Objects running on threads

Question

Hi everyone,
I have an engine that I have coded that provides a set of services to various applications. Currently the engine is single-threaded, meaning that if more than one person where to access the same instance of the engine there would be shared data violations. I'm sure that you know the drill...
So, I am about the add a "UserSpace" class to the engine. Each person that logs into the engine will be assigned a user space, within which is stored information that is pertinent to them (and is isolated from all other users).
I am familiar with using threads to perform lengthy operations (ie: making an object Runnable and calling the start() method to get things going). But I have never used threads in this way before.
What I mean is that I want to be able to assign a thread to each user space. In other words every user will have their own unique thread just for them. Method calls on the user space do not need to be synchronized because the information within them is, by definition, not shared. If the user space has to make calls to other areas of the engine then those methods would have to be synchronized but I can deal with that.
So how would I go about accomplishing this? Is it just a case of implementing Runnable as I normally do, calling start() and then make method calls?
Thanks in advance for your help. :)
Ben

Answer 1

I believe you could accomplish what you wish w/3 classes. In accordance with your example and subsequent explanation, they are as follows:
public class UserSpace {
private Object mDataThatIsNotShared; // etc.
public String methodOne() { /*some code */ }
public void methodTwo(String s) { /*some code */ }
public class Server {
// This class would accept socket connections. For each socket
// connection accepted, create an object of the third class called
// ServerThread (see below):
while (true) {
// The line below blocks until connection:
Socket socketAccepted=serverSocket.accept();
ServerThread srvrThrd=new ServerThread(socketAccepted);
srvrThrd.start();
public class ServerThread extends Thread {
private Socket mSocket;
private UserSpace userSpace;
ServerThread(Socket socket) {
mSocket=socket;
userSpace=new UserSpace(...); //See, each ServerThread owns its own
public void run() {
// Do whatever work you want w/UserSpace.
Of course, this is way overly simplistic...Does not take into account the fact that you could have unlimited threads...i.e., your Server class needs to implement some sort of thread pool, etc.
Does this help you?
--Mike