invokeLater問題

Question

我遇到了使用invokeLater更新JLabel值的問題。 我有一個運行invokeLater的主函數之外的單獨方法，但是當我單擊搜索按鈕更新值時，它不會在gui的同一實例中更新。 我必須在eclipse中重新啓動gui以獲取更改的值。 我不知道我做錯了什麼，所以任何幫助，非常感謝。 我正在運行此方法threadStart（）;在按鈕的actionListener中。 這裏的方法

private void threadStart() { 
     SwingUtilities.invokeLater(new Runnable() { 
     public void run() { 

      testLabel.setText(CN); 
     } 

這裏是全班作爲參考。

import java.awt.EventQueue; 

import javax.naming.InvalidNameException; 
import javax.naming.ldap.LdapName; 
import javax.swing.JFrame; 
import javax.swing.JButton; 

import java.awt.BorderLayout; 
import java.awt.event.ActionListener; 
import java.awt.event.ActionEvent; 
import java.awt.GridLayout; 

import javax.naming.ldap.LdapName; 
import javax.swing.JTextField; 
import javax.swing.JLabel; 
import javax.swing.SwingUtilities; 
import javax.swing.UIManager; 

import java.awt.Color; 
import java.awt.Font; 
import java.io.BufferedReader; 
import java.io.BufferedWriter; 
import java.io.DataInputStream; 
import java.io.File; 
import java.io.FileInputStream; 
import java.io.FileNotFoundException; 
import java.io.FileReader; 
import java.io.FileWriter; 
import java.io.IOException; 
import java.io.InputStreamReader; 
import java.net.Inet4Address; 
import java.net.UnknownHostException; 
import java.util.regex.Matcher; 
import java.util.regex.Pattern; 

import javax.swing.JTextArea; 
import javax.swing.JTable; 

public class MISControlPanel { 

    JFrame frame; 
    static JTextField textField; 
    private JTextField textField_1; 
    final JTextArea textArea = new JTextArea(); 
    JLabel selectedComputerFromAD = new JLabel("testing"); 
    String sCurrentLine = null; 
    String CN = null; 
    JLabel testLabel = new JLabel("test"); 

    /** 
    * Launch the application. 
    */ 
    public static void main(String[] args) { 

     EventQueue.invokeLater(new Runnable() { 
      public void run() { 
       try { 
        MISControlPanel window = new MISControlPanel(); 
        window.frame.setVisible(true); 

       } catch (Exception e) { 
        e.printStackTrace(); 
       } 
      } 
     }); 
    } 

    /** 
    * Create the application. 
    * 
    * @throws IOException 
    * 
    * @wbp.parser.entryPoint 
    */ 
    public MISControlPanel() throws IOException { 
     initialize(); 
    } 

    /** 
    * Initialize the contents of the frame. 
    * 
    * @throws IOException 
    */ 
    private void initialize() throws IOException { 
     frame = new JFrame(); 
     frame.getContentPane().setBackground(Color.LIGHT_GRAY); 
     frame.getContentPane().setForeground(Color.RED); 
     frame.setBounds(100, 100, 658, 618); 
     frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 
     frame.getContentPane().setLayout(null); 
     frame.setTitle("MIS Advanced Computerers"); 
     frame.setResizable(false); 
     FileWriter fw = new FileWriter("C:\\Users\\anoc5f\\Desktop\\Output.txt"); 
     File tempFile = new File("myTempFile.txt"); 
     JButton searchComputerButton = new JButton("Search"); 
     searchComputerButton.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent e) { 
       threadStart(); 
       String line; 
       BufferedWriter bw = null; 
       BufferedWriter writer = null; 
       try { 
        writer = new BufferedWriter(new FileWriter(tempFile)); 
       } catch (IOException e1) { 
        // TODO Auto-generated catch block 
        e1.printStackTrace(); 
       } 


       String s = null; 

       Process p = null; 
       /* 
       * try { // p = Runtime.getRuntime().exec(
       * "cmd /c start c:\\computerQuery.bat computerName"); } catch 
       * (IOException e1) { // TODO Auto-generated catch block 
       * e1.printStackTrace(); } 
       */ 
       try { 

        p = Runtime.getRuntime().exec("c:\\computerQuery.bat"); 

       } catch (IOException e1) { 

        // TODO Auto-generated catch block 

        e1.printStackTrace(); 

       } 
       StringBuffer sbuffer = new StringBuffer(); 
       BufferedReader in = new BufferedReader(new InputStreamReader(p 
         .getInputStream())); 

       try { 

        while ((line = in.readLine()) != null) { 

         System.out.println(line); 

