Develop Reference

Running shell script using JSch with sudo option [duplicate]

Using jsch
when i run the following cmd 'sudo su -' the program hangs
[TestNG] Running:
C:\Users\brian.crosby\AppData\Local\Temp\testng-eclipse-952620154\testng-customsuite.xml
[root#tbx2-toy-1 ~]#
It looks like the "sudo su -" worked becasue the output states "[root#tbx2-toy-1 ~]#" but when i send it another cmd it is unresponsive.
heres the code:
package com.linux;
import java.io.InputStream;
import org.testng.annotations.*;
import com.jcraft.jsch.*;
import com.thoughtworks.selenium.*;
public class LinuxConnection extends SeleneseTestBase{
String host = null;
private StringBuilder strFileData;
String randomFileName = null;
public String getFileData() {
return strFileData.toString();
}
public String getRandomFileName() {
return randomFileName;
}
public LinuxConnection() {
strFileData = new StringBuilder();
}
#Test
public void createUpdateTBX2FileData(String command)throws Exception {
try {
JSch jsch = new JSch();
host = "brian-crosby#************.net";
String user = host.substring(0, host.indexOf('#'));
host = host.substring(host.indexOf('#') + 1);
Session session = jsch.getSession(user, host, 22);
UserInfo ui = new MyUserInfo();
session.setUserInfo(ui);
session.connect();
ChannelExec channel = (ChannelExec)session.openChannel("exec");
((ChannelExec)channel).setPty(true);
((ChannelExec) channel).setCommand(command);
((ChannelExec) channel).setErrStream(System.err);
InputStream in = channel.getInputStream();
channel.connect();
byte[] tmp = new byte[2048];
while (in.read(tmp, 0, 2048) > 0) {
String str = new String(tmp);
strFileData.append(str);
System.out.println(strFileData);
}
in.close();
channel.disconnect();
session.disconnect();
} catch (Exception e) {
System.out.println(e);
}
}
public static class MyUserInfo implements UserInfo {
public String getPassword() {
return "********";
}
public boolean promptYesNo(String str) {
str = "Yes";
return true;
}
String passwd;
public String getPassphrase() {
return null;
}
public boolean promptPassphrase(String message) {
return true;
}
public boolean promptPassword(String message) {
passwd = "*******";
return true;
}
public void showMessage(String message) {
}
}
}
Here is where i am sending the cmds:
package com.linux;
import org.testng.annotations.*;
public class testLinuxConnection {
#Test
public void testLinux() throws Exception{
LinuxConnection obj = new LinuxConnection();
String command = "touch tester1.txt; sudo su -; rm tester1.txt;";
obj.createUpdateTBX2FileData(command);
}
}
Again i have spent hours on google trying to find a solution but was unsuccessful
Any help is appreciated

