.extend(self.jvm_options)\n        return job_config.SerializeToString()\n", "path": "python/ray/job_config.py"}], "after_files": [{"content": "import ray\n\n\nclass JobConfig:\n    \"\"\"A class used to store the configurations of a job.\n\n    Attributes:\n        worker_env (dict): Environment variables to be set on worker\n            processes.\n        num_java_workers_per_process (int): The number of java workers per\n            worker process.\n        jvm_options (str[]): The jvm options for java workers of the job.\n    \"\"\"\n\n    def __init__(\n            self,\n            worker_env=None,\n            num_java_workers_per_process=1,\n            jvm_options=None,\n    ):\n        if worker_env is None:\n            self.worker_env = dict()\n        else:\n            self.worker_env = worker_env\n        self.num_java_workers_per_process = num_java_workers_per_process\n        if jvm_options is None:\n            self.jvm_options = []\n        else:\n            self.jvm_options = jvm_options\n\n    def serialize(self):\n        job_config = ray.gcs_utils.JobConfig()\n        for key in self.worker_env:\n            job_config.worker_env[key] = self.worker_env[key]\n        job_config.num_java_workers_per_process = (\n            self.num_java_workers_per_process)\n        job_config.jvm_options.extend(self.jvm_options)\n        return job_config.SerializeToString()\n", "path": "python/ray/job_config.py"}]}