applet - Java 小程序 RuntimeException : java. lang.NoClassDefFoundError: javax/mail/Authenticator-6ren

applet - Java 小程序 RuntimeException : java. lang.NoClassDefFoundError: javax/mail/Authenticator

转载作者：塔克拉玛干更新时间：2023-11-02 08:24:48

我已经编写了我的第一个 Java 小程序，但在将它部署到我的 Web 服务器上时出现错误。我的小程序使用了几个额外的 jar 文件，例如 javaMail mail.jar、smtp.jar、mailapi.jar 等。当我尝试在网络浏览器中显示我的小程序时，我在错误对话框中得到这样的信息:

java.lang.RuntimeException: java.lang.NoClassDefFoundError: javax/mail/Authenticator
..
Caused by: java.lang.NoClassDefFoundError: javax/mail/Authenticator
    ... 20 more

我不太擅长网络应用程序，也不确定是什么原因导致了这个错误。根据信息，我假设我的小程序无法加载库。那么我该如何解决呢？我的服务器上的/lib 目录中有这些库。所有其他文件都在主目录中。我的 HTML 文件如下:

<HTML>
<HEAD>
   <TITLE>TPSA Speed Test</TITLE>
</HEAD>
<BODY>
<P>
<APPLET code="speedtester_pkg/AppletMain.class" archive="SpeedTester.jar" width=440     height=600></APPLET>
</P>
</BODY>
</HTML>

我还尝试使用具有相同效果的 JNLP 将我的小程序加载到 Web 浏览器。我试图找到一些方法在 HTML 文件中指向这些库，但我没有成功(试图在 JNLP 文件中添加另一个 jar 归档行或 nativelib)。我还尝试将这些库与我的小程序类一起添加到 jar 文件中，但这也无济于事。

这是我使用 javaMail 的代码(接近代码末尾的 sendTestResults() 方法):

/*
 * AppletMain.java
 */
package speedtester_pkg;

import java.awt.*;
import java.beans.*;
import java.io.*;
import java.util.*;
import java.util.logging.*;
import javax.swing.*;
import javax.mail.Address;
import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.PasswordAuthentication;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

public class AppletMain extends javax.swing.JApplet implements PropertyChangeListener{

private ArrayList<String> customerFields;
private DataReader dataReader;
private Test test;
private FileHandler fh;
private ProgressBarTask progressBarTask;
private JTextField[] customerData;
private String speed, cpuLoad, NICspeed, testTime;
private int timeDef = 60;
    /**
 * The input file directory
 */
//    public String directory = "C:\\Documents and Settings\\Administrator\\Pulpit\\";
public String filename = "speedtestData.txt";
/**
 * Input file should be  a simple "*.txt" file named "speedtestData.txt"
 */
public File file;
// mail sending data
/**
 * TO DO encrypt mailing data
 */
private String smtpHost = "smtp.gmail.com",
        username = "myUserName",
        password = "myPassword";

private int port = 465; // TLS 587/ SSL 465


/** Initializes the applet Applet */
@Override
public void init() {
    try {
        java.awt.EventQueue.invokeAndWait(new Runnable() {
            public void run() {
                createGUI();
            }
        });
    } catch (Exception ex) {
        ex.printStackTrace();
    }
}

/** This method is called from within the init() method to
 * initialize the form.
 * WARNING: Do NOT modify this code. The content of this method is
 * always regenerated by the Form Editor.
 */
@SuppressWarnings("unchecked")
// <editor-fold defaultstate="collapsed" desc="Generated Code">                          
private void initComponents() {