You are code is missing the rest of the code needed for this to run. You need to initialize the type of channel you need out of the initialized session object. Since you need to be able to run more than one command after each other, you need a Shell type channel:
You should check JSch's examples (i.e. Shell.java), here it is for a quick reference:
/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
/**
* This program enables you to connect to sshd server and get the shell prompt.
* $ CLASSPATH=.:../build javac Shell.java
* $ CLASSPATH=.:../build java Shell
* You will be asked username, hostname and passwd.
* If everything works fine, you will get the shell prompt. Output will
* be ugly because of lacks of terminal-emulation, but you can issue commands.
*
*/
import com.jcraft.jsch.*;
import java.awt.*;
import javax.swing.*;
public class Shell{
public static void main(String[] arg){
try{
JSch jsch=new JSch();
//jsch.setKnownHosts("/home/foo/.ssh/known_hosts");
String host=null;
if(arg.length>0){
host=arg[0];
}
else{
host=JOptionPane.showInputDialog("Enter username#hostname",
System.getProperty("user.name")+
"#localhost");
}
String user=host.substring(0, host.indexOf('#'));
host=host.substring(host.indexOf('#')+1);
Session session=jsch.getSession(user, host, 22);
String passwd = JOptionPane.showInputDialog("Enter password");
session.setPassword(passwd);
UserInfo ui = new MyUserInfo(){
public void showMessage(String message){
JOptionPane.showMessageDialog(null, message);
}
public boolean promptYesNo(String message){
Object[] options={ "yes", "no" };
int foo=JOptionPane.showOptionDialog(null,
message,
"Warning",
JOptionPane.DEFAULT_OPTION,
JOptionPane.WARNING_MESSAGE,
null, options, options[0]);
return foo==0;
}
// If password is not given before the invocation of Session#connect(),
// implement also following methods,
// * UserInfo#getPassword(),
// * UserInfo#promptPassword(String message) and
// * UIKeyboardInteractive#promptKeyboardInteractive()
};
session.setUserInfo(ui);
// It must not be recommended, but if you want to skip host-key check,
// invoke following,
// session.setConfig("StrictHostKeyChecking", "no");
//session.connect();
session.connect(30000); // making a connection with timeout.
Channel channel=session.openChannel("shell");
// Enable agent-forwarding.
//((ChannelShell)channel).setAgentForwarding(true);
channel.setInputStream(System.in);
/*
// a hack for MS-DOS prompt on Windows.
channel.setInputStream(new FilterInputStream(System.in){
public int read(byte[] b, int off, int len)throws IOException{
return in.read(b, off, (len>1024?1024:len));
}
});
*/
channel.setOutputStream(System.out);
/*
// Choose the pty-type "vt102".
((ChannelShell)channel).setPtyType("vt102");
*/
/*
// Set environment variable "LANG" as "ja_JP.eucJP".
((ChannelShell)channel).setEnv("LANG", "ja_JP.eucJP");
*/
//channel.connect();
channel.connect(3*1000);
}
catch(Exception e){
System.out.println(e);
}
}
public static abstract class MyUserInfo
implements UserInfo, UIKeyboardInteractive{
public String getPassword(){ return null; }
public boolean promptYesNo(String str){ return false; }
public String getPassphrase(){ return null; }
public boolean promptPassphrase(String message){ return false; }
public boolean promptPassword(String message){ return false; }
public void showMessage(String message){ }
public String[] promptKeyboardInteractive(String destination,
String name,
String instruction,
String[] prompt,
boolean[] echo){
return null;
}
}
}

jsch and running "sudo su -"

Using jsch
when i run the following cmd 'sudo su -' the program hangs
[TestNG] Running:
C:\Users\brian.crosby\AppData\Local\Temp\testng-eclipse-952620154\testng-customsuite.xml
[root#tbx2-toy-1 ~]#
It looks like the "sudo su -" worked becasue the output states "[root#tbx2-toy-1 ~]#" but when i send it another cmd it is unresponsive.
heres the code:
package com.linux;
import java.io.InputStream;
import org.testng.annotations.*;
import com.jcraft.jsch.*;
import com.thoughtworks.selenium.*;
public class LinuxConnection extends SeleneseTestBase{
String host = null;
private StringBuilder strFileData;
String randomFileName = null;
public String getFileData() {
return strFileData.toString();
}
public String getRandomFileName() {
return randomFileName;
}
public LinuxConnection() {
strFileData = new StringBuilder();
}
#Test
public void createUpdateTBX2FileData(String command)throws Exception {
try {
JSch jsch = new JSch();
host = "brian-crosby#************.net";
String user = host.substring(0, host.indexOf('#'));
host = host.substring(host.indexOf('#') + 1);
Session session = jsch.getSession(user, host, 22);
UserInfo ui = new MyUserInfo();
session.setUserInfo(ui);
session.connect();
ChannelExec channel = (ChannelExec)session.openChannel("exec");
((ChannelExec)channel).setPty(true);
((ChannelExec) channel).setCommand(command);
((ChannelExec) channel).setErrStream(System.err);
InputStream in = channel.getInputStream();
channel.connect();
byte[] tmp = new byte[2048];
while (in.read(tmp, 0, 2048) > 0) {
String str = new String(tmp);
strFileData.append(str);
System.out.println(strFileData);
}
in.close();
channel.disconnect();
session.disconnect();
} catch (Exception e) {
System.out.println(e);
}
}
public static class MyUserInfo implements UserInfo {
public String getPassword() {
return "********";
}
public boolean promptYesNo(String str) {
str = "Yes";
return true;
}
String passwd;
public String getPassphrase() {
return null;
}
public boolean promptPassphrase(String message) {
return true;
}
public boolean promptPassword(String message) {
passwd = "*******";
return true;
}
public void showMessage(String message) {
}
}
}
Here is where i am sending the cmds:
package com.linux;
import org.testng.annotations.*;
public class testLinuxConnection {
#Test
public void testLinux() throws Exception{
LinuxConnection obj = new LinuxConnection();
String command = "touch tester1.txt; sudo su -; rm tester1.txt;";
obj.createUpdateTBX2FileData(command);
}
}
Again i have spent hours on google trying to find a solution but was unsuccessful
Any help is appreciated

