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Socket ObjectInputStream not working after deploy

i'm creating a client(android)/server(java) program and the problem is everything works in LAN but when i put my jar on server it gets stuck on creating the ObjectInputStream object.
here is client piece:
oos = new ObjectOutputStream(s.getOutputStream());
oos.flush();
ois = new ObjectInputStream(s.getInputStream());
and the server:
oos = new ObjectOutputStream(socket.getOutputStream());
oos.flush();
ois = new ObjectInputStream(socket.getInputStream());
so both are equal.
i also tried without the flushes and also switching the ObjectOutputStream creation with the ObjectInputStream in the client.
everything works in LAN. seems pretty logical. but not over internet.
thanks!

Why does order of instantiation seem to matter for input and output streams in Java?

I have the following code that works (please assume that hostname and port are initialized to their proper values, and that Message is a serializable class):
//Example 1 - everything works as expected
Message message = new Message();
try(Socket serverSocket = new Socket(hostname, port))
{
ObjectOutputStream outStream = new ObjectOutputStream(serverSocket.getOutputStream());
outStream.writeObject(message);
outStream.flush();
ObjectInputStream inStream = new ObjectInputStream(serverSocket.getInputStream());
Object response = inStream.readObject();
}
When I move the instantiation of the ObjectInputStream to occur immediately after the ObjectOutputStream instantiation, execution of my application hangs indefinitely:
//Example 2 - client locks up
Message message = new Message();
try(Socket serverSocket = new Socket(hostname, port))
{
ObjectOutputStream outStream = new ObjectOutputStream(serverSocket.getOutputStream());
ObjectInputStream inStream = new ObjectInputStream(serverSocket.getInputStream());
outStream.writeObject(message);
outStream.flush();
Object response = inStream.readObject();
}
I'm looking for a good explanation as to why the second example locks up consistently, and the first example seems to work without a hitch. Strangely, if I use a debugger (Eclipse debugger) on the client and server with this second example, I'm seeing the message make it through to the server, so the writeObject() call is being executed. However, in the client, the debugger gets stuck on the constructor for the ObjectInputStream.

If we go and have a read of the API docs for the ObjectInputStream constructor
The important part:
This constructor will block until the corresponding ObjectOutputStream
has written and flushed the header.

Constructing an ObjectOutputStream writes a header to the stream. Constructing an ObjectInputStream reads it. If both ends construct the ObjectInputStream first, you will therefore get a deadlock.
Solution: construct the ObjectOutputStream first, at both ends, to make sure it can't happen.

Strange behavior of java streaming

I've the necessity to share a streaming of data between two instances as below:
// get EClasses which should be connected
final uk.man.xman.xcore.Parameter source = getParameter(sourceAnchor);
final uk.man.xman.xcore.Parameter target = getParameter(targetAnchor);
// Set data channels
//Output stream
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
DataOutputStream dataOutputStream = new DataOutputStream(new BufferedOutputStream(outputStream));
source.setOutputStream(dataOutputStream);
//Input stream
DataInputStream inpuDataStream = new DataInputStream(new BufferedInputStream(new ByteArrayInputStream(outputStream.toByteArray())));
target.setInputStream(inpuDataStream);
Everything works ok if I write, during those lines of code. Strangely, when I need to use the data channel to write something in another class, like here:
DataOutputStream dataOutputStream = (DataOutputStream) inputParameter.getOutputStream();
System.out.println("WRITE:" + attributes.getValue("value"));
dataOutputStream.writeUTF(attributes.getValue("value"));
dataOutputStream.flush();
I am not able to read, and I really do not know why. Am I missing something?
Thanks for your time

Not sure if that's what you're asking, but you're creating an InputStream that reads from an empty byte array. That doesn't make much sense:
// create an Output stream that will write in memory
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
...
// transform what has been written to the output stream into a byte array.
// Since othing has been written yet, outputStream.toByteArray() returns
// an empty array
DataInputStream inpuDataStream = new DataInputStream(new BufferedInputStream(new ByteArrayInputStream(outputStream.toByteArray())));

