I've been working on different ways to do this for 2 full coding days, i need some help:
I want to create a multiplayer game in java online. To do this i need communication between the server and the applet
I was under the impression that as long as the UDP server is being ran on the same machine the applet is being hosted on, it would work. (perhaps i need to be corrected on that)
I continually get this error on the error console (from applet) java.security.AccessControlException: access denied (java.net.SocketPermission 127.0.0.1:5556 connect,resolve)
When trying to receive messages on the applet, nothing happens, nothing is sent and nothing is received (the udp server is sending a message,applet is not receiving, i know the udp is sending correctly as i tested separately it with a client)
Here is the UDPclient.java applet:
``
import java.io.*;
import java.net.*;
import java.applet.*;
public class UDPClient extends Applet
{
protected DatagramSocket socket = null;
protected DatagramPacket packet = null;
String ipAddress;
public void init()
{
try{
System.out.println("got username");
String username = getParameter("username");
System.out.println("got ip");
ipAddress = getParameter("ip");
System.out.println("makingsocket");
socket = new DatagramSocket();
System.out.println("sending packet");
sendPacket();
System.out.println("receiving packet");
receivePacket();
System.out.println("closing socket");
socket.close();
}catch(Exception e){e.printStackTrace();}
}
public void sendPacket() throws IOException
{
byte[] buf ="hihihi".getBytes(); // send hihihi
InetAddress address = InetAddress.getByName(ipAddress);
packet = new DatagramPacket(buf, buf.length, address, 5556);
System.out.println("sending packet");
socket.send(packet);
int port = packet.getPort();
}
public void receivePacket() throws IOException
{
byte[] buf = new byte[256];
packet = new DatagramPacket(buf, buf.length);
System.out.println("getting packet--- calling socket.receive");
socket.receive(packet);
System.out.println("got here, receiving packet");
String modifiedSentence =new String(packet.getData());
System.out.println("FROM SERVER:" + modifiedSentence);
}
}
Here is the HTML file i run the applet with:
<applet code="UDPClient.class" width="640" height="480">
<param name="username" value="Guest">
<param name="ip" value="localhost">
</applet>
And here is the server i'm using
import java.io.*;
import java.net.*;
public class multiTest
{
static protected DatagramSocket socket = null;
static protected DatagramPacket packet = null;
public static void main(String [] args) throws IOException
{
socket = new DatagramSocket(5556);
while(true)
{
receivePacket();
sendPacket();
}
}
public static void receivePacket() throws IOException
{
//receive message from client
byte[] buf = new byte[256];
packet = new DatagramPacket(buf, buf.length);
socket.receive(packet);
//translate message in a thread
String message = new String(packet.getData(), 0, packet.getLength());
System.out.println("received" + message);
// should really make thread;
}
public static void sendPacket() throws IOException
{
byte[] buf = "ack".getBytes();
//send the message to the client to the given address and port
InetAddress address = packet.getAddress();
int port = packet.getPort();
packet = new DatagramPacket(buf, buf.length, address, port);
socket.send(packet);
}
}
I have been trying to follow the tutorial here :http://corvstudios.com/tutorials/udpMultiplayer.php to create this code.
i really didnt wanna have to end up using MINA, Tomcat or install any network framework - but if i have to let me know, it'll save me a lot of time
Any help is sincerely appreciated in advanced!
