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How to access a string called "numberPart" from a different file (multithreaded java socket programming)

There is a string called numberPart inside a thread class called ServerRecieve. The location where .start() is being called is inside of a different class called Server.
The 'numberPart' will eventually be used as a port for file transferring later on.
My question is: How do I access the numberPart variable inside of the class called Server?
Screenshot of code running (server on left window, client on the right):
server on left window, client on the right
In the left window of the screenshot (server) you can see the that the first port number of the right window's command line argument which is 4021 being sent via a text message, and the server successfully receives it with the message "File transfer port found: 4021". Unfortunately this variable is located inside a different class. I would like to know how to access that variable inside the class called Server.
ServerRecieve code:
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.net.Socket;
public class ServerRecieve extends Thread
{
Socket servSocket;
boolean m_bRunThread = true;
boolean ServerOn = true;
public ServerRecieve(Socket s)
{
super();
servSocket = s;
}
public void run()
{
while(true)
{
try
{
BufferedReader readFromClient = new BufferedReader(new InputStreamReader(servSocket.getInputStream()));
String fromClient = readFromClient.readLine();
String a = fromClient;
int i;
for(i = 0; i < a.length(); i++)
{
char c = a.charAt(i);
if( '0' <= c && c <= '9' )
{
break;
}
}
String alphaPart = a.substring(0, i);
String numberPart = a.substring(i);
System.out.println("Recieved from client: " + alphaPart +"\n");
System.out.println("File transfer port found: " + numberPart + "\n");
//String[] filePortNumber = null;
//filePortNumber[0] = numberPart;
// Server thing = new Server(filePortNumber);
if(fromClient.equals(null))
{
System.exit(0);
}
OutputOptions();
}
catch (IOException e)
{
e.printStackTrace();
}
finally
{
}
}
}
void OutputOptions()
{
System.out.println("Enter an option ('m', 'f', 'x'): ");
System.out.println("(M)essage (send)");
System.out.println("(F)ile (request) ");
System.out.println("e(X)it ");
}
}
Server source:
import java.io.*;
import java.net.*;
import java.util.*;
import javax.imageio.IIOException;
public class Server
{
private String[] serverArgs;
public Socket socket;
public Socket fileSocket;
public boolean keepRunning = true;
public int ConnectOnce = 0;
public String option = "";
public boolean isConnected = false;
public String FILE_TO_SEND = "/Users/nanettegormley/Documents/workspace/assignment2/src/servers/cdm.jpg";
public Server(String[] args) throws IOException
{
// set the instance variable
this.serverArgs = args;
if(ConnectOnce == 0)
{
int port_number1 = Integer.valueOf(serverArgs[1]);
ServerSocket serverSocket = new ServerSocket(port_number1);
socket = serverSocket.accept();
ConnectOnce = 4;
isConnected = true;
}
}
public String[] serverRun2(String[] args) throws IOException
{
serverArgs = args;
serverArgs = Arrays.copyOf(args, args.length);
serverSend.start();
return serverArgs;
}
Thread serverSend = new Thread()
{
public void run()
{
OutputOptions();
while(isConnected)
{
try
{
ServerRecieve serverThread = new ServerRecieve(socket);
serverThread.start();
// input the message from standard input
BufferedReader input2= new BufferedReader(new InputStreamReader(System.in));
option = input2.readLine();
if(option.equals("m") || option.equals("M"))
{
StandardOutput();
}
if(option.equals("f") || option.equals("F"))
{
FileTransferSend();
}
if(option.equals("x") || option.equals("X"))
{
System.exit(0);
}
}
catch ( Exception e )
{
System.out.println( e.getMessage() );
}
}
}
};
public void StandardOutput()
{
try
{
//Send the message to the server
OutputStream os = socket.getOutputStream();
OutputStreamWriter osw = new OutputStreamWriter(os);
BufferedWriter bw = new BufferedWriter(osw);
//creating message to send from standard input
String newmessage = "";
try
{
System.out.println("Enter your message: ");
// input the message from standard input
BufferedReader input2= new BufferedReader(new InputStreamReader(System.in));
String line = "";
line= input2.readLine();
newmessage += line + " ";
}
catch ( Exception e )
{
System.out.println( e.getMessage() );
}
String sendMessage = newmessage;
bw.write(sendMessage + "\n");
bw.newLine();
bw.flush();
System.out.println("Message sent to client: "+sendMessage);
StandardInput();
//run();
}
catch (IOException e)
{
e.printStackTrace();
}
finally
{
}
}
void FileTransferSend()
{
//connect to the filetransfer
try
{
System.out.println("Which file do you want? ");
Scanner scanner = new Scanner(System.in);
String filename = scanner.nextLine();
FileInputStream fis = new FileInputStream(new File(filename));
DataOutputStream dos = new DataOutputStream(new BufferedOutputStream(fileSocket.getOutputStream()));
int element;
while((element = fis.read()) !=1)
{
dos.write(element);
}
byte[] byteBuffer = new byte[1024]; // buffer
while(fis.read(byteBuffer)!= -1)
{
dos.write(byteBuffer);
}
OutputOptions();
// dos.close();
// fis.close();
}
catch (IOException e)
{
e.printStackTrace();
}
finally
{
}
}
void OutputOptions()
{
System.out.println("Enter an option ('m', 'f', 'x'): ");
System.out.println("(M)essage (send)");
System.out.println("(F)ile (request) ");
System.out.println("e(X)it ");
}
public void StandardInput()
{
OutputOptions();
while(true)
{
try
{
// input the message from standard input
BufferedReader input2= new BufferedReader(new InputStreamReader(System.in));
String line2 = "";
option= input2.readLine();
if(option.equals("m") || option.equals("M"))
{
StandardOutput();
}
if(option.equals("f") || option.equals("F"))
{
FileTransferSend();
}
if(option.equals("x") || option.equals("X"))
{
System.exit(0);
}
}
catch ( Exception e )
{
System.out.println( e.getMessage() );
}
finally
{
}
}
}
}
Full code with all files:
https://www.dropbox.com/s/0yq47gapsd3dgjp/folder33.zip?dl=0
My question is: What changes can I make to the code that would allow me to access numberPart while being inside Server?
EDIT: Is there a way to bump a question that hasn't gotten any answers or should I just delete this one and repost it somewhere?

