java.lang.NullPointerException PrintWriter
<p>I am getting a NullPointerException when I run my code. I have narrowed down the problem to line 38: when it is commented out the program doesn't give any errors. I just have "test" here for now.</p>

<pre><code>out.println("test")
</code></pre>

<p>The run method is immediately started with the following two lines in another class</p>

<pre><code>Client test = new Client();
test.start();
</code></pre>

<p>And when a button is pressed the following code is executed which runs the sendToServer method</p>

<pre><code>Client test = new Client();
test.sendToServer(cipherText)
</code></pre>

<p>Below is the full code for my Client class.</p>

<pre><code>import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;

public class Client extends Thread{

    String line = "";
    String cipherText = "";

    BufferedReader in;
    PrintWriter out;

    public void run(){
            String serverAddress = "00.000.000.000";
        try{
            Socket socket = new Socket(serverAddress, 8888);
            in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            out = new PrintWriter(socket.getOutputStream(), true);
        }
        catch(IOException e){
            e.printStackTrace();
        }
        while (true) {
            try{
                line = in.readLine();
            }
            catch(IOException e){
                e.printStackTrace();
            }
            System.out.println(line);
        } 
    }

    public void sendToServer(String in) {
        out.println("test");
    }

}
</code></pre>

<p>Thanks for looking, I am still learning java so excuse any obvious mistakes.</p>