What are the best practices for exceptions over remote methods?
I’m sure that you need to handle all exceptions at the level of a remote method implementation, because you need to log it on the server side. But what should you do afterwards?
Should you wrap the exception in a RemoteException (java) and throw it to the client? This would mean that the client would have to import all exceptions that could be thrown. Would it be better to throw a new custom exception with fewer details? Because the client won’t need to know all the details of what went wrong. What should you log on the client? I’ve even heard of using return codes(for efficiency maybe?) to tell the caller about what happened.
The important thing to keep in mind, is that the client must be informed of what went wrong. A generic answer of “Something failed” or no notification at all is unacceptable. And what about runtime (unchecked) exceptions?
Here’s what I did. Every Remote Method implementation catches all Exceptions on the server side and logs them. Then they are wrapped in a Custom Exception, which will contain a description of the problem. This description must be useful to the client, so it won’t contain all the details of the caught Exception, because the client doesn’t need them. They have already been logged on the server side. Now, on the client, these Exceptions can be handled how the user wishes.
Why I chose using Exceptions and not return codes is because of one very important drawback of return codes: you can’t throw them to higher levels without some effort. This means you have to check for an error right after the call and handle it there. But this may not be what I want.