I would think that you could use either a listener or callback pattern to solve this.
(I'm losing my Java memory now that I'm doing C# so please bear with me..)
interface PortAssignable {
public assignPort(int port);
}
Then have the Server class implement that interface
public Server implements PortAssignable {
...
}
And ServerReceive
// Constructor
public ServerRecieve(Socket s, PortAssignable portNotifyListener) {
_portNotifyListener = portNotifyListener;
... your other code ...
}
Make sure when you create an instance of ServerReceive, you pass in your Server instance, via this.
ServerRecieve serverThread = new ServerRecieve(socket, this);
Now, when you get your numberPart, your next line can be
_portNotifyListener.assignPort(numberPart);
How you choose to implement the assignPort method in your Server class is up to you.
P.S. I saw this question from /r/programming.

Multithreading with client server program

I am trying to implement multi threading with a client/server program I have been working on. I need to allow multiple clients to connect to the server at the same time. I currently have 4 classes: a Client, a Server, a Protocol and a Worker to handle the threads. The following code is what I have for those classes:
SocketServer Class:
public class SocketServer {
public static void main(String[] args) throws IOException {
int portNumber = 9987;
try (
ServerSocket serverSocket = new ServerSocket(portNumber);
Socket clientSocket = serverSocket.accept();
PrintWriter out =
new PrintWriter(clientSocket.getOutputStream(), true);
BufferedReader in = new BufferedReader(
new InputStreamReader(clientSocket.getInputStream()));
) {
Thread thread = new Thread(new ClientWorker(clientSocket));
thread.start(); //start thread
String inputLine, outputLine;
// Initiate conversation with client
Protocol prot = new Protocol();
outputLine = prot.processInput(null);
out.println(outputLine);
while ((inputLine = in.readLine()) != null) {
outputLine = prot.processInput(inputLine);
out.println(outputLine);
if (outputLine.equals("quit"))
break;
}
} catch (IOException e) {
System.out.println("Exception caught when trying to listen on port "
+ portNumber + " or listening for a connection");
System.out.println(e.getMessage());
}
}
}
SocketClient Class:
public class SocketClient {
public static void main(String[] args) throws IOException
{
String hostName = "localhost";
int portNumber = 9987;
try (
Socket socket = new Socket(hostName, portNumber);
PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
BufferedReader in = new BufferedReader(
new InputStreamReader(socket.getInputStream()));
) {
BufferedReader stdIn =
new BufferedReader(new InputStreamReader(System.in));
String fromServer;
String fromUser;
while ((fromServer = in.readLine()) != null) {
System.out.println("Server: " + fromServer);
if (fromServer.equals("quit"))
break;
fromUser = stdIn.readLine();
if (fromUser != null) {
System.out.println("Client: " + fromUser);
out.println(fromUser);
}
}
} catch (UnknownHostException e) {
System.err.println("Don't know about host " + hostName);
System.exit(1);
} catch (IOException e) {
System.err.println("Couldn't get I/O for the connection to " +
hostName);
System.exit(1);
}
}
}
Protocol Class:
public class Protocol {
private static final int waiting = 0;
private static final int sentPrompt = 1;
private int status = waiting;
public String processInput(String theInput) {
String theOutput = null;
if (status == waiting) {
theOutput = "Please enter what you would like to retrieve: 'customer' or 'product' ";
status = sentPrompt;
}
else if ( status == sentPrompt ) {
if ( theInput.equalsIgnoreCase("product")) {
File f = new File("product.txt");
Scanner sc = null;
try {
sc = new Scanner(f);
} catch (FileNotFoundException ex) {
Logger.getLogger(Protocol.class.getName()).log(Level.SEVERE, null, ex);
}
while ( sc.hasNextLine() ) {
String line = sc.nextLine();
theOutput = "The current product entries are : " + line;
}
return theOutput;
}
else if ( theInput.equalsIgnoreCase("customer")) {
File f = new File("customer.txt");
Scanner sc = null;
try {
sc = new Scanner(f);
} catch (FileNotFoundException ex) {
Logger.getLogger(Protocol.class.getName()).log(Level.SEVERE, null, ex);
}
while ( sc.hasNextLine() ) {
String line = sc.nextLine();
theOutput = "The current customer entries are : " + line;
}
return theOutput;
}
else if ( theInput.equalsIgnoreCase("quit")) {
return "quit";
}
else {
return "quit";
}
}
return theOutput;
}
}
The ClientWorker Class:
public class ClientWorker implements Runnable {
private final Socket client;
public ClientWorker( Socket client ) {
this.client = client;
}
#Override
public void run() {
String line;
BufferedReader in = null;
PrintWriter out = null;
try {
System.out.println("Thread started with name:"+Thread.currentThread().getName());
in = new BufferedReader(new InputStreamReader(client.getInputStream()));
out = new PrintWriter(client.getOutputStream(), true);
} catch (IOException e) {
System.out.println("in or out failed");
System.exit(-1);
}
while (true) {
try {
System.out.println("Thread running with name:"+Thread.currentThread().getName());
line = in.readLine();
//Send data back to client
out.println(line);
//Append data to text area
} catch (IOException e) {
System.out.println("Read failed");
System.exit(-1);
}
}
}
}
When I run the server and client, everything works fine as expected. Then when I try to run another client, it just hangs there and does not prompt the client to give a response. Any insight into what I am missing is greatly appreciated!

Your server code should address implement below functionalities.
Keep accepting socket from ServerSocket in a while loop
Create new thread after accept() call by passing client socket i.e Socket
Do IO processing in client socket thread e.g ClientWorker in your case.
Have a look at this article
Your code should be
ServerSocket serverSocket = new ServerSocket(portNumber);
while(true){
try{
Socket clientSocket = serverSocket.accept();
Thread thread = new ClientWorker(clientSocket);
thread.start(); //start thread
}catch(Exception err){
err.printStackTrace();
}
}

How many times does serverSocket.accept() get called?
Once.
That's how many clients it will handle.
Subsequent clients trying to contact will not have anybody listening to receive them.
To handle more clients, you need to call serverSocket.accept() in a loop.