Broken pipe using DataInputStream and DataOutputStream and sockets

I set up a client and server sockets. When I use classes ObjectOutputStream and ObjectInputStream and the method readObject/writeObject everything works fine.
It simulates communication with a robot that I know for sure interprets correctly only method
DataOutputStream.writeBytes.
So I set up the new architecture for simulation since the robot is not available for testing on a daily basis.
In the following code where ObjectOutputStream/ObjectInputStream readObject/writeObject were replaced with DataInputStream/DataOutputStream writeBytes and IOutils.toByteArray.
The server socket correctly receives the message but when it tries to write back a response I get a broken pipe as if the connection was closed somewhere.
Notice that I never close sockets or streams because the robot can answer even after 30 seconds.
Any help to make DataOutputStream.writeBytes work would be appreciated.
Here's the non-working code:
Client:
Socket serverSocket = new Socket("server", 9899);
DataOutputStream outputStream = new DataOutputStream(serverSocket.getOutputStream());
//ObjectOutputStream outputStream = new ObjectOutputStream(serverSocket.getOutputStream());
//outputStream.writeObject("\n" + "message" + "\r");
outputStream.writeBytes("\n" + "message" + "\r");
outputStream.flush();
DataInputStream inputStream = new DataInputStream(serverSocket.getInputStream());
//ObjectInputStream inputStream = new ObjectInputStream(serverSocket.getInputStream());
byte [] bytes = IOUtils.toByteArray(inputStream);
String serverResponse = new String(bytes,"UTF-8");
// String serverResponse = (String)inputStream.readObject();
Server:
ServerSocket serverSocket = new ServerSocket(9899);
while (true) {
Socket socket = serverSocket.accept();
//ObjectInputStream inputStream = new ObjectInputStream(socket.getInputStream());
DataInputStream inputStream = new DataInputStream(socket.getInputStream());
byte [] bytes = IOUtils.toByteArray(inputStream);
String message = new String(bytes,"UTF-8");
//String message = (String) inputStream.readObject();
Thread.sleep(15000);
//ObjectOutputStream outputStream = new ObjectOutputStream(socket.getOutputStream());
DataOutputStream outputStream = new DataOutputStream(socket.getOutputStream());
//outputStream.writeObject("server response");
outputStream.writeBytes("server response"); //EXCEPTION THROWN HERE FOR BROKEN PIPE
outputStream.flush();
}
Thanks for your time

IOUtils.toString(InputStream) must read the stream until its end, which would imply that the peer has disconnected. So you can't write to it.
If you're exchanging Strings with data streams you should use writeUTF() and readUTF().
Or read and write lines, with a BufferedReader/Writer.

Data not being read by ServerSocket

I'm trying to work on multiple AVD in Android and sending data between them using Sockets.
Serverside code-snippet:
ServerSocket ss = new ServerSocket(10000);
Log.v("ReceiverTask", "Receiver waiting for requests");
connectedSocket = ss.accept();
ObjectInputStream ois = new ObjectInputStream(connectedSocket.getInputStream());
Object obj = ois.readObject();
ois.close();
ss.close();
Client side code:
Socket socket = new Socket(InetAddress.getByAddress(new byte[]{10, 0, 2, 2}),njr.sendTo());
BufferedOutputStream bos = new BufferedOutputStream(socket.getOutputStream());
ObjectOutputStream oos = new ObjectOutputStream(bos);
oos.writeObject(njr);
Log.d("Client","Object send successfull");
oos.flush();
bos.flush();
oos.reset();
oos.close();
bos.close();
socket.close();
The problem is that The objects that are sent from one AVD (as given by log) is not being received at other AVD. This happens sometimes and not always at a same point. Any hints as to what could be the problem???

use oos.flush() at the end in client.
socket = new Socket(InetAddress.getByAddress(new byte[]{10, 0, 2, 2}),njr.sendTo());
bos = new BufferedOutputStream(socket.getOutputStream());
oos = new ObjectOutputStream(bos);
oos.writeObject(njr);
oos.flush();
oos.close();
Log.d("Client","Object send successfull");

Close the stream after reading, else it will assume that its still open
oos.Close();