You are code is missing the rest of the code needed for this to run. You need to initialize the type of channel you need out of the initialized session object. Since you need to be able to run more than one command after each other, you need a Shell type channel:
You should check JSch's examples (i.e. Shell.java), here it is for a quick reference:
/* -*-mode:java; c-basic-offset:2; indent-tabs-mode:nil -*- */
/**
* This program enables you to connect to sshd server and get the shell prompt.
* $ CLASSPATH=.:../build javac Shell.java
* $ CLASSPATH=.:../build java Shell
* You will be asked username, hostname and passwd.
* If everything works fine, you will get the shell prompt. Output will
* be ugly because of lacks of terminal-emulation, but you can issue commands.
*
*/
import com.jcraft.jsch.*;
import java.awt.*;
import javax.swing.*;
public class Shell{
public static void main(String[] arg){
try{
JSch jsch=new JSch();
//jsch.setKnownHosts("/home/foo/.ssh/known_hosts");
String host=null;
if(arg.length>0){
host=arg[0];
}
else{
host=JOptionPane.showInputDialog("Enter username#hostname",
System.getProperty("user.name")+
"#localhost");
}
String user=host.substring(0, host.indexOf('#'));
host=host.substring(host.indexOf('#')+1);
Session session=jsch.getSession(user, host, 22);
String passwd = JOptionPane.showInputDialog("Enter password");
session.setPassword(passwd);
UserInfo ui = new MyUserInfo(){
public void showMessage(String message){
JOptionPane.showMessageDialog(null, message);
}
public boolean promptYesNo(String message){
Object[] options={ "yes", "no" };
int foo=JOptionPane.showOptionDialog(null,
message,
"Warning",
JOptionPane.DEFAULT_OPTION,
JOptionPane.WARNING_MESSAGE,
null, options, options[0]);
return foo==0;
}
// If password is not given before the invocation of Session#connect(),
// implement also following methods,
// * UserInfo#getPassword(),
// * UserInfo#promptPassword(String message) and
// * UIKeyboardInteractive#promptKeyboardInteractive()
};
session.setUserInfo(ui);
// It must not be recommended, but if you want to skip host-key check,
// invoke following,
// session.setConfig("StrictHostKeyChecking", "no");
//session.connect();
session.connect(30000); // making a connection with timeout.
Channel channel=session.openChannel("shell");
// Enable agent-forwarding.
//((ChannelShell)channel).setAgentForwarding(true);
channel.setInputStream(System.in);
/*
// a hack for MS-DOS prompt on Windows.
channel.setInputStream(new FilterInputStream(System.in){
public int read(byte[] b, int off, int len)throws IOException{
return in.read(b, off, (len>1024?1024:len));
}
});
*/
channel.setOutputStream(System.out);
/*
// Choose the pty-type "vt102".
((ChannelShell)channel).setPtyType("vt102");
*/
/*
// Set environment variable "LANG" as "ja_JP.eucJP".
((ChannelShell)channel).setEnv("LANG", "ja_JP.eucJP");
*/
//channel.connect();
channel.connect(3*1000);
}
catch(Exception e){
System.out.println(e);
}
}
public static abstract class MyUserInfo
implements UserInfo, UIKeyboardInteractive{
public String getPassword(){ return null; }
public boolean promptYesNo(String str){ return false; }
public String getPassphrase(){ return null; }
public boolean promptPassphrase(String message){ return false; }
public boolean promptPassword(String message){ return false; }
public void showMessage(String message){ }
public String[] promptKeyboardInteractive(String destination,
String name,
String instruction,
String[] prompt,
boolean[] echo){
return null;
}
}
}

