Applet socket connection

Hi,
I have an applet that connects to a server java console program through a socket connection which works fine from the command line using appletviewer but doesn't work when running in a html page. The applet is not signed however because the applet and server are running on the same machine it shouldn't need to be. I have used socket connections in applets before and have managed to make the connection to server without having it signed but this one is not working for some reason. I have checked the port is opened and again its the same one I have used before so I know its open.
I am getting the message java.security.AccessControlException: access denied (java.net.SocketPermission 127.0.0.1:5000 connect,resolve) when calling:
Socket s = new Socket(ip,port);I also have a java.policy.applet file in the project root directory which has the following in:
grant {
permission java.security.AllPermission;
};Does anyone know a reason why access could be restricted?

Night.Monkey wrote:
Hi,
I have an applet that connects to a server java console program through a socket connection which works fine from the command line using appletviewer but doesn't work when running in a html page. The applet is not signed however because the applet and server are running on the same machine it shouldn't need to be.Wrong. An unsigned applet can only connect back to the server from where it was downloaded. Your applet comes from www.javawebgames.co.uk and tries to connect to 127.0.0.1.
Would your server be at www.javawebgames.co.uk there should be no problem.
I also have a java.policy.applet file in the project root directory which has the following in:
grant {
permission java.security.AllPermission;
};I think this should have zero effect when you are running in the actual browser.

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Applet socket connect behaves wrong.

Hi,
I have a very strange behavior from the Socket connect method. When i run the code attached as an applet the connect returns as if the connection is established (no machine on my network with the address 12.12.12.12 and ping to 12.12.12.12 fails as expected).
When i run it from a command line (in a stadard main) the connect behaves as expected an i get an exception.
Any ideas? what am i doing wrong? (or is it a known applet behavior???)
thanks...
===========================================================
the code:
===========================================================
public void start() {
SocketAddress sockaddr = new InetSocketAddress("12.12.12.12", 16000);
Socket sock = new Socket();
try {
System.out.println("Start conn 1");
sock.connect(sockaddr, 3000);
} catch (IOException e) {
System.out.println("Connect failed");
e.printStackTrace();
return;
if (sock.isConnected()) {
System.out.println("Connected");
System.out.println("Connect succ 1");
Edited by: ohad_atia on Jun 28, 2009 12:25 AM

here is the applet start code - the rest of the methods are empty:
(no exception here - that is the problem)
      public void start() {
          SocketAddress sockaddr = new InetSocketAddress("12.12.12.12", 16000);
                 Socket sock = new Socket();
          try {
               System.out.println("Start conn 1");
               sock.connect(sockaddr, 3000);
          } catch (IOException e) {
               System.out.println("Connect failed");
              e.printStackTrace();
              return;
          if (sock.isConnected()) {
             System.out.println("Connected");
          System.out.println("Connect succ 1");
      }the code and output i got when i run it using a command line:
import java.net.Socket;
import java.net.SocketAddress;
import java.net.InetSocketAddress;
import java.io.IOException;
public class networktest {
        public static void main(String[] argv) {
                SocketAddress sockaddr = new InetSocketAddress("12.12.12.12", 16000);
                Socket sock = new Socket();
        try {
                sock.connect(sockaddr, 3000);
            } catch (IOException e) {
                System.out.println("Connect failed");
                e.printStackTrace();
                return;
            if (sock.isConnected()) {
                   System.out.println("Connected");
            System.out.print("Connect succ");
}output:
Connect failed
java.net.SocketTimeoutException: connect timed out
at java.net.PlainSocketImpl.socketConnect(Native Method)
at java.net.PlainSocketImpl.doConnect(Unknown Source)
at java.net.PlainSocketImpl.connectToAddress(Unknown Source)
at java.net.PlainSocketImpl.connect(Unknown Source)
at java.net.SocksSocketImpl.connect(Unknown Source)
at java.net.Socket.connect(Unknown Source)
at networktest.main(networktest.java:17)
thanks for your help

Decompile applet and proxify all URL and socket connection and recompile

Hi,
Please anybody have idea for the below.
I need to decomple the applet class file to .java file and need to change all URL and Socket connection to proxify all connections from applet. and recompile the sample applet to make ready to load in browser.
Thi is to load the applet form the web server through one proxy server. In the proxy server side While loading the applet from web server that applet code need to be changed to modify the URL and connections used in that applet to change the further connection from applet through proxyserver.
Compile and decompile is not a problem that i can use javac and javap respectively.
But I want to know how to change all URL and connection in applet. is there any easy way to handle this with out changing the applet code.
can Anybody help me.
Thanks and Regards,
Shiban.

