Threads

class MyThread extends Thread
{
    public void run()
    {
        try
        {
            processConnection();
        }
        catch(IOException e)
        {
            //empty
        }
    }

    private void processConnection() throws IOException
    { 
        do
        { 
            input = new DataInputStream(client.getInputStream()); 
            message = input.readLine(); 
            pegarCoordenadas(message); 
            update(this.getGraphics(), x, y, a, tam);          
        }
        while (!message.equals(null)); 
    } 

}

MyThread t = new MyThread();
t.start();