LDAP bind/search in servlet JAVA

I have builded a Java server that listen on a port (6666). Now, i need to connect to this server with a LDAP Browser (I use Softerra). The connection is done, but i have to know when there is an LDAP bind/search, and i have no idea of how to do that.
Here is the code of my server (feel free to tell me if it's not very clear/good, i'm quite new to Java Prog.):
package net.nantes.littleldap;
import java.net.*;
import java.io.*;
public class Serverside {
public static void main(String[] args) {
ServerSocket socketserver ;
Socket socket ;
BufferedReader in;
PrintWriter out;
try {
Authenticate auth = new Authenticate();
socketserver = new ServerSocket(6666);
System.out.println("Le serveur est à l'écoute du port "+socketserver.getLocalPort());
auth.connect();
socket = socketserver.accept();
String inputLine = new String();
in = new BufferedReader(
new InputStreamReader(
socket.getInputStream()));
System.out.println("Connecté au serveur");
while ((inputLine = in.readLine()) != null){
System.out.println(inputLine);
out = new PrintWriter(socket.getOutputStream());
out.println("Connection réussie");
out.flush();
}
socket.close();
socketserver.close();
}catch (IOException e) {
e.printStackTrace();
}
}
}
Sorry, the message are in french, but it's not really important. I think maybe I could do something with InputLine (when I print it, it returns some String relative to LDAP, but i can be hard to parse).
So, any idea ? Thanks a lot !

I would strongly recommend you utilize either JNDI or one of the LDAP SDKs that are available.
We like: https://www.unboundid.com/products/ldap-sdk/
-jim

