Win a copy of Cross-Platform Desktop Applications: Using Node, Electron, and NW.js this week in the JavaScript forum!
  • Post Reply Bookmark Topic Watch Topic
  • New Topic

Applet-Sockets(Plz help me out)  RSS feed

 
Angela Jessi
Ranch Hand
Posts: 428
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi all,
I want to know following:
I have an applet which has socket listener and socket sender. Here is my code:

import java.awt.*;
import java.net.*;
import java.io.*;
import java.lang.*;
import java.applet.*;
import java.util.*;
import java.awt.event.*;
public class K_ClientSocket1 extends Applet implements ActionListener{
public TextArea ta;
private Button send;
private Button rcv;
public String g;
Socket localSocket;
PrintWriter out;
int Port = 11200;
//String IpAddr = "10.3.158.172";
int localPort;
//char []buffer = new char[4000];

public void init() {
//create GUI's
Panel p = new Panel();
p.setLayout(new FlowLayout());
ta = new TextArea();
p.add(ta);
add(p,"North");
send = new Button("Send Message");
send.addActionListener(this);
rcv = new Button("Listener");
rcv.addActionListener(this);
Panel p1 = new Panel();
p1.setLayout(new FlowLayout());
p1.add(send);
p1.add(rcv);
add(p1,"Center");
}

public void actionPerformed(ActionEvent e) {
if(e.getSource() == send)
{
//Send Data
try {
localSocket = new Socket(InetAddress.getLocalHost(),Port);
localPort = localSocket.getLocalPort();
String s = "Message:Konica Client";
//Setup data stream in and out of socket
out= new PrintWriter(localSocket.getOutputStream());
//send signature to server
out.println(s);
out.flush();
out.close();
localSocket.close();
}
catch(UnknownHostException uh)
{
System.out.println("Unknown Host Exception");
}
catch (IOException ioe)
{
System.out.println("Input/output Exception");
}
}
if(e.getSource() == rcv)
{
//declaration
ServerSocket echoServer = null;
Socket clientSocket = null;
BufferedReader in;
String g;
int sPort;
sPort = localPort;
try
{
echoServer = new ServerSocket(sPort);
clientSocket = echoServer.accept();
in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream( )));
// while socket open
while ((in.readLine())!= null)
{
g = in.readLine();
ta.appendText(g);
}
clientSocket.close();
}
catch (IOException ioe)
{
System.out.println("Input/output error");
}
}
}
}
When I try to send to server, i can able to send. But when i try to listen or receive from the server i am getting following errors:
com.ms.security.SecurityExceptionEx[K_ClientSocket1.init]: cannot access 7689
at com/ms/security/permissions/NetIOPermission.check (NetIOPermission.java)
at com/ms/security/PolicyEngine.deepCheck (PolicyEngine.java)
at com/ms/security/PolicyEngine.checkPermission (PolicyEngine.java)
at com/ms/security/StandardSecurityManager.chk (StandardSecurityManager.java)
at com/ms/security/StandardSecurityManager.checkListen (StandardSecurityManager.java)
at java/net/ServerSocket.<init> (ServerSocket.java)
at java/net/ServerSocket.<init> (ServerSocket.java)
at K_ClientSocket1.init (K_ClientSocket1.java:73)
at com/ms/applet/AppletPanel.securedCall0 (AppletPanel.java)
at com/ms/applet/AppletPanel.securedCall (AppletPanel.java)
at com/ms/applet/AppletPanel.processSentEvent (AppletPanel.java)
at com/ms/applet/AppletPanel.processSentEvent (AppletPanel.java)
at com/ms/applet/AppletPanel.run (AppletPanel.java)
at java/lang/Thread.run (Thread.java)
Please let me know,
Thanks,
angela
 
maateen ashraf
Ranch Hand
Posts: 122
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
ok, Angela Jessi
now u r getting these exceptions because the VM of browser have security policy which doesn't let applet to write on the socket
so u have two solutions
either u have to make ur applet signed
or
to change the security policy of VM
tell me in detail what u actually want
ok
bye
 
Angela Jessi
Ranch Hand
Posts: 428
  • Mark post as helpful
  • send pies
  • Quote
  • Report post to moderator
Hi Maaten,
Actually Ihave project. I have to develop client side.I have to open the socket and get the value from Printer and update it in my applet.
So I opened the socket with applet. As you know I am getting above errors. Which is the easiest way to make it either to go for signed applet and to change the security policy of VM
I really appreciate your help,
Thanks again,
Plz let me know
Angela
 
  • Post Reply Bookmark Topic Watch Topic
  • New Topic
Boost this thread!