Java ObjectInputStream java.io.EOFException

Question

I'm trying to pass data from MySQL to a client using a socket. For a List , I prefer using an array, but if I send an array using this:

InputStream input = client.getInputStream();
        OutputStream output = client.getOutputStream();
        ObjectOutputStream obOutput = new ObjectOutputStream(output);
        Statement statement = dataConnection.createStatement();
        ResultSet modList = statement.executeQuery("SELECT modID, downloads FROM modRegister");
        String[][] mods = new String[3][3];
        int column = 0;
        while (modList.next()) {
            mods[column][1] = modList.getString("modID");
            mods[column][2] = modList.getString("downloads");
            ++column;
        }

        System.out.println(mods[1][1]);

        PrintWriter printClient = new PrintWriter(output);
        printClient.println(column);
        printClient.close();
        obOutput.writeObject(mods);
        obOutput.flush();

and receive it from the client using this:

Socket server = new Socket("localhost", 25566);
    InputStream input = server.getInputStream();
    OutputStream output = server.getOutputStream();
    ObjectInputStream obInput = new ObjectInputStream(input);
    BufferedReader reader = new BufferedReader(new InputStreamReader(input));
    String s;
    int columns = 0;
    while((s = reader.readLine()) != null) {
        columns = Integer.parseInt(s);
        System.out.println(s);
    }
    String [][] mods;
    TimeUnit.SECONDS.sleep(10);
    mods = (String[][])obInput.readObject();

I get an EOFException , even with a time delay. The array IS valid. I tested printing out all the data in it. Here is the exception:

Caused by: java.io.EOFException
at java.io.ObjectInputStream$BlockDataInputStream.peekByte(ObjectInputStream.java:2601)
at java.io.ObjectInputStream.readObject0(ObjectInputStream.java:1319)
at java.io.ObjectInputStream.readObject(ObjectInputStream.java:371)
at layout.MainStoreController.initialize(MainStoreController.java:36)
... 32 more

Answer 1

I suspect that closing the PrintWriter closes the OutputStream it writes to.

PrintWriter printClient = new PrintWriter(output);
printClient.println(column);
printClient.close();

When the stream is closed, then the socket is closed, and the other end will observe End-Of-File as it reads.