Java SocketException: Software caused connection abort

I'm trying to develop a client-server exchange program, and when I try to send data from client to server, I'm running into a SocketException. I've looked at other answers but none of them fit my exact case; I have two calls to osw.write, and only one of them works.
Client:
package me.primesearch.client;
import java.math.BigInteger;
import java.net.*;
import java.io.*;
public class PrimeSearchClient {
public static void main(String[] args) throws IOException{
Socket connection = null;
try{
/** Define a host server */
String host = "localhost";
/** Define a port */
int port = 25564;
StringBuffer instr = new StringBuffer();
System.out.println("SocketClient initialized");
/** Obtain an address object of the server */
InetAddress address = InetAddress.getByName(host);
/** Establish a socket connetion */
connection = new Socket(address, port);
/** Instantiate a BufferedOutputStream object */
BufferedOutputStream bos = new BufferedOutputStream(connection.
getOutputStream());
/** Instantiate a BufferedInputStream object for reading
/** Instantiate a BufferedInputStream object for reading
* incoming socket streams.
*/
BufferedInputStream bis = new BufferedInputStream(connection.
getInputStream());
/**Instantiate an InputStreamReader with the optional
* character encoding.
*/
InputStreamReader isr = new InputStreamReader(bis, "US-ASCII");
/**Read the socket's InputStream and append to a StringBuffer */
int c;
/** Instantiate an OutputStreamWriter object with the optional character
* encoding.
*/
OutputStreamWriter osw = new OutputStreamWriter(bos, "US-ASCII");
while(true){
String process = "drq " + (char) 13;
/** Write across the socket connection and flush the buffer */
osw.write(process);
osw.flush();
while ( (c = isr.read()) != 13)
instr.append( (char) c);
for(int i=0;i<50;i++){
BigInteger offset=new BigInteger(instr.toString()).add(BigInteger.valueOf(i));
if(isProbablyPrime(offset)){
process = "pri" + " " + offset + " " + (offset.divide(new BigInteger("50"))).toString() + (char) 13;
System.out.println(process);
/** Write across the socket connection and flush the buffer */
osw.write(process); //This doesn't work
osw.flush();
System.out.println("Prime found at " + offset);
}
}
}
} catch(IOException e) {
e.printStackTrace();
} finally {
connection.close();
}
}
public static boolean isProbablyPrime(BigInteger n) {
if(n.longValue()!=0){
BigInteger lessOne = n.subtract(BigInteger.ONE);
// get the next prime from one less than number and check with the number
return lessOne.nextProbablePrime().compareTo(n) == 0;
}
return false;
}
}
Server:
package me.primesearch.server;
import java.net.*;
import java.io.*;
public class PrimeSearchServer implements Runnable {
private Socket connection;
#SuppressWarnings("unused")
private int ID;
PrimeSearchServer(Socket s, int i) {
this.connection = s;
this.ID = i;
}
#SuppressWarnings("resource")
public static void main(String[] args) {
int port = 25564;
int count = 0;
try{
ServerSocket socket1 = new ServerSocket(port);
System.out.println("MultipleSocketServer Initialized");
while (true) {
Socket connection = socket1.accept();
Runnable runnable = new PrimeSearchServer(connection, ++count);
Thread thread = new Thread(runnable);
thread.start();
}
}
catch (Exception e) {
e.printStackTrace();
}
}
#Override
public void run() {
try {
BufferedInputStream is = new BufferedInputStream(connection.getInputStream());
InputStreamReader isr = new InputStreamReader(is);
int character;
StringBuffer process = new StringBuffer();
while((character = isr.read()) != 13) {
process.append((char)character);
}
System.out.println(process);
String returnCode="0";
if(process.toString().split(" ")[0].equals("drq")){
System.out.println("Job request recieved");
File file = new File("packages.txt");
//Process input
try (BufferedReader br = new BufferedReader(new FileReader(file))) {
String line;
String prevLine="";
boolean i = false;
int count=0;
while ((line = br.readLine()) != null) {
System.out.println("Looking for a package to send");
// process the line.
if(line.equals("0")){
System.out.println("Sending package " + count);
returnCode = Integer.toString(count);
i = true;
break;
}
prevLine = line;
count++;
System.out.println("No packages found");
}
if(!i){
returnCode = prevLine;
try(PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("packages.txt", true)))) {
System.out.println("Creating new package");
out.println("0");
returnCode=Integer.toString(count);
}catch (IOException e) {
e.printStackTrace();
}
}
}
} else if (process.toString().split(" ")[0].equals("pri")){
System.out.println("Prime request recieved");
try(PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter("primes.txt", true)))) {
out.println(Integer.parseInt(process.toString().split(" ")[1]));
}catch (IOException e) {
e.printStackTrace();
}
updateLine(Integer.parseInt(process.toString().split(" ")[2]));
}
BufferedOutputStream os = new BufferedOutputStream(connection.getOutputStream());
OutputStreamWriter osw = new OutputStreamWriter(os, "US-ASCII");
osw.write(returnCode + (char)13);
osw.flush();
process = new StringBuffer();
}
catch (Exception e) {
System.out.println(e);
}
finally {
try {
connection.close();
}
catch (IOException e){
e.printStackTrace();
}
}
}
private void updateLine(int lines) throws IOException {
String data="packages.txt";
BufferedReader file = new BufferedReader(new FileReader(data));
String input = "";
String line;
for(int i=0;i<lines;i++){
input+=file.readLine()+System.lineSeparator();
}
file.readLine();
while ((line = file.readLine()) != null)
input += line + System.lineSeparator();
FileOutputStream os = new FileOutputStream(data);
os.write(input.getBytes());
file.close();
os.close();
}
}
Sorry if the indenting on the code looks a bit strange, I'm not used to using stack overflow.