         // textArea.append(line); 

         String dn = "CN=FDCD111304,OU=Workstations,OU=SIM,OU=Accounts,DC=FL,DC=NET"; 
         LdapName ldapName = new LdapName(dn); 
         String commonName = (String) ldapName.getRdn(
           ldapName.size() - 1).getValue(); 

        } 
        ComputerQuery.sendParam(); 

       } catch (IOException e1) { 

        // TODO Auto-generated catch block 

        e1.printStackTrace(); 

       } catch (InvalidNameException e1) { 
        // TODO Auto-generated catch block 
        e1.printStackTrace(); 
       } finally 

       { 
        try { 
         fw.close(); 

        } 

        catch (IOException e1) { 
         // TODO Auto-generated catch block 
         e1.printStackTrace(); 
        } 
       } 

       try { 

        in.close(); 

       } catch (IOException e1) { 

        // TODO Auto-generated catch block 

        e1.printStackTrace(); 

       } 

       ComputerQuery.sendParam(); 

        SwingUtilities.invokeLater(new Runnable() { 
         public void run() { 
          testLabel.setText(CN); 
         } 
         }); 
      } 
     }); 

     try (BufferedReader br = new BufferedReader(new FileReader(
       "resultofbatch.txt"))) { 

      final Pattern PATTERN = Pattern.compile("CN=([^,]+).*"); 
      try { 
       while ((sCurrentLine = br.readLine()) != null) { 

        String[] tokens = PATTERN.split(","); // This will return 
                  // you a array, 
                  // containing the 
                  // string array 
                  // splitted by what 
                  // you write inside 
                  // it. 
        // should be in your case the split, since they are 
        // seperated by "," 
        // System.out.println(sCurrentLine); 
        CN = sCurrentLine.split("CN=", -1)[1].split(",", -1)[0]; 

        System.out.println(CN); 
        testLabel.setText(CN); 
       } 

      } catch (IOException e1) { 
       // TODO Auto-generated catch block 
       e1.printStackTrace(); 
      } 
     } catch (IOException e2) { 
      // TODO Auto-generated catch block 
      e2.printStackTrace(); 
     } 
     // SwingUtilities.invokeLater(updateCN()); 
     searchComputerButton.setBounds(419, 19, 89, 20); 
     frame.getContentPane().add(searchComputerButton); 

     textField = new JTextField(); 
     textField.setBounds(285, 19, 124, 20); 
     frame.getContentPane().add(textField); 
     textField.setColumns(10); 

     JLabel lblComputerName = new JLabel("Computer Name:"); 
     lblComputerName.setForeground(Color.BLACK); 
     lblComputerName.setFont(new Font("Tahoma", Font.BOLD, 14)); 
     lblComputerName.setBounds(159, 13, 124, 29); 
     frame.getContentPane().add(lblComputerName); 

     JLabel lblSelectedComputer = new JLabel("Selected Computer:"); 
     lblSelectedComputer.setFont(new Font("Tahoma", Font.BOLD, 14)); 
     lblSelectedComputer.setBounds(205, 78, 143, 30); 
     frame.getContentPane().add(lblSelectedComputer); 
     java.net.InetAddress localMachine = null; 
     try { 
      localMachine = java.net.InetAddress.getLocalHost(); 
     } catch (UnknownHostException e2) { 
      // TODO Auto-generated catch block 
      e2.printStackTrace(); 
     } 

     textArea.setBackground(Color.GRAY); 
     textArea.setForeground(Color.WHITE); 
     textArea.setFont(textArea.getFont().deriveFont(Font.BOLD)); 
     textArea.setBounds(10, 387, 632, 191); 
     textArea.setEditable(false); // might cause design view not to come up 
     frame.getContentPane().add(textArea); 

     JButton btnNewButton = new JButton("SSO REPAIR"); 
     btnNewButton.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent e) { 

      } 
     }); 
     btnNewButton.setBounds(36, 183, 132, 23); 
     frame.getContentPane().add(btnNewButton); 

     JLabel lblNewLabel = new JLabel("Batch File Fixes"); 
     lblNewLabel.setFont(new Font("Tahoma", Font.BOLD, 12)); 
     lblNewLabel.setBounds(53, 158, 115, 14); 
     frame.getContentPane().add(lblNewLabel); 

     JLabel lblIpAddress = new JLabel("IP Address:"); 
     lblIpAddress.setFont(new Font("Tahoma", Font.BOLD, 14)); 
     lblIpAddress.setBounds(261, 104, 102, 22); 
     frame.getContentPane().add(lblIpAddress); 

