import java.rmi.*;
public interface DShared<Resource extends java.io.Serializable> extends Remote
{
    // status indicators: all non-blocking:
    int capacity() throws RemoteException;
    int waiting() throws RemoteException;   
    int busy() throws RemoteException;      
    int empty() throws RemoteException;     

    // produces resource, blocks if empty()<1, returns id uniquely identifying
    // this resource as part of the pool:
    int produce(Resource R) throws RemoteException;

    // Attempt to consume resource, blocks if none are available, returns
    // resource id, which can be acquired by get.
    int consume() throws RemoteException; //, InterruptedException;;    

    // when finished with resource, call  (non-blocking)
    void finished(int rid) throws RemoteException;

    // returns resource indicated by resource id, returns null if not valid.
    // this is always a non-blocking call.
    Resource getresource(int rid) throws RemoteException;

    // blocks calling thread until all resources in pool have been consumed
    // (finished).  returns total number of resources consumed in life time of
    // resource pool.
    int joinall()throws RemoteException;
}

// shared by server and client