You are closing the socket in your server class:
finally {
try {
connection.close();
}
catch (IOException e){
e.printStackTrace();
}
}

I think this is the problem. This is the first message you're sending to the server.
Client
String process = "drq " + (char) 13;
osw.write(process);
osw.flush();
And since your server stops reading after it gets a 13 char it closes the connection after it reads the first message.
Server
while((character = isr.read()) != 13) {
process.append((char)character);
}

I was getting the same exception when running functional test using TestNG. For me it was a version issue. Uninstalling it and installing older version fixed my issue. Read the following post for information.
https://github.com/cbeust/testng-eclipse/issues/91

print BufferedReader while Socket remains open

What I want are just the responses from wunderground printed to the console:
public class Weather {
public static void main(String[] args) {
String host = "rainmaker.wunderground.com";
int port = 3000;
int c;
{
try (Socket socket = new Socket(host, port);
PrintWriter printWriter = new PrintWriter(socket.getOutputStream(), true);
final BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(System.in))) {
while (true) {
System.out.println(socket.toString());
c = bufferedReader.read();
System.out.print((char) c);
}
} catch (IOException ex) {
System.out.println(ex + host + port);
System.exit(1);
} finally {
System.exit(1);
}
}
}
}
However, there's not much output to go on:
thufir#dur:~/NetBeansProjects/MudSocketClient$
thufir#dur:~/NetBeansProjects/MudSocketClient$ java -jar dist/MudSocketClient.jar
Socket[addr=rainmaker.wunderground.com/38.102.137.140,port=3000,localport=53550]
^Cthufir#dur:~/NetBeansProjects/MudSocketClient$
thufir#dur:~/NetBeansProjects/MudSocketClient$
Running telnet from the CLI, the connection works fine.

