Java Language Remote Method Invocation (RMI) Client-Server: invoking methods in one JVM from another
Example
The shared remote interface:
package remote;
import java.rmi.Remote;
import java.rmi.RemoteException;
public interface RemoteServer extends Remote {
int stringToInt(String string) throws RemoteException;
}
The server implementing the shared remote interface:
package server;
import java.rmi.RemoteException;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
import java.rmi.server.UnicastRemoteObject;
import remote.RemoteServer;
public class Server implements RemoteServer {
@Override
public int stringToInt(String string) throws RemoteException {
System.out.println("Server received: \"" + string + "\"");
return Integer.parseInt(string);
}
public static void main(String[] args) {
try {
Registry reg = LocateRegistry.createRegistry(Registry.REGISTRY_PORT);
Server server = new Server();
UnicastRemoteObject.exportObject(server, Registry.REGISTRY_PORT);
reg.rebind("ServerName", server);
} catch (RemoteException e) {
e.printStackTrace();
}
}
}
The client invoking a method on the server (remotely):
package client;
import java.rmi.NotBoundException;
import java.rmi.RemoteException;
import java.rmi.registry.LocateRegistry;
import java.rmi.registry.Registry;
import remote.RemoteServer;
public class Client {
static RemoteServer server;
public static void main(String[] args) {
try {
Registry reg = LocateRegistry.getRegistry();
server = (RemoteServer) reg.lookup("ServerName");
} catch (RemoteException | NotBoundException e) {
e.printStackTrace();
}
Client client = new Client();
client.callServer();
}
void callServer() {
try {
int i = server.stringToInt("120");
System.out.println("Client received: " + i);
} catch (RemoteException e) {
e.printStackTrace();
}
}
}
Output:
Server received: "120"
Client received: 120
