JExposer

Java Agent that allows gaining access to JavaClasses' public methods via JSON-RPC 2.0 protocol on the specified socket.

How to use

Simply insert

-javaagent:path/to/jexposer.jar=class.you.want.to.be.Accessed@<port>

before the –jar parameter of your java command, then start sending requests via the specified socket port. Every instance of the class is treated as a distinct JSON-RPC server. Note that the agent does not interfere with *.class files on the disk.

Built-in methods

As pointed out in JSON-RPC 2.0 specification, using method names prefixed by rpc is highly discouraged. If the method field of a sent request is one of the following and the method is listed in the target class, the response will not be sent and the corresponding operation will be performed.

1. rpcShutdown -- shuts down the server and the server's thread
2. rpcSwitchSync -- switches method invocation to synchronous mode (default), meaning that the server will not start parsing a new message before it responds to the ongoing request.
3. rpcSwitchAsync -- switches method invocation to asynchronous mode, meaning that the invocations could be executed in parallel (default parallelism is 4).

Configuration

Certain properties could be specified

• -Djexposer.parallelism is the number of ForkJoinPool parallelism to process the async invocations. The default number is 4.
• -Djexposer.thread.daemon specifies whether the agent dies with an application or not. The default value is true.
• -Djexposer.thread.name agent's thread name. The resulting name will be JSON-RPC@<specified name>. The default name is the fully qualified class name.
• -Djexposer.thread.priority defines the agent's thread priority. The default value is 5.