    infoPanel = new javax.swing.JPanel();
    labelLogo = new javax.swing.JLabel();
    labelTitle = new javax.swing.JLabel();
    labelLinkSpeed = new javax.swing.JLabel();
    labelProcessorLoad = new javax.swing.JLabel();
    labelNIC = new javax.swing.JLabel();
    buttonStart = new javax.swing.JButton();
    jLabel4 = new javax.swing.JLabel();
    jLabel5 = new javax.swing.JLabel();
    jLabel6 = new javax.swing.JLabel();
    jProgressBar = new javax.swing.JProgressBar();
    formPanel = new javax.swing.JPanel();
    jLabel8 = new javax.swing.JLabel();
    buttonSend = new javax.swing.JButton();
    labelForm = new javax.swing.JLabel();
    infoLabel = new javax.swing.JLabel();
    jScrollPane = new javax.swing.JScrollPane();
    commentText = new javax.swing.JTextArea();

    labelTitle.setFont(new java.awt.Font("Tahoma", 1, 14)); // NOI18N
    labelTitle.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
    labelTitle.setText("Link Speed Test");

    labelLinkSpeed.setFont(new java.awt.Font("Tahoma", 1, 24)); // NOI18N
    labelLinkSpeed.setHorizontalAlignment(javax.swing.SwingConstants.RIGHT);

    labelProcessorLoad.setFont(new java.awt.Font("Tahoma", 1, 18)); // NOI18N
    labelProcessorLoad.setHorizontalAlignment(javax.swing.SwingConstants.RIGHT);

    labelNIC.setFont(new java.awt.Font("Tahoma", 0, 14)); // NOI18N
    labelNIC.setHorizontalAlignment(javax.swing.SwingConstants.RIGHT);

    buttonStart.setText("Start");
    buttonStart.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            buttonStartActionPerformed(evt);
        }
    });

    jLabel4.setFont(new java.awt.Font("Tahoma", 0, 12)); // NOI18N
    jLabel4.setText("Szybkość łącza:");

    jLabel5.setFont(new java.awt.Font("Tahoma", 0, 12)); // NOI18N
    jLabel5.setText("Obciążenie procesora:");

    jLabel6.setFont(new java.awt.Font("Tahoma", 0, 12)); // NOI18N
    jLabel6.setText("Szybkość karty sieciowej:");

    javax.swing.GroupLayout infoPanelLayout = new javax.swing.GroupLayout(infoPanel);
    infoPanel.setLayout(infoPanelLayout);
    infoPanelLayout.setHorizontalGroup(
        infoPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, infoPanelLayout.createSequentialGroup()
            .addComponent(labelLogo, javax.swing.GroupLayout.PREFERRED_SIZE, 100, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addGroup(infoPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                .addGroup(infoPanelLayout.createSequentialGroup()
                    .addGroup(infoPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addComponent(jLabel5)
                        .addComponent(jLabel6)
                        .addComponent(jLabel4))
                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                    .addGroup(infoPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addComponent(labelLinkSpeed, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, 146, Short.MAX_VALUE)
                        .addComponent(labelProcessorLoad, javax.swing.GroupLayout.DEFAULT_SIZE, 146, Short.MAX_VALUE)
                        .addComponent(labelNIC, javax.swing.GroupLayout.DEFAULT_SIZE, 146, Short.MAX_VALUE)))
                .addComponent(labelTitle, javax.swing.GroupLayout.Alignment.LEADING, javax.swing.GroupLayout.PREFERRED_SIZE, 289, javax.swing.GroupLayout.PREFERRED_SIZE))
            .addGap(22, 22, 22))
        .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, infoPanelLayout.createSequentialGroup()
            .addContainerGap(352, Short.MAX_VALUE)
            .addComponent(buttonStart, javax.swing.GroupLayout.PREFERRED_SIZE, 65, javax.swing.GroupLayout.PREFERRED_SIZE))
    );
    infoPanelLayout.setVerticalGroup(
        infoPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGroup(infoPanelLayout.createSequentialGroup()
            .addContainerGap()
            .addGroup(infoPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING, false)
                .addGroup(javax.swing.GroupLayout.Alignment.TRAILING, infoPanelLayout.createSequentialGroup()
                    .addComponent(labelTitle)
                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                    .addGroup(infoPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.TRAILING)
                        .addComponent(jLabel4, javax.swing.GroupLayout.PREFERRED_SIZE, 31, javax.swing.GroupLayout.PREFERRED_SIZE)
                        .addComponent(labelLinkSpeed, javax.swing.GroupLayout.DEFAULT_SIZE, 31, Short.MAX_VALUE))
                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                    .addGroup(infoPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addComponent(jLabel5)
                        .addComponent(labelProcessorLoad, javax.swing.GroupLayout.PREFERRED_SIZE, 21, javax.swing.GroupLayout.PREFERRED_SIZE))
                    .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
                    .addGroup(infoPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                        .addComponent(jLabel6)
                        .addComponent(labelNIC, javax.swing.GroupLayout.PREFERRED_SIZE, 18, javax.swing.GroupLayout.PREFERRED_SIZE))
                    .addGap(6, 6, 6))
                .addGroup(infoPanelLayout.createSequentialGroup()
                    .addGap(16, 16, 16)
                    .addComponent(labelLogo, javax.swing.GroupLayout.PREFERRED_SIZE, 100, javax.swing.GroupLayout.PREFERRED_SIZE)))
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED, 8, Short.MAX_VALUE)
            .addComponent(buttonStart)
            .addContainerGap())
    );