In addition to listening to the port, your server has to "understand" the LDAP protocol.
I use the OpenDS LDAP SDK (http://www.middleware.vt.edu/pubs/opends-sdk-0.9.0/).
Code is like this
public class MyLdapServer
implements ServerConnectionFactory<LDAPClientContext, Integer> {
private LDAPListener listener;
public void init() {
try {
listener = new LDAPListener(1389, this);
} catch (IOException e) {
logger.error("error opening LDAP listener", e);
}
}
public void destroy() {
listener.close();
}
#Override
public ServerConnection<Integer> handleAccept(LDAPClientContext context)
throws ErrorResultException {
if (logger.isDebugEnabled())
logger.debug("ldap connection from: " + context.getPeerAddress());
IncomingLdapConnection ilc = new IncomingLdapConnection(context);
return ilc;
}
private static Logger logger = LoggerFactory.getLogger(MyLdapServer.class);
}
The IncomingLdapConnection allows you to handle the LDAP operations:
public class IncomingLdapConnection
implements ServerConnection<Integer> {
public void handleBind(Integer ctx, int version, BindRequest request,
ResultHandler<? super BindResult> resultHandler,
IntermediateResponseHandler intermediateResponseHandler)
throws UnsupportedOperationException {
if (request.getAuthenticationType() != -128) {
logger.warn("LDAP BIND: unsupported authentication type: " + request.getAuthenticationType());
resultHandler.handleResult(Responses.newBindResult(ResultCode.AUTH_METHOD_NOT_SUPPORTED));
return;
}
String bindName = request.getName();
if (bindName.length() > 0) {
if (request instanceof GenericBindRequest) {
GenericBindRequest bindRequest = (GenericBindRequest)request;
String userName = parseUidDn(bindName);
if (userName == null) {
// manche LDAP-Clients senden keine DN, sondern direkt den Namen
userName = bindName;
}
String password = bindRequest.getAuthenticationValue().toString();
logger.debug("LDAP BIND: non-anonymous bind, user = " + userName);
anonymous = false;
} else {
logger.warn("LDAP BIND: non-anonymous bind, but unsupported request");
resultHandler.handleResult(Responses.newBindResult(ResultCode.AUTH_METHOD_NOT_SUPPORTED));
return;
}
} else {
logger.debug("LDAP BIND: anonymous bind");
anonymous = true;
}
boolean success = anonymous;
if (!anonymous) {
// authenticate user, set "success"
}
if (success)
resultHandler.handleResult(Responses.newBindResult(ResultCode.SUCCESS));
else
resultHandler.handleResult(Responses.newBindResult(ResultCode.INVALID_CREDENTIALS));
authenticated = success;
}
EDIT:
OpenDS Code for answering to LDAP search requests
public void handleSearch(Integer ctx, SearchRequest request,
SearchResultHandler responseHandler, IntermediateResponseHandler intermediateResponseHandler)
throws UnsupportedOperationException {
if (request.getScope() == SearchScope.BASE_OBJECT && request.getName().isRootDN()) {
logger.debug("LDAP Search: BASE_OBJECT");
responseHandler.handleEntry(Responses.newSearchResultEntry(rootEntry));
} else {
// do the search
// parameters: request.getName(), request.getScope(), request.getFilter()
}
responseHandler.handleResult(Responses.newResult(ResultCode.SUCCESS));
}

Check out the UnboundID LDAP SDK and some sample code.
EDIT:
I would not recommend the use of JNDI:
JNDI uses a deprecated configuration
JNDI has software defects
JNDI does not fully support LDAP standards
see also
LDAP: Programming Practices