I found some old code:
public class InputOutput extends Observable {
private static final Logger log = Logger.getLogger(InputOutput.class.getName());
private Alias alias = new Alias();
public InputOutput() {
}
private void readFromConsole(final OutputStream outputStream) {
Thread read = new Thread() {
#Override
public void run() {
String line;
byte[] bytes;
Scanner scanner;
while (true) {
GameDataBean gameData = null;
scanner = new Scanner(System.in);
line = scanner.nextLine();
try {
gameData = alias.parseUserInput(line);
} catch (StringIndexOutOfBoundsException e) {
log.fine(e.toString());
}
if (gameData != null) {
setChanged();
notifyObservers(gameData);
} else {
bytes = line.getBytes();
try {
outputStream.write(bytes);
outputStream.write(10);
outputStream.flush();
} catch (IOException ex) {
log.fine(ex.toString());
}
}
}
}
};
read.start();
}
private void readInput(final InputStream inputStream) throws FileNotFoundException, IOException {
Thread readInput = new Thread() {
#Override
public void run() {
char ch = 0;
int intVal = 0;
StringBuilder sb = new StringBuilder();
try {
while ((intVal = inputStream.read()) != -1) {
ch = (char) intVal;
printToConsole(ch);
//logToFile(ch);
sb.append(ch);
if (intVal == 13) {
setChanged();
notifyObservers(sb.toString());
sb = new StringBuilder();
}
}
} catch (IOException ex) {
Logger.getLogger(InputOutput.class.getName()).log(Level.SEVERE, null, ex);
}
}
private void logToFile(char c) throws IOException {
String fname = "weather.log";
File f = new File(fname);
f.createNewFile();
try (PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter(fname, true)))) {
out.print(c);
out.flush();
}
}
private void printToConsole(char c) {
System.out.print(c);
}
};
readInput.start();
}
public void readWriteParse(final InputStream inputStream, final OutputStream outputStream) throws FileNotFoundException, IOException {
readFromConsole(outputStream);
readInput(inputStream);
}
}
I think it's that, when the socket is still open, it has to be multi-threaded, as I recall.