     JLabel label = null; 
     try { 
      label = new JLabel(Inet4Address.getLocalHost().getHostAddress()); // Get 
                       // User 
                       // ID 
     } catch (UnknownHostException e1) { 
      // TODO Auto-generated catch block 
      e1.printStackTrace(); 
     } 
     label.setFont(new Font("Tahoma", Font.BOLD, 14)); 
     label.setForeground(Color.RED); 
     label.setBounds(349, 105, 99, 21); 
     frame.getContentPane().add(label); 

     JLabel lblPcCommunication = new JLabel("PC Communication"); 
     lblPcCommunication.setFont(new Font("Tahoma", Font.BOLD, 12)); 
     lblPcCommunication.setBounds(279, 158, 115, 14); 
     frame.getContentPane().add(lblPcCommunication); 

     JButton btnPingComputer = new JButton("PING"); 

     btnPingComputer.addActionListener(new ActionListener() { 

      public void actionPerformed(ActionEvent arg0) { 
      } 

     }); 

     btnPingComputer.setBounds(306, 183, 64, 23); 
     frame.getContentPane().add(btnPingComputer); 

     JButton remoteAssistanceButton = new JButton(
       "Remote Assistance by PC Name"); 
     remoteAssistanceButton.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent e) { 
      } 
     }); 

     remoteAssistanceButton.setBounds(215, 251, 246, 23); 
     frame.getContentPane().add(remoteAssistanceButton); 

     JButton btnPingIndefinetely = new JButton("PING INDEFINETELY"); 
     btnPingIndefinetely.setBounds(260, 217, 156, 23); 
     frame.getContentPane().add(btnPingIndefinetely); 

     JButton btnRdcByIp = new JButton("RDC by IP Address"); 
     btnRdcByIp.setBounds(261, 353, 156, 23); 
     frame.getContentPane().add(btnRdcByIp); 

     JButton btnRdcByName = new JButton("RDC by PC Name"); 
     btnRdcByName.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent e) { 
      } 
     }); 
     btnRdcByName.setBounds(248, 319, 180, 23); 
     frame.getContentPane().add(btnRdcByName); 

     JLabel lblLoggedInOpid = new JLabel("Logged in OPID:"); 
     lblLoggedInOpid.setFont(new Font("Tahoma", Font.BOLD, 14)); 
     lblLoggedInOpid.setBounds(228, 127, 135, 20); 
     frame.getContentPane().add(lblLoggedInOpid); 

     JLabel lblNewLabel_1 = new JLabel(System.getProperty("user.name") 
       .toUpperCase()); 
     lblNewLabel_1.setFont(new Font("Tahoma", Font.BOLD, 14)); 
     lblNewLabel_1.setForeground(Color.RED); 
     lblNewLabel_1.setBounds(348, 130, 86, 14); 
     frame.getContentPane().add(lblNewLabel_1); 

     JButton btnHiddenShare = new JButton("HIDDEN SHARE"); 
     btnHiddenShare.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent arg0) { 
      } 
     }); 
     btnHiddenShare.setBounds(484, 183, 132, 23); 
     frame.getContentPane().add(btnHiddenShare); 

     JLabel lblAdditionalTools = new JLabel("Tools"); 
     lblAdditionalTools.setFont(new Font("Tahoma", Font.BOLD, 12)); 
     lblAdditionalTools.setBounds(526, 157, 126, 20); 
     frame.getContentPane().add(lblAdditionalTools); 

     JButton btnNewButton_1 = new JButton("Remote Assistance by IP Address"); 
     btnNewButton_1.setBounds(215, 285, 246, 23); 
     frame.getContentPane().add(btnNewButton_1); 

     JButton gpUpdate = new JButton("GP UPDATE"); 
     gpUpdate.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent arg0) { 
      } 
     }); 
     gpUpdate.setBounds(36, 217, 132, 23); 
     frame.getContentPane().add(gpUpdate); 

     JButton btnForced = new JButton("NURMED REG FIX"); 
     btnForced.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent e) { 
      } 
     }); 
     btnForced.setBounds(36, 251, 132, 23); 
     frame.getContentPane().add(btnForced); 

     JButton btnCleaConsoler = new JButton("CLEAR"); 
     btnCleaConsoler.addActionListener(new ActionListener() { 
      public void actionPerformed(ActionEvent arg0) { 
       textArea.setText(""); 
      } 
     }); 
     btnCleaConsoler.setBounds(563, 353, 79, 23); 
     frame.getContentPane().add(btnCleaConsoler); 