Advice needed for android phonegap custom plugin

I have developed an app in phonegap (html5, JQuery, JS) and I want to develop a plugin to print to a BT printer.
I download printer manufacturer's SDK and I imported the appropriate .jar file to my project with all the methods I will need in my project.
I create the below plugin, following an internet tutorial, in order to call from JS the JAVA methods from printer manufacturers SDK.
JS
var HelloPlugin = {
callNativeFunction: function (success, fail, resultType) {
return cordova.exec(success, fail, "com.tricedesigns.HelloPlugin", "nativeAction", [resultType]);
}
};
JAVA
package com.tricedesigns;
import org.apache.cordova.api.Plugin;
import org.apache.cordova.api.PluginResult;
import org.json.JSONArray;
import com.starmicronics.stario.StarIOPort;
import com.starmicronics.stario.StarIOPortException;
import com.starmicronics.stario.StarPrinterStatus;
import android.app.AlertDialog;
import android.app.AlertDialog.Builder;
import android.content.Context;
import android.util.Log;
public class HelloPlugin extends Plugin {
public static final String NATIVE_ACTION_STRING="nativeAction";
public static final String SUCCESS_PARAMETER="success";
#Override
public PluginResult execute(String action, JSONArray data, String callbackId) {
if (NATIVE_ACTION_STRING.equals(action)) {
this.ctx.runOnUiThread(new Runnable()
{
public void run()
{
String resultType = null;
StarIOPort port = null;
String message = null;
String portName = "bt:";
String portSettings = "mini";
byte[] texttoprint = new byte[]{0x1b, 0x40, 0x1b,0x74,0x0D,(byte) 0x91,(byte) 0x92,(byte) 0x93,(byte) 0x94,(byte) 0x95,(byte) 0x96,(byte) 0x97,(byte) 0x98,(byte) 0x99,0x0A,0x0A,0x0A,0x0A,0x0A};
try
{
port = StarIOPort.getPort(portName, portSettings, 10000);
try
{
Thread.sleep(500);
}
catch(InterruptedException e) {}
}
catch (StarIOPortException e)
{
Builder dialog = new AlertDialog.Builder((Context)ctx);
dialog.setNegativeButton("Ok", null);
AlertDialog alert = dialog.create();
alert.setTitle("Failure");
alert.setMessage("Failed to connect to printer");
alert.show();
}
finally
{
if(port != null)
{
try
{
StarIOPort.releasePort(port);
} catch (StarIOPortException e) {}
}
}
}
});
}
return null;
}
}
Printer command manual say:
GetPort is what you will be using to “open” the port to the printer. Using one of the valid
inputs for portName and portSettings as mentioned previously before this, you can pass your
connection string into the StarIO class so that it will correctly set its private variables.
//The following would be an actual usage of getPort:
StarIOPort port = null;
try
{
port = StarIOPort.getPort(portName, portSettings, 10000);
}
catch (StarIOPortException e)
{
//There was an error opening the port
}
StarIOPort is a part of StarIO and this will allow you to create a “port” handle. The
above example shows the port being created and set to null then being assigned the actual
port hook on the following line that contains getPort.
Always use a try, catch when using getPort. If the port cannot be opened
because of connection problems, your program will crash unless you use a
try, catch like the above example.
Is the above syntax of plugin correct or is there something i missed?
When I run my app always i receive "Failed to connect to printer" even if the printer is on and connected to my device.

try this:
public PluginResult execute(String action, JSONArray data, String callbackId) {
PluginResult result = null;
if (PRINT_ACTION.equals(action))
{
JSONObject printerStatusJSON = new JSONObject();
try {
Boolean prtStatus = false;
String msg ="Failed to connect to printer";
String portName = "";
ArrayList<PortInfo> dvss = PrinterFunctions.getDevices();//BTPortList = StarIOPort.searchPrinter("BT:");
if (Looper.myLooper() == null) {
Looper.prepare();
}
for(PortInfo dvs : dvss) {
Map<String, String> st = PrinterFunctions.CheckStatus(dvs.getPortName(), "mini");//port = StarIOPort.getPort(portName, portSettings, 1000);
if(st.get("status") == "true") {
prtStatus = true;
portName = st.get("portName");
break;
}
msg = st.get("message");
}
if(!portName.isEmpty()) {
PrinterFunctions.PrintSomething(portName, data);//MiniPrinterFunctions.PrintSampleReceipt(String portName, JSONArray data);
}
printerStatusJSON.put("prtStatus", prtStatus);
printerStatusJSON.put("message", msg);
result = new PluginResult(Status.OK, printerStatusJSON);
}
catch (Exception jsonEx) {
Log.e("YourApplicationName", "Got JSON Exception " + jsonEx.getMessage());
jsonEx.printStackTrace();
result = new PluginResult(Status.JSON_EXCEPTION);
}
}
else {
result = new PluginResult(Status.INVALID_ACTION);
Log.e(TAG, "Invalid action : " + action);
}
return result;
}