    javax.swing.GroupLayout formPanelLayout = new javax.swing.GroupLayout(formPanel);
    formPanel.setLayout(formPanelLayout);
    formPanelLayout.setHorizontalGroup(
        formPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGap(0, 417, Short.MAX_VALUE)
    );
    formPanelLayout.setVerticalGroup(
        formPanelLayout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGap(0, 127, Short.MAX_VALUE)
    );

    jLabel8.setText("Uwagi:");

    buttonSend.setText("Wyślij");
    buttonSend.addActionListener(new java.awt.event.ActionListener() {
        public void actionPerformed(java.awt.event.ActionEvent evt) {
            buttonSendActionPerformed(evt);
        }
    });

    labelForm.setFont(new java.awt.Font("Tahoma", 0, 14));
    labelForm.setText("Formularz:");

    infoLabel.setFont(new java.awt.Font("Tahoma", 1, 12)); // NOI18N
    infoLabel.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
    infoLabel.setText("Kliknij przycisk \"Start\" aby rozpocząć test");

    commentText.setColumns(20);
    commentText.setRows(5);
    jScrollPane.setViewportView(commentText);

    javax.swing.GroupLayout layout = new javax.swing.GroupLayout(getContentPane());
    getContentPane().setLayout(layout);
    layout.setHorizontalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGap(0, 437, Short.MAX_VALUE)
        .addGap(0, 437, Short.MAX_VALUE)
        .addGroup(layout.createSequentialGroup()
            .addContainerGap()
            .addGroup(layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
                .addComponent(jScrollPane, javax.swing.GroupLayout.DEFAULT_SIZE, 417, Short.MAX_VALUE)
                .addComponent(formPanel, javax.swing.GroupLayout.Alignment.TRAILING, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(infoLabel, javax.swing.GroupLayout.DEFAULT_SIZE, 417, Short.MAX_VALUE)
                .addComponent(jLabel8, javax.swing.GroupLayout.PREFERRED_SIZE, 42, javax.swing.GroupLayout.PREFERRED_SIZE)
                .addComponent(jProgressBar, javax.swing.GroupLayout.DEFAULT_SIZE, 417, Short.MAX_VALUE)
                .addComponent(infoPanel, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE)
                .addComponent(labelForm)
                .addComponent(buttonSend, javax.swing.GroupLayout.Alignment.TRAILING))
            .addContainerGap())
    );
    layout.setVerticalGroup(
        layout.createParallelGroup(javax.swing.GroupLayout.Alignment.LEADING)
        .addGap(0, 572, Short.MAX_VALUE)
        .addGap(0, 572, Short.MAX_VALUE)
        .addGroup(layout.createSequentialGroup()
            .addComponent(infoPanel, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(jProgressBar, javax.swing.GroupLayout.PREFERRED_SIZE, 19, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(infoLabel, javax.swing.GroupLayout.PREFERRED_SIZE, 29, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.UNRELATED)
            .addComponent(labelForm)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(formPanel, javax.swing.GroupLayout.PREFERRED_SIZE, javax.swing.GroupLayout.DEFAULT_SIZE, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(jLabel8, javax.swing.GroupLayout.PREFERRED_SIZE, 16, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(jScrollPane, javax.swing.GroupLayout.PREFERRED_SIZE, 109, javax.swing.GroupLayout.PREFERRED_SIZE)
            .addPreferredGap(javax.swing.LayoutStyle.ComponentPlacement.RELATED)
            .addComponent(buttonSend)
            .addContainerGap(javax.swing.GroupLayout.DEFAULT_SIZE, Short.MAX_VALUE))
    );
}// </editor-fold>                        

