Joan a 23:33, 12 oct 2009

2009-10-12T23:33:39Z

Pàgina nova

*http://www.javaworld.com/jw-12-1996/jw-12-sockets.html

Faig una aplicació molt simple de servidor d'echos, per veure com el client envia ''Hola Joan'', ho rep el servidor, ho reenvia al client, i el client mostra el missatge que ha rebut del servidor.

Proj14: classe EchoServer
<pre>
import java.io.*;
import java.net.*;
public class EchoServer {
public static void main(String args[]) {
// declaration section:
// declare a server socket and a client socket for the server
// declare an input and an output stream
ServerSocket echoServer = null;
String line;
DataInputStream is;
PrintStream os;
Socket clientSocket = null;
// Try to open a server socket on port 9999
// Note that we can't choose a port less than 1023 if we are not
// privileged users (root)
try {
echoServer = new ServerSocket(9999);
}
catch (IOException e) {
System.out.println(e);
}
// Create a socket object from the ServerSocket to listen and accept
// connections.
// Open input and output streams
try {
clientSocket = echoServer.accept();
is = new DataInputStream(clientSocket.getInputStream());
os = new PrintStream(clientSocket.getOutputStream());
// As long as we receive data, echo that data back to the client.
while (true) {
line = is.readLine();
os.println(line);
}
}
catch (IOException e) {
System.out.println(e);
}
}
}
</pre>

Proj15: classe EchoClient
<pre>
import java.io.*;
import java.net.*;
public class EchoClient {
public static void main(String[] args) {
// declaration section:
// smtpClient: our client socket
// os: output stream
// is: input stream
Socket smtpSocket = null;
DataOutputStream os = null;
DataInputStream is = null;
// Initialization section:
// Try to open a socket on port 25
// Try to open input and output streams
try {
smtpSocket = new Socket("192.168.1.35", 9999);
os = new DataOutputStream(smtpSocket.getOutputStream());
is = new DataInputStream(smtpSocket.getInputStream());
} catch (UnknownHostException e) {
System.err.println("Don't know about host: 192.168.1.35");
} catch (IOException e) {
System.err.println("Couldn't get I/O for the connection to: hostname");
}
// If everything has been initialized then we want to write some data
// to the socket we have opened a connection to on port 25
if (smtpSocket != null && os != null && is != null) {
try {
// The capital string before each colon has a special meaning to SMTP
// you may want to read the SMTP specification, RFC1822/3
os.writeBytes("Hola Joan\n");
os.writeBytes("QUIT");
// keep on reading from/to the socket till we receive the "Ok" from SMTP,
// once we received that then we want to break.
String responseLine;
while ((responseLine = is.readLine()) != null) {
System.out.println("Server: " + responseLine);
if (responseLine.indexOf("Ok") != -1) {
break;
}
}
// clean up:
// close the output stream
// close the input stream
// close the socket
os.close();
is.close();
smtpSocket.close();
} catch (UnknownHostException e) {
System.err.println("Trying to connect to unknown host: " + e);
} catch (IOException e) {
System.err.println("IOException: " + e);
}
}
}
}

</pre>

La idea és que ara la part de client la puc fer amb Android. Més tard, la part de servidor la puc integrar en un projecte Java-Misishare, i d'aquesta manera puc aconseguir fer que el Android sigui un controlador midi.

Programació de sockets amb Java - Historial de revisió

Joan a 23:33, 12 oct 2009