     JLabel lblOpid = new JLabel("Find Computer by OPID:"); 
     lblOpid.setFont(new Font("Tahoma", Font.BOLD, 14)); 
     lblOpid.setBounds(104, 53, 180, 14); 
     frame.getContentPane().add(lblOpid); 

     textField_1 = new JTextField(); 
     textField_1.setBounds(285, 50, 124, 20); 
     frame.getContentPane().add(textField_1); 
     textField_1.setColumns(10); 

     JButton btnNewButton_2 = new JButton("Search"); 
     btnNewButton_2.setBounds(419, 50, 89, 23); 
     frame.getContentPane().add(btnNewButton_2); 
     testLabel.setForeground(Color.RED); 
     testLabel.setFont(new Font("Tahoma", Font.BOLD, 14)); 

     testLabel.setBounds(358, 78, 150, 24); 
     frame.getContentPane().add(testLabel); 

    } 
    private void threadStart() { 
      SwingUtilities.invokeLater(new Runnable() { 
      public void run() { 

       testLabel.setText(CN); 
      } 
      }); 
     } 

} 

---

Answer 1

我的建議，再次是，你應該：

• 有您的批處理文件輸出到標準輸出，控制檯，如果你願意。
• 通過從Process中捕獲InputStream和ErrorStream來輸出該陷阱。這些可以通過重定向錯誤流而陷在一起。
• 您應該在後臺線程中執行所有這些操作，例如使用SwingWorker。
• 我想使SwingWorker專門用於類型SwingWorker<Integer, String>，以便它可以「發佈」從其InputStream讀入的字符串，然後它最終可以返回進程的整數退出代碼以確保進程運行正常。

---

例如，假設我在叫test.bat的，簡單地打印出來，傳遞給它的路徑的目錄用戶工作目錄一個bat文件：

test.bat的

dir %1 

你可以從GUI調用這個，並使用上述技術顯示結果。

請注意，我的代碼下面很重要地從MadProgrammer's借用很好的答案，可以在這裏找到：Printing a Java InputStream from a Process。請檢查他的答案，包括他的描述，如果它能幫助你更好地理解正在發生的事情，可以對它進行投票。

另外請務必閱讀Concurrency in Swing瞭解有關如何執行後臺線程以及SwingWorker在Swing GUI中使用的所有詳細信息。

import java.awt.BorderLayout; 
import java.awt.Font; 
import java.awt.GridLayout; 
import java.awt.event.ActionEvent; 
import java.awt.event.KeyEvent; 
import java.beans.PropertyChangeEvent; 
import java.beans.PropertyChangeListener; 
import java.io.BufferedReader; 
import java.io.IOException; 
import java.io.InputStream; 
import java.io.InputStreamReader; 
import java.util.ArrayList; 
import java.util.List; 
import java.util.concurrent.ExecutionException; 
import java.util.function.Consumer; 

import javax.swing.*; 

@SuppressWarnings("serial") 
public class TestBatGui extends JPanel { 
    public static final String BATCH_FILE_PATH = "test.bat"; 
    private JTextArea resultArea = new JTextArea(30, 80); 

    public TestBatGui() { 
     resultArea.setFocusable(false); // not allow user edits 
     resultArea.setFont(new Font(Font.MONOSPACED, Font.PLAIN, 12)); 
     JScrollPane scrollPane = new JScrollPane(resultArea); 
     scrollPane.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_ALWAYS); 
     JPanel buttonPanel = new JPanel(new GridLayout(1, 0, 5, 0)); 
     int keyCode = KeyEvent.VK_H; 
     String path = System.getProperty("user.home"); 
     buttonPanel.add(new JButton(new ShowDirAction("Home Dir", keyCode, path))); 

     keyCode = KeyEvent.VK_W; 
     path = System.getProperty("user.dir"); 
     buttonPanel.add(new JButton(new ShowDirAction("Working Dir", keyCode, 
      path))); 

     setLayout(new BorderLayout()); 
     add(scrollPane, BorderLayout.CENTER); 
     add(buttonPanel, BorderLayout.PAGE_END); 
    } 

    // Action/ActionListener to be used by my buttons 
    private class ShowDirAction extends AbstractAction { 
     private String path; 

     public ShowDirAction(String name, int keyCode, String path) { 
     super(name); 
     putValue(MNEMONIC_KEY, keyCode); 
     this.path = path; 
     } 

     @Override 
     public void actionPerformed(ActionEvent e) { 
     // our SwingWorker 
     BatchFileWorker batchFileWorker = new BatchFileWorker(
       resultArea, BATCH_FILE_PATH, path); 
     // add a listener to respond when the worker is done 
     batchFileWorker.addPropertyChangeListener(new BatchFileWorkerListener()); 
     batchFileWorker.execute(); // execute the worker 
     } 
    } 

