Java Reference
In-Depth Information
Example 5•9: Server.java (continued)
}
/**
* A Listener is a Thread, and this is its body.
* Wait for connection requests, accept them, and pass the socket on
* to the addConnection method of the server.
**/
public void run() {
while(!stop) {
// loop until we're asked to stop.
try {
Socket client = listen_socket.accept();
addConnection(client, service);
}
catch (InterruptedIOException e) {}
catch (IOException e) {log(e);}
}
}
}
/**
* This is the method that Listener objects call when they accept a
* connection from a client. It either creates a Connection object
* for the connection and adds it to the list of current connections,
* or, if the limit on connections has been reached, it closes the
* connection.
**/
protected synchronized void addConnection(Socket s, Service service) {
// If the connection limit has been reached
if (connections.size() >= maxConnections) {
try {
// Then tell the client it is being rejected.
PrintWriter out = new PrintWriter(s.getOutputStream());
out.print("Connection refused; " +
"the server is busy; please try again later.\n");
out.flush();
// And close the connection to the rejected client.
s.close();
// And log it, of course
log("Connection refused to " +
s.getInetAddress().getHostAddress() +
":" + s.getPort() + ": max connections reached.");
} catch (IOException e) {log(e);}
}
else { // Otherwise, if the limit has not been reached
// Create a Connection thread to handle this connection
Connection c = new Connection(s, service);
// Add it to the list of current connections
connections.add(c);
// Log this new connection
log("Connected to " + s.getInetAddress().getHostAddress() +
":" + s.getPort() + " on port " + s.getLocalPort() +
" for service " + service.getClass().getName());
// And start the Connection thread to provide the service
c.start();
}
}
/**