Overriding the run() method to accept a parameter from the command line

I'm trying to search a word (from a file) specified in the command line using client/server. Here is my code, however it displays nothing when the client part is run. To run the server, type -s <port number> <file.txt> and for the client, -c localhost <port number> <word to be searched> in the command line.
import java.net.*;
import java.util.*;
import java.io.*;
public class quotes {
public static InetAddress host;
public static ServerSocket serverSocket;
public static String target;
public static void main(String[] args) throws IOException {
if(args[0].equals("-c")){
Client(args);
target = args[3];
}
else if(args[0].equals("-s")){
System.out.println("Server");
Server(args);
}
}
#SuppressWarnings("resource")
public static void Client(String[] args) throws IOException{
String hostname = args[1];
if(hostname.equals("localhost")) host = InetAddress.getLocalHost();
else host = InetAddress.getByName(hostname);
int port = Integer.parseInt(args[2]);
Socket socket = new Socket(host, port);
Scanner input = new Scanner(System.in);
Scanner networkInput = new Scanner(socket.getInputStream());
PrintWriter networkOutput = new PrintWriter(socket.getOutputStream(), true);
Scanner userEntry = new Scanner(System.in);
String response;
networkOutput.println(target);
response = networkInput.nextLine();
while(!response.equals("|")){
System.out.println("\n " + response);
response = networkInput.nextLine();
}
}
public static void Server(String[] args) throws IOException {
int port = Integer.parseInt(args[1]);
String file = args[2];
serverSocket = new ServerSocket(port);
do {
Socket client = serverSocket.accept();
System.out.println("\nNew client accepted.\n");
ClientHandler3 handler = new ClientHandler3(client, file);
handler.start();
}while(true);
}
}
class ClientHandler3 extends Thread {
private Socket client;
private Scanner input;
private PrintWriter output;
private ArrayList<String> quotes;
public ClientHandler3(Socket socket, String file) {
client = socket;
try {
BufferedReader buffer = new BufferedReader(new FileReader(file));
BufferedReader reader = new BufferedReader(new InputStreamReader(client.getInputStream()));
String line = reader.readLine();
try {
int ctr = 0;
quotes = new ArrayList<String>();
while(line != null){
quotes.add(ctr, line);
ctr++;
line = buffer.readLine();
}
} catch (IOException e) {
e.printStackTrace();
}
} catch (FileNotFoundException e1) {
e1.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
try {
input = new Scanner(client.getInputStream());
output = new PrintWriter(client.getOutputStream(), true);
}
catch(IOException e) {
e.printStackTrace();
}
}
public void run() {
String target;
String message = "";
target= args[3];
for(int i = 0; i<quotes.size(); i++){
if(quotes.get(i).toUpperCase().contains(target.toUpperCase())){
output.println(quotes.get(i));
}
}
output.println("|");
try {
if (client != null) {
System.out.println("Closing down connection...");
client.close();
}
}
catch(IOException e) {
System.out.println("Unable to disconnect!");
}
}
}
(Thanks to Sir JB Nizet for some modifications and advice) I'm having a problem in target= args[3]; in class ClientHandler3 because I know it makes no sense in overriding. I'm new in this field of programming and I need your help. Please help me figure things out. Thank you!