    // class to listen for when the worker has completed its work 
    // and then this class extracts the SwingWorker's results via .get() 
    // and does house cleaning if need be. 
    private class BatchFileWorkerListener implements PropertyChangeListener { 
     @Override 
     public void propertyChange(PropertyChangeEvent evt) { 
     if (evt.getNewValue() == SwingWorker.StateValue.DONE) { 
      BatchFileWorker worker = (BatchFileWorker) evt.getSource(); 
      try { 
       // extract the result returned from the worker's doInBackground() method 
       // and most importantly, trap any exceptions thrown 
       int exitValue = worker.get(); 
       String displayText = ""; 
       if (exitValue != 0) { 
        displayText = String.format("Error when running batch, Exit Value: %d", exitValue); 
       } else { 
        displayText = "Batch file ran without error"; 
       } 
       ((Consumer<String>) worker).accept(displayText); 
       ((Consumer<String>) worker).accept("\n"); 
      } catch (InterruptedException e) { 
       e.printStackTrace(); 
      } catch (ExecutionException e) { 
       e.printStackTrace(); 
      } 
     } 
     } 
    } 

    // Our SwingWorker. It's also a Consumer so that outside classes, namely the InputConsumer 
    // can pass the strings that it reads back into the worker via the accept(...) method 
    private class BatchFileWorker extends SwingWorker<Integer, String> implements Consumer<String> { 
     private JTextArea resultArea; 
     private String batchFilePath; 
     private String dirPath; 

     public BatchFileWorker(JTextArea resultArea, String batchFilePath, 
      String dirPath) { 
     this.resultArea = resultArea; 
     this.batchFilePath = batchFilePath; 
     this.dirPath = dirPath; 
     } 

     @Override 
     protected Integer doInBackground() throws Exception { 
     // command list to load into the process builder 
     List<String> commandList = new ArrayList<>(); 
     int exitCode = 0; 
     publish("Getting dir for " + dirPath); 
     commandList.add("cmd"); 
     commandList.add("/c"); 
     commandList.add(batchFilePath); 
     commandList.add(dirPath); 

     // create the process builder 
     ProcessBuilder pBuilder = new ProcessBuilder(commandList); 

     // add the error stream to the input stream so now we have only one stream to handle 
     pBuilder.redirectErrorStream(); 
     Process p = pBuilder.start(); // create our process 
     InputStream is = p.getInputStream(); // get its InputStream and use it 
     InputStreamReader isr = new InputStreamReader(is); // to create a 
     BufferedReader br = new BufferedReader(isr); // BufferedReader 
     InputConsumer consumer = new InputConsumer(br, this); // pass into our consumer object 
     Thread thread = new Thread(consumer); // start this in a background thread 
     thread.start(); 
     exitCode = p.waitFor(); // wait in this thread for the error code 
     thread.join(); // join two threads 
     br.close(); // close the BufferedReader 
     return exitCode; 
     } 

     @Override // this allows our InputConsumer to pass Strings read back into the SwingWorker 
     public void accept(String text) { 
     publish(text); 
     } 

     @Override // published text will be sent here on the EDT, to be placed into the JTextArea 
     protected void process(List<String> chunks) { 
     for (String chunk : chunks) { 
      resultArea.append(chunk + "\n"); 
     } 
     } 
    } 

    // to read in from the BufferedReader, passing text back into its consumer 
    private class InputConsumer implements Runnable { 
     private BufferedReader br; 
     private Consumer<String> consumer; 

     public InputConsumer(BufferedReader br, Consumer<String> consumer) { 
     this.br = br; 
     this.consumer = consumer; 
     } 

     @Override 
     public void run() { 
     String line = null; 
     try { 
      while ((line = br.readLine()) != null) { 
       consumer.accept(line); 
      } 
     } catch (IOException e) { 
      e.printStackTrace(); 
     } 
     } 
    } 

    private static void createAndShowGui() { 
     TestBatGui mainPanel = new TestBatGui(); 

     JFrame frame = new JFrame("TestBatGui"); 
     frame.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE); 
     frame.getContentPane().add(mainPanel); 
     frame.pack(); 
     frame.setLocationByPlatform(true); 
     frame.setVisible(true); 
    } 

    public static void main(String[] args) { 
     SwingUtilities.invokeLater(new Runnable() { 
     public void run() { 
      createAndShowGui(); 
     } 
     }); 
    } 
}