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the buffer in server doesn't read the value that client sent

The client sends data (string) to the server, and the server must read it, but in my case the server didn't read the data (value) that the client sent, and I didn't know where is the problem exactly, because normally the steps to read data are all correct in the server side
Client side:
Socket socket = new Socket(address, authenticationServerPort);
username = username + "\n"; // to send username through socket without
String h=getUserInput();
// waiting
// Send the message to the server
// send public key
OutputStream os = socket.getOutputStream();
OutputStreamWriter osw = new OutputStreamWriter(os);
BufferedWriter bw = new BufferedWriter(osw);
System.out.println(h);
bw.write(h);
bw.flush();
System.out.println("Message sent to the Authentication server : "+ h);
Server side:
Socket clientSocket = null;
try {
System.out.println("Server Running");
int serverPort = 8029; // the server port we are using
ServerSocket listenSocket = new ServerSocket(serverPort);
List<BlockChain> resultList = new ArrayList<BlockChain>();
while (true) {
clientSocket = listenSocket.accept();
InputStream is = clientSocket.getInputStream();
System.out.println(is);
InputStreamReader isr = new InputStreamReader(is);
System.out.println(isr);
BufferedReader br = new BufferedReader(isr);
String request = br.readLine();
System.out.println("the msg receving from client is : "+request);
PrintWriter out;
out = new PrintWriter(new BufferedWriter(new OutputStreamWriter(clientSocket.getOutputStream())));
if (clientSocket != null) {
clientSocket.close();
}
}
catch (Exception e) {
e.printStackTrace();// TODO: handle exception
}
}
Someone tell me where is the problem exactly.

Android : Simple HTTPS request and get response

I'm creating a android proxy server and i use this for HTTP request :
Socket socket = new Socket(InetAddress.getByName("perdu.com"), 80);
BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
PrintWriter out = new PrintWriter(socket.getOutputStream());
out.print("GET / HTTP/1.1\r\nHost: perdu.com\r\nConnection: close\r\n\r\n");
out.flush();
I doesn't work for HTTPS request, so my question is : How to replace this for SSL working and get server response ?
Thank you
PS: i'm french, sorry for my english :)

I found solution
SSLSocketFactory factory = (SSLSocketFactory) SSLSocketFactory.getDefault();
SSLSocket socket = (SSLSocket) factory.createSocket(domain, 443);
socket.startHandshake();
BufferedReader in = new BufferedReader(new InpuStreamReader(socket.getInputStream()));
PrintWriter out = new PrintWriter(socket.getOutputStream());

Message not sending to Server from Client - Java

I have a Server-Client program where I send a small messsage to the client using JLabel. When that message is recieved from server that particular client must send a response immediately. But it is not sending any message . Can somebody look at my code and tell me where my mistake is?
//SERVER
void connect_clients()
{
try {
ServerSocket listener = new ServerSocket(7700);
jButton1.setText("Server Running!");
jButton1.setEnabled(false);
while (true) {
socket = listener.accept();
socketList.add(socket);
//socketList.add(listener.accept());
BufferedReader ed = new BufferedReader(new InputStreamReader(socket.getInputStream()));
String tmp = ed.readLine();
System.out.print("I Recieved :"+tmp);
}
}
catch(IOException ex)
{
JOptionPane.showMessageDialog(null,ex);
}
}
//CLIENT
void connect_server() throws IOException
{
try {
// TODO code application logic here
String serverAddress = JOptionPane.showInputDialog(
"Enter IP Address of a machine that is\n" +
"running the date service on port 9090:");
s = new Socket(serverAddress, 7700);
while(true){
BufferedReader input =
new BufferedReader(new InputStreamReader(s.getInputStream()));
String answer = input.readLine();
System.out.println(answer);
if(answer != null)
{
PrintStream pr = new PrintStream(s.getOutputStream());
InputStreamReader rd = new InputStreamReader(System.in);
BufferedReader ed = new BufferedReader(rd);
String temp = ed.readLine();
pr.println(temp);
JOptionPane.showMessageDialog(null,"Answer is not null"); //THIS WORKS
}
}
}
catch (ConnectException e) {
JOptionPane.showMessageDialog(null, e);
}
catch (SocketException e) {
JOptionPane.showMessageDialog(null, e);
}
}

Some points that you missed in your implementation:
the streams and sockets are never closed
in the client i do not see the point of the endless loop
the client should initialize the communication by sending a message via output stream (not to try to read first)
For a simple example the steps should be:
Start sever to listen and once a connection is established to read the message (you did)
The client should sent a message via output stream and close the steams and the socket
The severs should close the streams and the sockect for the established connection
Example:
//Server
socket = listener.accept();
BufferedReader ed = new BufferedReader(new InputStreamReader(socket.getInputStream()));
BufferedWriter pr = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream());
String tmp = ed.readLine();
System.out.print("I Recieved :"+tmp);
String msg = "Message received";
pr.write(msg,0,msg.length());
pr.newLine();
ed.close();
pr.close();
socket.close();
//Client
BufferedWriter pr = new BufferedWriter(new OutputStreamWriter(s.getOutputStream());
BufferedReader input = new BufferedReader(new InputStreamReader(s.getInputStream()));
String sendMessage = "Send Message";
pr.write(msg,0,msg.length());
pr.newLine();
String answer = input.readLine();
System.out.println(answer);
JOptionPane.showMessageDialog(null,"Answer is not null");
input.close();
pr.close();
s.close();
UPDATE
reading from input stream continuously:
BufferedReader input = new BufferedReader(new InputStreamReader(s.getInputStream()));
String line;
while((line=input.readLine())!=null){
//do something with line
}