EDIT
import java.net.*;
import java.util.ArrayList;
import java.util.Scanner;
import java.util.StringTokenizer;
import java.io.*;
public class quotes {
public static InetAddress host;
public static ServerSocket serverSocket;
public static void main(String[] args) throws IOException {
if(args[0].equals("-c")){
Client(args);
}
else if(args[0].equals("-s")){
System.out.println("SERVER KA!!!");
Server(args);
}
}
#SuppressWarnings("resource")
public static void Client(String[] args) throws IOException
String hostname = args[1];
String target, response;
if(hostname.equals("localhost")) host = InetAddress.getLocalHost();
else host = InetAddress.getByName(hostname);
int port = Integer.parseInt(args[2]);
target = args[3];
Socket socket = new Socket(host, port);
Scanner input = new Scanner(System.in);
Scanner networkInput = new Scanner(socket.getInputStream());
PrintWriter networkOutput = new PrintWriter(socket.getOutputStream(), true);
// Set up stream from keyboard entry...
Scanner userEntry = new Scanner(System.in);
networkOutput.println(target);
response = networkInput.nextLine();
while(!response.equals("|")){
// Display server's response to user ...
System.out.println("\n " + response);
response = networkInput.nextLine();
}
}
public static void Server(String[] args) throws IOException {
int port = Integer.parseInt(args[1]);
String file = args[2];
String target = "";
serverSocket = new ServerSocket(port);
do {
// Wait for client...
Socket client = serverSocket.accept();
System.out.println("\nNew client accepted.\n");
ClientHandler3 handler = new ClientHandler3(client, file, target);
handler.start();
}while(true);
}
}
class ClientHandler3 extends Thread {
private Socket client;
private Scanner input;
private PrintWriter output;
private ArrayList<String> quotes;
private String target;
public ClientHandler3(Socket socket, String file, String target) {
// Set up reference to associated socket...
client = socket;
try {
BufferedReader buffer = new BufferedReader(new FileReader(file));
BufferedReader reader = new BufferedReader(new InputStreamReader(client.getInputStream()));
this.target = reader.readLine();
String line = reader.readLine();
try {
int ctr = 0;
quotes = new ArrayList<String>();
while(line != null){
quotes.add(ctr, line);
ctr++;
line = buffer.readLine();
}
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
} catch (FileNotFoundException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
try {
input = new Scanner(client.getInputStream());
output = new PrintWriter(client.getOutputStream(), true);
}
catch(IOException e) {
e.printStackTrace();
}
}
public void run() {
String message = "";
target= input.nextLine();
for(int i = 0; i<quotes.size(); i++){
if(quotes.get(i).toUpperCase().contains(target.toUpperCase())){
output.println(quotes.get(i));
}
}
output.println("|");
try {
if (client != null) {
System.out.println("Closing down connection...");
client.close();
}
}
catch(IOException e) {
System.out.println("Unable to disconnect!");
}
}
}

Set target as a field of ClientHandler3 so you can use it inside run() method.
class ClientHandler3 extends Thread {
...
private String target;
...
and use:
this.target = reader.readLine();
just before
String line = reader.readLine();
line.