Running a Client-Server Chat program

This is one of the most common application scenario that can be found all over the net. and I'm not asking any questions about the java codes that I did because I was successful in running it on my laptop where both the client and server part of the .java file resides. Rather I have had problem getting it to work in between two computers. I tried establishing physical connection using cross-over cable to connect two computers, and did a test to see if file transfers successfully and it did, however, keeping one Server part of the .java file in one computer and client part in the other, I tried to run the server first and then the client but it got a "access denied" error.
For reference here's my two .java files:
/* ChatClient.java */
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.IOException;
import java.io.PrintWriter;
import java.net.Socket;
import java.net.UnknownHostException;
public class ChatClient {
private static int port = 5000; /* port to connect to */
private static String host = "localhost"; /* host to connect to (server's IP)*/
private static BufferedReader stdIn;
private static String nick;
/**
* Read in a nickname from stdin and attempt to authenticate with the
* server by sending a NICK command to #out. If the response from #in
* is not equal to "OK" go bacl and read a nickname again
*/
private static String getNick(BufferedReader in,
PrintWriter out) throws IOException {
System.out.print("Enter your nick: ");
String msg = stdIn.readLine();
out.println("NICK " + msg);
String serverResponse = in.readLine();
if ("SERVER: OK".equals(serverResponse)) return msg;
System.out.println(serverResponse);
return getNick(in, out);
}
public static void main (String[] args) throws IOException {
Socket server = null;
try {
server = new Socket(host, port);
} catch (UnknownHostException e) {
System.err.println(e);
System.exit(1);
}
stdIn = new BufferedReader(new InputStreamReader(System.in));
/* obtain an output stream to the server... */
PrintWriter out = new PrintWriter(server.getOutputStream(), true);
/* ... and an input stream */
BufferedReader in = new BufferedReader(new InputStreamReader(
server.getInputStream()));
nick = getNick(in, out);
/* create a thread to asyncronously read messages from the server */
ServerConn sc = new ServerConn(server);
Thread t = new Thread(sc);
t.start();
String msg;
/* loop reading messages from stdin and sending them to the server */
while ((msg = stdIn.readLine()) != null) {
out.println(msg);
}
}
}
class ServerConn implements Runnable {
private BufferedReader in = null;
public ServerConn(Socket server) throws IOException {
/* obtain an input stream from the server */
in = new BufferedReader(new InputStreamReader(
server.getInputStream()));
}
public void run() {
String msg;
try {
/* loop reading messages from the server and show them
* on stdout */
while ((msg = in.readLine()) != null) {
System.out.println(msg);
}
} catch (IOException e) {
System.err.println(e);
}
}
}
and here's the ChatServer.java:
/* ChatServer.java */
import java.net.ServerSocket;
import java.net.Socket;
import java.io.IOException;
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.util.Hashtable;
public class ChatServer {
private static int port = 5000; /* port to listen on */
public static void main (String[] args) throws IOException
{
ServerSocket server = null;
try {
server = new ServerSocket(port); /* start listening on the port */
} catch (IOException e) {
System.err.println("Could not listen on port: " + port);
System.err.println(e);
System.exit(1);
}
Socket client = null;
while(true) {
try {
client = server.accept();
} catch (IOException e) {
System.err.println("Accept failed.");
System.err.println(e);
System.exit(1);
}
/* start a new thread to handle this client */
Thread t = new Thread(new ClientConn(client));
t.start();
}
}
}
class ChatServerProtocol {
private String nick;
private ClientConn conn;
/* a hash table from user nicks to the corresponding connections */
private static Hashtable<String, ClientConn> nicks =
new Hashtable<String, ClientConn>();
private static final String msg_OK = "OK";
private static final String msg_NICK_IN_USE = "NICK IN USE";
private static final String msg_SPECIFY_NICK = "SPECIFY NICK";
private static final String msg_INVALID = "INVALID COMMAND";
private static final String msg_SEND_FAILED = "FAILED TO SEND";
/**
* Adds a nick to the hash table