public void createGUI()
{
    try {
        dataReader = new DataReader(this);
        dataReader.read();
        customerFields = dataReader.getCustomerFields();
        testTime = String.valueOf(dataReader.getTestTime());
        initComponents();
        generateCustomerForm();
        test = new Test(this, dataReader.getDownloadURLs(), dataReader.getTestTime());
    } catch (ClassNotFoundException ex) {
        Logger.getLogger(AppletMain.class.getName()).log(Level.SEVERE, null, ex);
    } catch (InstantiationException ex) {
        Logger.getLogger(AppletMain.class.getName()).log(Level.SEVERE, null, ex);
    } catch (IllegalAccessException ex) {
        Logger.getLogger(AppletMain.class.getName()).log(Level.SEVERE, null, ex);
    } catch (UnsupportedLookAndFeelException ex) {
        Logger.getLogger(AppletMain.class.getName()).log(Level.SEVERE, null, ex);
    } catch (FileNotFoundException ex) {
        Logger.getLogger(AppletMain.class.getName()).log(Level.SEVERE, null, ex);
    }


}

private void buttonStartActionPerformed(java.awt.event.ActionEvent evt) {                                            
    buttonStart.setEnabled(false);
    infoLabel.setText("Poczekaj do końca testu...");
    progressBarTask = new ProgressBarTask(this);
            infoLabel.setText("progress bar");
    progressBarTask.addPropertyChangeListener(this);
    progressBarTask.execute();
    Thread testThread = new Thread(this.test);
    testThread.start();
    System.out.println("Test thread \"" + testThread.getName() + "\" started.");
}                                           

private void buttonSendActionPerformed(java.awt.event.ActionEvent evt) {                                           
    try {
        sendTestResults();
    } catch (MessagingException ex) {
        Logger.getLogger(AppletMain.class.getName()).log(Level.SEVERE, null, ex);
    } catch (UnsupportedEncodingException ex) {
        Logger.getLogger(AppletMain.class.getName()).log(Level.SEVERE, null, ex);
    }

}                                          

private void generateCustomerForm() throws ClassNotFoundException, InstantiationException, IllegalAccessException, UnsupportedLookAndFeelException
{
    UIManager.setLookAndFeel(UIManager.getCrossPlatformLookAndFeelClassName());
    //correcting auto-generated layout
    jLabel8.setFont(new java.awt.Font("Tahoma", 0, 11));
    labelProcessorLoad.setAlignmentX(RIGHT_ALIGNMENT);
    labelLogo.setIcon(new ImageIcon(getImage(getDocumentBase(), "orange.jpeg")));

    //gereate JLabels and JTextFields read from file
    GridBagLayout gridBagLayout = new GridBagLayout();
    GridBagConstraints gbc = new GridBagConstraints();
    formPanel.setLayout(gridBagLayout);
    customerData = new JTextField[customerFields.size()];

    for(int i=0; i<customerFields.size(); i++)
    {
        JLabel l = new JLabel(customerFields.get(i));
        l.setFont(new java.awt.Font("Tahoma", 0, 11));
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.gridx=0;
        gbc.gridy=i;
        gbc.weightx = 0.5;
        gbc.weighty = 0.5;
        formPanel.add(l, gbc);