Not sure how you do that:
Client <----[HTTPS]-----> Secure Gateway <------[HTTP]------->Web servers
or
Internet Explorer/Mozilla <----[HTTPS]-----> proxy <------[HTTP]-------> Google
Is the above correct?
If so than what are the proxy settings in IE/Moz, I can specify the proxy address in the
browsers but not the proxy type (SSL).
When you want to visit a page like google I gues you just type http://www.google.com in
the browsers address bar. The browser will figure out how to connect to the proxy.
Java has got the control panel in the general tabl there is a button "network settings...:"
I have it to "use browser settings" and this works for me.
All URL and URLConnections work but the sockets don't (maybe put in a bug report)
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In the trace I can see:
network: Connecting http://yog70.games.scd.yahoo.com/yog/y/b/us-t1.ldict with proxy=HTTP @ myproxy/00.00.00.00:80
network: Connecting socket://yog70.games.scd.yahoo.com:11999 with proxy=DIRECT
The second one fails because port 11999 is not open (what idiot uses an unassigned
port for a profesional site is beyond me).
http://www.iana.org/assignments/port-numbers
# 11968-11999 Unassiged
Even if the port was open on the proxy you'll notice with proxy=DIRECT that
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the bin dir of java.home) and make sure it is set to "use browser settings"
Then enable a full trace:
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C:\Program Files\Java\j2re1.4...\bin\jpicpl32.exe
In the advanced tab you can fill in something for runtime parameters fill in this:
-Djavaplugin.trace=true -Djavaplugin.trace.option=basic|net|security|ext|liveconnect
if you cannot start the java console check here:
C:\Documents and Settings\userName\Application Data\Sun\Java\Deployment\deployment.properties
I think for linux this is somewhere in youruserdir/java (hidden directory)
add or change the following line:
javaplugin.jre.params=-Djavaplugin.trace\=true -Djavaplugin.trace.option\=basic|net|security|ext|liveconnect
for 1.5:
deployment.javapi.jre.1.5.0.args=-Djavaplugin.trace\=true -Djavaplugin.trace.option\=basic|net|security|ext|liveconnect
The trace is here:
C:\Documents and Settings\your user\Application Data\Sun\Java\Deployment\log\plugin...log
I think for linux this is somewhere in youruserdir/java (hidden directory)
Print out the full trace of the exception:
try{...}catch(Exception e){e.printStackTrace();}
Then visit the games.yahoo and try to create a new table playing bridge.
Inspect the trace and see if it works/why it doesn't work.

Establish socket connection with local pc using Applet

Hi,
I want to write an applet embedded in my web application.
When I access the web application from my PC which is connected to a RFID reader, I need the applet to make a socket connection to the attached RFID reader.
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If not, what do I need to make this possible for applet?
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Thank you.

HI Helen,
Just to check.
He is on XP ?
He is using AIM 5.9 ?
He has Tuned the camera and Mic to the App ?
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Either using UPnP or these actual ports
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Socket connection in Applet

Hi champ,
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Thanks in advance.
Nischal

Security model for the applets doesn't allow you to connect to hosts other then host where you download applet code. To go through that limit you have to sign your applet code or provide a proxy on your web site hosting a applet.
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Applet using socket connection always go through proxy server

Socket connection with socks always go through proxy server
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Thanks in advance.

Hi,
I am not very much sure if I can help you. In my previous experience, once you set the system property to use the proxy, then the jvm uses the proxy. If you want disable, in your code, you have to disable it.
like System.setProperty("socksProxyHost","someHost"), Properties props = System.getProperties(); props.remove(("socksProxyHost");

Applet socket problem in client-server, urgent!

Dear All:
I have implemented a client server teamwork environment. I have managered to get the server running fine. The server is responsible for passing messages between clients and accessing Oracle database using JDBC. The client is a Java Applet. The code is like the following. The problem is when I try to register the client, the socket connection get java.security.AccessControlException: access denied(java.net.SocketPermission mugca.its.monash.edu.
au resolve)
However, I have written a Java application with the same socket connection method to connect to the same server, it connects to the server without any problem. Is it because of the applet security problem? How should I solve it? Very appreciate for any ideas.
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class Authentication extends Dialog implements ActionListener, KeyListener {
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dispose();
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public ConnectionStreams getConnectionStreams() {
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// authenticates the user
private void authenticateUser() {
Socket socket;
InetAddress address;
try {
// open socket to server
System.out.println("Ready to connect to server on: " + port);
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address.getAddress() + ";\n" +
address.getHostAddress() + ";\n" +
address.getLocalHost());
catch(Exception e) {
displayMessage("Error occured. See console");
System.err.println(e);
e.printStackTrace();
}

Hi, there:
Thanks for the help. But I don't have to configure the security policy. Instead, inspired by a message in this forum, I simply upload the applet to the HTTP server (mugca.its.monash.edu.au) where my won server is running. Then the applet is download from the server and running fine in my local machine.
Dengsheng

Servlet/applet/socket problem

Hi there,
my problem is this...
i create a page with an servlet whicht shows an applet. this applet connects to a server through an socket. it works fine, but, when i change the page and the applet is not longer on the screen, the socket connection will be not killed! i dont know why. but i must kill it when the applet is not longer on the screen...whats wrong? can you help me?
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Help with an exception when trying to establish a socket connection

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at java.net.InetAddress.getAllByName0(InetAddress.java:937)
at java.net.InetAddress.getAllByName0(InetAddress.java:918)
at java.net.InetAddress.getAllByName(InetAddress.java:912)
at java.net.InetAddress.getByName(InetAddress.java:832)
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i thank you for taking the time to help me......i have been reading through the posts in this forum, and am seeing it is a good place to get help, so i will be sticking around.....
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Applet Servlet Connection

Hi,
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?

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to it. Like
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Can a socket connection be created inside a Timeline to port 23?

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Regards,
Richard

Here is the Timeline code:
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var sConn:Socket;
var reader:BufferedReader;
var s:String;
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repeatCount: Timeline.INDEFINITE
keyFrames: [
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s = reader.readLine();
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Thanks.

- By origin host, is it the host from where the html is downloaded or the host from where
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allthough a socket doesn't use the browser's settings to make a connection and you
can have problems when the client uses a proxy or https.
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Here is the list of enhancements in JDK1.5.
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Here is the list
http://java.sun.com/j2se/1.5.0/docs/guide/net/properties.html

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