* returns false if the nick is already in the table, true otherwise
*/
private static boolean add_nick(String nick, ClientConn c) {
if (nicks.containsKey(nick)) {
return false;
} else {
nicks.put(nick, c);
return true;
}
}
public ChatServerProtocol(ClientConn c) {
nick = null;
conn = c;
}
private void log(String msg) {
System.err.println(msg);
}
public boolean isAuthenticated() {
return ! (nick == null);
}
/**
* Implements the authentication protocol.
* This consists of checking that the message starts with the NICK command
* and that the nick following it is not already in use.
* returns:
* msg_OK if authenticated
* msg_NICK_IN_USE if the specified nick is already in use
* msg_SPECIFY_NICK if the message does not start with the NICK command
*/
private String authenticate(String msg) {
if(msg.startsWith("NICK")) {
String tryNick = msg.substring(5);
if(add_nick(tryNick, this.conn)) {
log("Nick " + tryNick + " joined.");
this.nick = tryNick;
return msg_OK;
} else {
return msg_NICK_IN_USE;
}
} else {
return msg_SPECIFY_NICK;
}
}
/**
* Send a message to another user.
* #recepient contains the recepient's nick
* #msg contains the message to send
* return true if the nick is registered in the hash, false otherwise
*/
private boolean sendMsg(String recipient, String msg) {
if (nicks.containsKey(recipient)) {
ClientConn c = nicks.get(recipient);
c.sendMsg(nick + ": " + msg);
return true;
} else {
return false;
}
}
/**
* Process a message coming from the client
*/
public String process(String msg) {
if (!isAuthenticated())
return authenticate(msg);
String[] msg_parts = msg.split(" ", 3);
String msg_type = msg_parts[0];
if(msg_type.equals("MSG")) {
if(msg_parts.length < 3) return msg_INVALID;
if(sendMsg(msg_parts[1], msg_parts[2])) return msg_OK;
else return msg_SEND_FAILED;
} else {
return msg_INVALID;
}
}
}
class ClientConn implements Runnable {
private Socket client;
private BufferedReader in = null;
private PrintWriter out = null;
ClientConn(Socket client) {
this.client = client;
try {
/* obtain an input stream to this client ... */
in = new BufferedReader(new InputStreamReader(
client.getInputStream()));
/* ... and an output stream to the same client */
out = new PrintWriter(client.getOutputStream(), true);
} catch (IOException e) {
System.err.println(e);
return;
}
}
public void run() {
String msg, response;
ChatServerProtocol protocol = new ChatServerProtocol(this);
try {
/* loop reading lines from the client which are processed
* according to our protocol and the resulting response is
* sent back to the client */
while ((msg = in.readLine()) != null) {
response = protocol.process(msg);
out.println("SERVER: " + response);
}
} catch (IOException e) {
System.err.println(e);
}
}
public void sendMsg(String msg) {
out.println(msg);
}
}
Now, what should I do in order to run this two files from two computers given that I have the physical connection(TCP/IP) setup already??
Thanks in advance... :)

Sounds like it's quite possibly a firewall problem. Have you tried opening a hole in your firewall for port 1001?

Have you also looked at your java.policy and make sure that it is configured to allow local codebase to open sockets?

as mentioned in comment, you should not use port < 1025 for you applications, since they are always used in deamon processes. However you should test your program like this
1) if you get connection refused then you should check the exception properly, whether client program takes time before generating exception ( that mean request is going to server and then it's giving connection refused), in that case you should try java.policy put following in a file named java.policy
grant {
permission java.net.SocketPermission ":1024-65535",
"connect,accept";
permission java.net.SocketPermission ":80", "connect";
permission java.io.FilePermission "", "read,write,delete";
permission java.security.SecurityPermission "";
};
while compiling use this flag -Djava.security.policy=java.policy
more-over you should also try -Djava.rmi.server.hostname=IP, where IP is clien-ip for client.java and server-ip for server.java
2) if you are immediately getting exception at client side then your request is not going outside your pc, so client has some problem.
check the exception properly and post them over here.
3) though i've not got access denied error, but it seems to have port problem that might be solved using policy or port>1024.
post what are you getting now.