systemstatus.java

这是一个用java和xml编写的流媒体服务器管理软件

  }     // end of SystemStatus constructor

  private void sendSNMPStart(OidNode node)
  {
    System.out.println("---TRACE---SystemStatus:sendSNMPStart");

    String requestString = ("START_REQ," + node.getDescriptorString() + "\n");

    VPPTransactionWrapper connection = SNMPApplet.getConnectionInstance();

    try
    {
      String response = connection.request("START_REQ", requestString);

      if ((response == null) || (response.equals("")))
      {
        System.out.println("No response to Start request");

        return;
      }
      else
      {
        try
        {
          decipherResponse("START_REQ", response);
        }
        catch (SAXException e1)
        {
          throw new VPPException(e1.getMessage() + " from SAXException");
        }
        catch (IOException e2)
        {
          throw new VPPException(e2.getMessage() + " from IOException");
        }
      }
    }
    catch (VPPException e)
    {
      VPPTransactionWrapper.showVPPException(e, "Start request failed");
    }
  }

  private void decipherResponse(String requestType, 
          String response) throws SAXException, IOException
  {
    if ((response == null) || (response.trim().equals("")))
    {
      System.out.println("empty response to " + requestType);

      return;
    }

    BufferedReader reader = new BufferedReader(new StringReader(response));

    SAXParserFactory spf = SAXParserFactory.newInstance();
    SAXParser parser = null;
    try
    {
      parser = spf.newSAXParser();
    }
    catch (ParserConfigurationException parsEx)
    {
      parsEx.printStackTrace();
    }
    catch(SAXException saxEx)
    {
      saxEx.printStackTrace();
    }

    parser.parse(new InputSource(reader), handler);
  }

  private void sendSNMPStop(OidNode node)
  {
    System.out.println("---TRACE---SystemStatus:sendSNMPStop");

    String requestString = ("STOP_REQ," + node.getDescriptorString() + "\n");

    System.out.println(requestString);

    VPPTransactionWrapper connection = SNMPApplet.getConnectionInstance();

    try
    {
      String response = connection.request("STOP_REQ", requestString);

      if (response == null)
      {
        System.out.println("No response to STOP_REQ");
      }
      else
      {
        try
        {
          decipherResponse("STOP_REQ", response);
        }
        catch (SAXException e1)
        {
          throw new VPPException(e1.getMessage() + " from SAXException");
        }
        catch (IOException e2)
        {
          throw new VPPException(e2.getMessage() + " from IOException");
        }
      }
    }
    catch (VPPException e)
    {
      VPPTransactionWrapper.showVPPException(e, "Stop request failed");
    }
  }

  /**
   * Checks whether this parent has a child node with this identifier string.
   * 
   * @param parent The parent whose children we are checking.
   * @param identifier The identifier we are checking for.
   * @return The child that contains identifier, or null if no child
   * contains identifier.
   */
  public DefaultMutableTreeNode checkIdentifier(DefaultMutableTreeNode parent, 
          String identifier)
  {
    DefaultMutableTreeNode node = null;

    for (Enumeration e = parent.children(); e.hasMoreElements(); )
    {
      node = (DefaultMutableTreeNode) (e.nextElement());

      if (node == null)
      {
        throw new RuntimeException("Current child is null");
      }

      OidNode nd = (OidNode) node.getUserObject();
      String nodeId = nd.getIdentifier();

      if (nodeId.equals(identifier))
      {
        return node;
      }
    }

    return null;
  }

  /**
   * createNodes : Builds the nodes dynamically
   * @param ip, ip address of the node (or could be hostname)
   * @param port, port of the node
   * @param type, name of the node
   * @param status, represents the status of the node
   */
  public void createNodes(String ip, String port, String type, String status)
  {
    DefaultMutableTreeNode ipNode = null;
    DefaultMutableTreeNode portNode = null;
    DefaultMutableTreeNode statusNode = null;

    ipNode = checkIdentifier(top, ip);

    if (ipNode == null)
    {

      /*
       * create the new IP node
       */
      ipNode = createAndAddChild(top, ip, "HOST:" + ip, OidNode.HOST);

      // make the ip node be displayed at the start
      m_tree.expandPath(new TreePath(top));

      /*
       * create the new port node
       */
      portNode = createAndAddChild(ipNode, port, type + ":" + port, 
              OidNode.PORT);

      ((OidNode) (portNode.getUserObject())).setDescriptorString(ip, port, 
              type);

      /*
       * create the new status node
       */
      createAndAddChild(portNode, null, status, OidNode.STATUS);

      updateMessage(type, port, status, ip);
    }
    else
    {
      OidNode userObject = null;

      /*
       * MATCH FOUND FOR IP
       */
      portNode = checkIdentifier(ipNode, port);

      if (portNode == null)
      {

        /*
         * create the new port node
         */
        portNode = createAndAddChild(ipNode, port, type + ":" + port, 
                OidNode.PORT);

        ((OidNode) (portNode.getUserObject())).setDescriptorString(ip, port, 
                type);

