使用Java帮助实际的TDD

我现在正在寻求帮助,将TDD用作真实世界的例子.大多数节目过于简单,并没有真正展示如何测试和重新考虑更复杂的类.以下是使用线程和网络套接字的代码示例.有人可以解释如何为这样的类创建一个独立的单元测试吗？谢谢.

public class BaseHandler  extends Thread {
  protected Socket mClientSocket;
  protected BufferedReader is = null;
  protected BufferedWriter os = null;
  private Logger mLogger = Logger.getLogger(WebTestController.class.getName());
  protected WebTestController mWebTestController;

  /*********************************************************************
   * 
   * @param piPort - int port to listen on
   */
  public BaseHandler(){
  }


  /*********************************************************************** cleanup
   * Ensure sockets are closed as to not run into bind errors
   */
  protected void cleanup() {
    try {
      if (is != null)
        is.close();
      if (os != null)
        os.close();
      if (mClientSocket != null)
        mClientSocket.close();
    }
    catch (IOException e) {
        e.printStackTrace();
    }
    mLogger.info("cleaning up a socket");
  }

  /***********************************************************************************
   * Sends a message to the current socket
   * @param pMessage
   */
  protected void writeToSocket(String pMessage){
      try {
          os = new BufferedWriter(
            new OutputStreamWriter(mClientSocket.getOutputStream()));

        }
        catch (IOException e) {
          e.printStackTrace();
          cleanup();
          return;
        }
        try {
            os.write(pMessage,pMessage.length());
            os.flush();
        }
        catch (IOException e) {
            e.printStackTrace();
        }
        cleanup();
  }

}