How do I solve this indexOutOfBoundsException in my server send/receive thread?
- by Stefan Schouten
I am creating a multiplayer game in Java with a server and multiple clients. Everything runs perfectly, until I press the Kick-button in the server to kick a client.
Error at receive thread of server, after kicking the first person who joined out of three:
java.lang.IndexOutOfBoundsException: Index: 2, Size: 2
at java.util.ArrayList.rangeCheck(ArrayList.java:604)
at java.util.ArrayList.get(ArrayList.java:382)
> at networktest.Server$3.run(Server.java:186)
at java.lang.Thread.run(Thread.java:722)
The pointed line is the ois = new ObjectInputStream where I send datatype. The server kicks the first person perfectly, but removes the second one in the list too, with an error of java.lang.ClassCastException.
server receive:
private static Thread receive = new Thread()
{
@Override
public void run()
{
ObjectInputStream ois;
while (true)
{
for (int i = 0; i < list_sockets.size(); i++)
{
try
{
ois = new ObjectInputStream(list_sockets.get(i).getInputStream());
int receive_state = (Integer) ois.readObject(); // receive state
ois = new ObjectInputStream(list_sockets.get(i).getInputStream());
byte datatype = (byte) ois.readObject(); // receive datatype
if(datatype == 2){
ois = new ObjectInputStream(list_sockets.get(i).getInputStream());
ChatLine chatLine = (ChatLine) ois.readObject(); // receive ChatLine
} else if (datatype == 0){
ois = new ObjectInputStream(list_sockets.get(i).getInputStream());
DataPackage dp = (DataPackage) ois.readObject(); // receive dp
list_data.set(i, dp);
}
if (receive_state == 1) // Client Disconnected by User
{
disconnectClient(i);
i--;
}
}
catch (Exception ex) // Client Disconnected (Client Didn't Notify Server About Disconnecting)
{
System.err.println("Error @ receive:");
ex.printStackTrace();
disconnectClient(i);
i--;
}
}
try {
this.sleep(3);
} catch (InterruptedException ex) {
Logger.getLogger(Server.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
};
user send:
Thread send = new Thread()
{
public void run()
{
ObjectOutputStream oos;
byte datatype = 0;
while (connected){
if (socket != null){
try {
DataPackage dp = new DataPackage();
dp.x = Client.player.x;
dp.y = Client.player.y;
dp.username = username;
dp.charType = charType;
dp.walking = (byte)Client.player.walking;
if (Client.outputChatLine.line != null)
datatype = 2;
else {
datatype = 0;
}
oos = new ObjectOutputStream(socket.getOutputStream());
oos.writeObject(Integer.valueOf(Client.this.state)); // send state
oos = new ObjectOutputStream(socket.getOutputStream());
oos.writeObject(Byte.valueOf(datatype)); // send datatype
if (datatype == 2)
{
oos.reset();
oos.writeObject(Client.outputChatLine);
Client.outputChatLine = new ChatLine();
} else {
oos = new ObjectOutputStream(socket.getOutputStream());
oos.writeObject(dp);
}
if (Client.this.state == 1) {
connected = false;
socket = null;
JOptionPane.showMessageDialog(null, "Client Disconnected", "Info", 1);
System.exit(0);
}
}
catch (Exception ex){}
}
try {
this.sleep(2);
} catch (InterruptedException ex) {
Logger.getLogger(Client.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
};
disconnect client method:
public static void disconnectClient(int index)
{
try
{
list_clients_model.removeElementAt(index);
list_client_states.remove(index);
list_data.remove(index);
list_sockets.remove(index);
}
catch (Exception ex) {}
}
Does anyone know how to solve this?