I will suggest a simple approach where server is sending the hi msg to client.
For server:
//Server
ServerSocket ss=new ServerSocket(3554);
socket = ss.accept();
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
BufferedReader br = new BufferedReader(new InputStreamReader(socket.getOutputStream()));
String msg ="Hi from server"
bw.write(msg);
String msgFromClient=br.readLine();
System.out.println(msgFromClient);
bw.close();
socket.close();
For Client:
//Client
Socket socket=new Socket("localhost",3554)
BufferedReader br = new BufferedReader(new InputStreamReader(socket.getInputStream()));
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(socket.getOutputStream()));
String received = input.readLine();
System.out.println(received);
bw.write("Client recieve :"+received);
br.close();
bw.close();
socket.close();

TCPClient - Send & Receive Response

I'm connecting to a remote TCP Listener that receives a string, and responds with a response.
Going from my Windows 8 Phone App, to a Java Jar. The Jar IS receiving the message, but the Windows 8 Phone App is not getting the response.
C# Code
outputClient.Connect (/IP ADDRESS/, /Port/);
using (Socket sock = outputClient.Client) {
sock.Send (UTF8Encoding.ASCII.GetBytes (broadcastMessage));
var response = new byte[100];
sock.Receive (response);
var str = Encoding.ASCII.GetString (response).Replace ("\0", "");
Console.WriteLine ("[RECV] {0}", str);
} <-- JAVA CODE DOESN'T GET HIT UNTIL THIS LINE IS COMPLETED
Java Code
String clientSentence;
ServerSocket socketServer = new ServerSocket(/* PORT */);
while (true)
{
Socket connectionSocket = socketServer.accept();
connectionSocket.setKeepAlive(true);
BufferedReader inFromClient = new BufferedReader(new InputStreamReader(connectionSocket.getInputStream()));
clientSentence = inFromClient.readLine();
BufferedWriter outToClient = new BufferedWriter(new OutputStreamWriter(connectionSocket.getOutputStream()));
if (clientSentence != null)
{
try
{
JsonObject json = new JsonParser().parse(clientSentence).getAsJsonObject();
String un = json.get("Username").toString();
String uuid = "2c9c79a096ef4d869fb1d1e07469bb41".replaceAll(
"(\\w{8})(\\w{4})(\\w{4})(\\w{4})(\\w{12})",
"$1-$2-$3-$4-$5");
var val = /* Get val */
String response = gson.toJson(val);
outToClient.write(response);
outToClient.newLine();
outToClient.flush();
}
catch (Exception ex)
{
ex.printStackTrace();
outToClient.write(response);
outToClient.newLine();
outToClient.flush();
}
}
connectionSocket.close();
}
A little more explanation: JAVA CODE DOESN'T GET HIT UNTIL THIS LINE IS COMPLETED means that the socket appears to not be sending until using (Socket sock = outputClient.Client) is no longer being used.

I fixed it by replacing the C# code with:
using (TcpClient client = new TcpClient (/IP ADDRESS/, /PORT/))
using (NetworkStream stream = client.GetStream ())
using (StreamReader reader = new StreamReader (stream))
using (StreamWriter writer = new StreamWriter (stream)) {
writer.AutoFlush = true;
foreach (string lineToSend in linesToSend) {
Console.WriteLine ("Sending to server: {0}", lineToSend);
writer.WriteLine (lineToSend);
string lineWeRead = reader.ReadLine ();
Console.WriteLine ("Received from server: {0}", lineWeRead);
Thread.Sleep (2000); // just for effect
}
Console.WriteLine ("Client is disconnecting from server");
}

Connecting to https with Socket

My app is based on Sockets, but regular Sockets, not SSLSockets. Do I have to change all of them to SSL sockets to be able connect to https server?

You must change how the socket is created, by using the SSLSocketFactory, but you don't have to change all your datatypes from Socket to SSLSocket.

Yes i think you have to change for SSL, you can try that :
System.setProperty("javax.net.ssl.trustStore", "clienttrust");
SSLSocketFactory ssf = (SSLSocketFactory) SSLSocketFactory.getDefault();
Socket s = ssf.createSocket("127.0.0.1", 8888);
OutputStream outs = s.getOutputStream();
PrintStream out = new PrintStream(outs);
InputStream ins = s.getInputStream();
BufferedReader in = new BufferedReader(new InputStreamReader(ins));
out.println("Hi,How are u!");
out.println("");
String line = null;
while ((line = in.readLine()) != null) {
System.out.println(line);
}
in.close();
out.close();
it's from : http://www.java2s.com/Tutorial/Java/0490__Security/HttpsSocketClient.htm
Hope it helps !