        JTextField t = new JTextField();
        t.setFont(new java.awt.Font("Tahoma", 0, 11));
        gbc.fill = GridBagConstraints.HORIZONTAL;
        gbc.gridx=1;
        gbc.gridy=i;
        gbc.weightx = 0.5;
        gbc.weighty = 0.5;
        formPanel.add(t, gbc);
        customerData[i] = t;
    }

}

/**
 * Invoked when task's progress property changes.
 */
public void propertyChange(PropertyChangeEvent evt) {
    if (evt.getPropertyName().equals("progress")) {
        int progress = (Integer) evt.getNewValue();
        jProgressBar.setValue(progress);
    }
}

public void setLabelProcessorLoad(String text)
{
    labelProcessorLoad.setText(text);
}

public void setLabelLinkSpeed(String text)
{
    labelLinkSpeed.setText(text);
}

public void setLabelNIC(String text)
{
    labelNIC.setText(text);
}

public JProgressBar getProgressBar()
{
    return jProgressBar;
}

public JButton getButtonStart()
{
    return buttonStart;
}

public Test getTest()
{
    return this.test;
}

public void setNICspeed(String NICspeed) {
    this.NICspeed = NICspeed;
}

public void setCpuLoad(String cpuLoad) {
    this.cpuLoad = cpuLoad;
}

public void setSpeed(String speed) {
    this.speed = speed;
}

public JLabel getInfoLabel() {
    return infoLabel;
}
/**
 * Prepares e-mail message for sending via google SMTP protocol with SSL
 */
private void sendTestResults() throws MessagingException, UnsupportedEncodingException{
    Properties props = new Properties();
    props.put("mail.smtp.host", "smtp.gmail.com");
    props.put("mail.smtp.socketFactory.port", "465");
    props.put("mail.smtp.socketFactory.class",
            "javax.net.ssl.SSLSocketFactory");
    props.put("mail.smtp.auth", "true");
    props.put("mail.smtp.port", "465");

    Session session = Session.getDefaultInstance(props,
    new javax.mail.Authenticator() {
        protected PasswordAuthentication getPasswordAuthentication() {
            return new PasswordAuthentication(username,password);
        }
    });

    MimeMessage message = new MimeMessage(session);
    //Setting message fields
    Address toAddress = new InternetAddress(dataReader.getMail(), "SpeedTest crew");
    message.addRecipient(Message.RecipientType.TO, toAddress);
    message.setSubject("SpeedTest");

    message.setText(prepareMailText(), "UTF8");

    Transport.send(message);
    infoLabel.setText("Wiadomość z wynikami testu została wysłana pomyślnie");
    System.out.println("Mail sent.");
}

/**
 * Gets all test results and customer data and prepares mail content
 * @return the content of e-mail body
 */
private String prepareMailText()
{
    String messageContentHeader = "Prędkość pobierania\t" + "Obciążenie procesora\t" +
            "Szybkość łącza karty sieciowej\t" + "Czas trwania testu\t";
    String messageContent = speed + "\t"+ cpuLoad + "\t" + NICspeed + "\t" + testTime + "\t";

    for(int j=0;j<customerData.length;j++)
    {
        messageContentHeader += customerFields.get(j) + "\t";
        messageContent += customerData[j].getText() + "\t";
    }
    messageContentHeader += "Uwagi";
    messageContent += commentText.getText();
    String messageText = messageContentHeader + "\n" + messageContent;
    return messageText;
}