        /*
         * create the new status node
         */
        statusNode = createAndAddChild(portNode, null, status, 
                OidNode.STATUS);
        userObject = (OidNode) (statusNode.getUserObject());

        updateMessage(type, port, status, ip);
      }
      else
      {

        statusNode = (DefaultMutableTreeNode) (portNode.getChildAt(0));
        userObject = (OidNode) statusNode.getUserObject();

        /*
         * Check if the status has changed
         */
        String oldStatus = userObject.toString();

        if (oldStatus.equals(status))
        {
          return;
        }

        /*
         * They are Different
         */
        userObject.setDisplayString(status);
        System.out.println("\n status.setName() = " + userObject);

        if (statusNode != null)
        {
          m_model.nodeChanged(statusNode);
        }

        if (portNode != null)
        {
          m_model.nodeChanged(portNode);
        }

        if (ipNode != null)
        {
          m_model.nodeChanged(ipNode);
        }

        updateMessage(type, port, status, ip);
      }
    }
  }


  /**
   * 
   * @param parent
   * @param id
   * @param displayString
   * @param type ROOT, HOST, PORT, or STATUS
   * 
   * @return
   */
  private DefaultMutableTreeNode createAndAddChild(DefaultMutableTreeNode parent, 
          String id, String displayString, int type)
  {
    OidNode oNode = new OidNode(id, parent, type);

    oNode.setDisplayString(displayString);

    DefaultMutableTreeNode childNode = new DefaultMutableTreeNode(oNode);

    m_model.insertNodeInto(childNode, parent, 0);

    return childNode;

  }


  /**
   * updateMessage : Update the GUI with the new messages received
   */
  public void updateMessage(String type, String port, String status, 
          String ip)
  {
    java.util.Calendar cal;
    String textStr = " ";
    String redString = " ";
    String DATE_FORMAT = "MM/dd/yyyy HH:mm:ss";
    java.text.SimpleDateFormat sdf;

    cal = Calendar.getInstance(TimeZone.getDefault());

    sdf = new java.text.SimpleDateFormat(DATE_FORMAT);

    sdf.setTimeZone(TimeZone.getDefault());

    /*
     * Display the latest message in the text field of the GUI screen
     */
    m_display.setText("Server name : " + type + " : " + port 
                      + " ,  Status : " + status);

    textStr = messagePane.getText();

    /*
     * Append the new message in the message pane of the GUI screen
     */
    messagePane.setText(sdf.format(cal.getTime()) + " --> " + ip + "   " 
            + type + " : " + port + "  " + status + "\n" + textStr);
  }


  /**
   * interface to the SNMP manager
   * @param ip The IP address of the device that changed.
   * @param port The port number of the device that changed.
   * @param type The type of the device that changed, for example "ms" or "fs".
   * @param status The new status of the device that changed,
   * for example "active" or "inactive".
   */
  public void changeEvent(String ip, String port, String type, String status)
  {
    createNodes(ip, port, type, status);
  }

  public void stop()
  {
    try
    {
      SNMPApplet.getConnectionInstance().close();
    }
    catch (VPPException e)
    {
      System.out.println("Error closing connection: " + e.getMessage());
    }

    run = false;

    if ((theApplet == null) || (theApplet.isStandalone))
    {

      // uncomment for debug
      // System.out.println("CALLING SYSTEM EXIT");
      System.exit(0);
    }

    // uncomment for debug
    // System.out.println("STOPPING APPLET");
    theApplet.stop();
  }

  public void start() throws SNMPClientException
  {
    run = true;

    VPPTransactionWrapper connection = SNMPApplet.getConnectionInstance();
    String response;
    String request, message;

    request = "CONFIG_REQ";

    while (run)
    {
      try
      {
        message = request + "," + versionNumber + ",0\n";

        // uncomment for debugging
        // System.out.println("Sending request " + request + message);
        synchronized (this)
        {
          response = connection.request(request, message);
        }
      }
      catch (VPPException e)
      {
        VPPTransactionWrapper.showVPPException(e, "Status request failed");

        return;
      }

      // if the connection timed out or the response could not be gotten for
      // some other reason, the response will be null.
      if (response == null)
      {
        System.out.println("---TRACE---SNMPApplet:init - no response to " 
                           + request + " " + message);
      }
      else
      {

        try
        {
          decipherResponse(request, response);
        }
        catch (SAXException e1)
        {
          throw new SNMPClientException(e1.getMessage() 
                  + " from SAXException");
        }
        catch (IOException e2)
        {
          throw new SNMPClientException(e2.getMessage() 
                  + " from IOException");
        }

        try
        {
          int time = 500;

          // uncomment for debugging
          // System.out.println("Sleeping for " + time + " ms");
          Thread.sleep(time);
        }
        catch (InterruptedException e)
        {
          throw new SNMPClientException("sleep unexpectedly interrupted: " 
                  + e.getMessage());
        }
      }         // end else (response received)
    }
  }