// Variables declaration - do not modify                     
private javax.swing.JButton buttonSend;
private javax.swing.JButton buttonStart;
private javax.swing.JTextArea commentText;
private javax.swing.JPanel formPanel;
private javax.swing.JLabel infoLabel;
private javax.swing.JPanel infoPanel;
private javax.swing.JLabel jLabel4;
private javax.swing.JLabel jLabel5;
private javax.swing.JLabel jLabel6;
private javax.swing.JLabel jLabel8;
private javax.swing.JProgressBar jProgressBar;
private javax.swing.JScrollPane jScrollPane;
private javax.swing.JLabel labelForm;
private javax.swing.JLabel labelLinkSpeed;
private javax.swing.JLabel labelLogo;
private javax.swing.JLabel labelNIC;
private javax.swing.JLabel labelProcessorLoad;
private javax.swing.JLabel labelTitle;
// End of variables declaration                   



}

我在使用其他库(如 Sigar.jar)时也遇到了问题，但我想它会以类似的方式解决。

有人有好的建议吗？

最佳答案

有必要将包含 javax.mail 包的 Jar 添加到小程序的运行时类路径中。要实现这一点(一种方法是)将该 Jar 放在同一个位置 SpeedTester.jar 并更改存档属性:

archive="SpeedTester.jar"

..至:

archive="SpeedTester.jar,mail.jar"

更新1

改变整个小程序元素:

来自

<APPLET 
    code="speedtester_pkg/AppletMain.class" 
    archive="SpeedTester.jar" 
    width=440     
    height=600>
</APPLET>

至

<APPLET 
    code="speedtester_pkg.AppletMain" 
    archive="SpeedTester.jar,mail.jar" 
    width=440     
    height=600>
</APPLET>

假设小程序类的包为speedtester_pkg，小程序名为AppletMain。代码属性应该是小程序类的完全限定名称，而不是路径/文件名。

更新2

以上建议重新。 mail.jar 不考虑从 Test、DataReader 或 ProgressBarTask(或他们加载的类)。 “冲洗并重复”该建议，以使用存档属性将额外的 API 添加到运行时类路径。

注意事项

似乎其他答案都指的是网络应用程序。那完全是服务器端的。对于这样的网络应用程序，将 Jars 放入 lib 是有意义的。 OTOH 小程序只能通过将 Jar 的 URL 复制/粘贴到浏览器地址栏并点击 enter 来访问可用的 Jar。

事实上，使用 Jar 的代码库和 href 的组合，就是一个很好的“酸性测试”，可以判断小程序是否能够访问存档。

关于applet - Java 小程序 RuntimeException : java. lang.NoClassDefFoundError: javax/mail/Authenticator，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/7428660/

文章推荐： Android Room LiveData 选择查询参数

文章推荐： ios - 将 ISO6801 日期转换为 NSDate 以进行 RestKit 对象映射

文章推荐： iphone - UIFont 大小 : half point sizes possible?

noclassdeffounderror - 为什么我从我的代码中得到这个 NoClassDefFoundError？
我一直在尝试在我的代码中使用 Jar 文件作为库，并且它编译得很好。但是，在运行时，我不断收到 NoClassDefFoundError信息。为什么会这样？我也在编译路径和运行时路径中包含了 Jar
noclassdeffounderror - kafka NoClassDefFoundError kafka/Kafka
关于Apache-Kafka messaging queue . 我已经从 Kafka 下载页面下载了 Apache Kafka。我已将其提取到 /opt/apache/installed/kafka
noclassdeffounderror - 创建 DefaultHttpClient 导致 NoClassDefFoundError
我正在尝试使用 Apache DefaultHttpClient 来执行 JSON POST 请求，当我尝试实例化它时它给我一个 NoClassDefFound 错误。 HttpClient clie
java - 在真实设备上运行应用程序时出现 NoClassDefFoundError，但在模拟器上运行时不会出现 NoClassDefFoundError
当我在模拟器(Nexus One API 22)上测试我的应用程序时，它运行顺利，没有失败。然而，当我在自己的个人手机(三星 Galaxy S5，Android 版本 5.0)上测试该应用程序时，它崩
java - jython java.lang.NoClassDefFoundError : java. lang.NoClassDefFoundError:org/json/simple/JSONObject
我需要在python中使用java代码来减少，所以我选择了Jython。一段时间后，我设法弄清楚了如何运行我的代码，但我遇到了最奇怪的事情。当我写作时 from vohmm.corpus import
Caused by: java.lang.NoClassDefFoundError: org/mybatis/spring/mapper/MapperScannerConfigurer(原因：java.lang.NoClassDefFoundError：org/mybatis/spring/mapper/MapperScannerConfigurer)
这是我的mybatis配置。这是我的pom.xml。。当我运行项目时，它显示了错误的原因：org/mybatis/spring/mapper/MapperScannerConfigurer.有没有人能
Gradle NoClassDefFoundError
所以我正在尝试构建一个简单的gradle应用，当我运行它时， geb.ConfigurationLoader$UnableToLoadException: Unable to load configu
Java动态加载JAR : NoClassDefFoundError
假设我有一个主类应用程序，它使用 URLClassLoader 加载子目录 plugins 中的所有 jar: public class App(){ public static void m
Netbeans NoClassDefFoundError
我在尝试运行 Netbeans (7.2) 时遇到一个反复出现的错误，上次遇到它时，我发现某个地方可以将所有文件移动到一个新项目。这可能会奏效，但我的项目的规模让这很麻烦。这是踪迹... Except
使用maven的Java NoClassDefFoundError
这个问题已经有答案了: Including all the jars in a directory within the Java classpath (25 个回答) 已关闭 6 年前。我得到一个
Java NoClassDefFoundError
在这里，我正在下载网页源代码，然后将其存储在文本文件中。然后我读取该文件并将其与正则表达式匹配以搜索特定字符串。没有编译器错误。 Exception in thread "main" java.la
Java NoClassDefFoundError
我正在一个“大”的 Maven/Java 项目中工作，无法理解运行应用程序时遇到的错误(它编译正常)。我得到的错误代码是: java.lang.NoClassDefFoundError: Could
Java NoClassDefFoundError
对于学校的作业，我需要创建一个类 Blender 来实现一些预定义的东西。我收到了一个 JAR 文件 imagecompositor.jar，它可以完成所有操作并使用 Blender 类。 JAR 文
java - NoClassDefFoundError
我遇到了一个问题，即抛出 NoClasDefFoundError。这让我感到困惑，因为我正在使用接口(interface)，并且没有类定义应该可用。我已经阅读了一些指向类路径的帖子，但我不认为这是这里
java - NoClassDefFoundError
我正在使用 hibernate，在使用 hibernate Connection 时出现如下错误 java.lang.NoClassDefFoundError: Could not initializ
安卓:NoClassDefFounderror
我有一个使用 SubVersion 的 Android 项目。我使用 Subclipse 将项目导入我的 Eclipse Wordspace。现在我有一个问题: java.lang.NoClass
Java - NoClassDefFoundError
我需要编译一个外部 java 文件(比如 a.java)。这是我为此编写的代码。 (字符串路径包含java和class文件的路径) command[0] = "javac"; comm
Java NoClassDefFoundError
我正在尝试运行一个基本的 Hibernate 程序。当我运行它时，出现以下错误 java.lang.NoClassDefFoundError: org/jboss/logging/BasicLogge
Eclipse插件开发无法实例化类由于java.lang.NoClassDefFoundError :
标题:Eclipse插件开发由于java.lang.NoClassDefFoundError无法实例化类: 试图构建一个 eclipse 插件，但遇到一些运行时错误.. 我知道这是由于代码所依赖的类文
喷雾 jar NoClassDefFoundError
我是新手，我无法让它工作......:/ 我的 build.sbt: val apacheDeps = Seq( "commons-validator" % "commons-validator"

塔克拉玛干

个人简介

我是一名优秀的程序员,十分优秀！

作者热门文章

滴滴打车优惠券免费领取

全站热门文章

首页

博学

6Ren·AI

商城

applet - Java 小程序 RuntimeException : java. lang.NoClassDefFoundError: javax/mail/Authenticator

更新1

来自

至

更新2

注意事项