问题：
小程序无法在浏览器中工作
耿联
好吧，我知道有很多关于这个的问题和答案，但我真的没有任何运气。我有一个多类、多包程序，它也使用一些外部库（作为jar文件）。我也将我的项目导出为jar文件，下面是我的“index.html”，它引用了必要的库和我的jar文件。所有这些文件都放在同一个目录中，我可以在我的网页上看到小程序：http://easlnx01.eas.muohio.edu/~whitetc2/Twitter挖掘2/
<html>
<head>
<title>Java Example</title>
</head>
<body>
<center>
This is my page<br>
Below you see an applet<br>
<br>
<applet codebase ="." code="main.BasicGUI.class"
archive="twitter.jar, jsch-0-1.1.48.jar, twitter4j-core-2.2.5.jar, sftp.jar"
height="600" width="450"/>
</applet>
</center>
</body>
</html>
我的主类（BasicGUI.java）扩展了JApplet，并根据输入调用了各种其他类。它还具有public void init（）。谁能告诉我为什么这不完全有效？以下是我的网站的链接，该网站将在此处上载：http://easlnx01.eas.muohio.edu/~whitetc2/Twitter挖掘2/
如您所见，小程序出现了，但现在“文件”选项卡中的“选项”面板无法工作，程序本身也无法正常运行。
这是我的主要基本界面。java类：
package main;
import javax.swing.*;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.ListSelectionListener;
import javax.swing.JApplet;
import com.jscape.inet.sftp.SftpException;
import Twitter.SearchTweets;
import java.awt.*;
import java.awt.event.*;
import java.io.File;
import java.io.IOException;
import java.io.OutputStream;
import java.io.PrintStream;
/**
* The GUI for our Twitter Widget. Plans are to eventually
* set this up with a Java Applet to run straight from the
* CC teams website.
* @author Taylor White and Alex Meyer
*/
public class BasicGUI extends JApplet{
//Auto-generated
private static final long serialVersionUID = 1L;
//Aesthetic options, have getters and setters to allow for communication across GUIs
private static int opposite;
private static int maxTweets = 100;
private static boolean sortByLocation = false;
private static boolean isOptionsOpen = false;
// Options GUI, initiated here to avoid multiple open windows
//private OptionsGUI options;
// Initialize all swing objects.
private JPanel northSubPnl1;
private JPanel northSubPnl2;
private JPanel northSubPnl3;
private JPanel northPnl;
private JPanel eastPnl;
private JPanel westPnl;
private JLabel myQuery;
/** TWITTER INITILIAZATIONS **/
private static Twitter.TwitterDataList tweets;
/** END TWITTER INITIALIZATIONS **/
// Buttons
private JButton queryBtn; // Submits the query
private JButton uploadBtn;
// TextField Query
private JTextField txtQuery; // USER Query
// Menu
private JMenuBar mb; // Menu bar
private JMenu mnuFile; // File Entry on Menu bar
private JMenuItem mnuFileOpen;
private JMenuItem mnuFileSave;
private JMenuItem mnuFileOptions;
private JMenuItem mnuItemQuit; // Quit sub item
private JMenu mnuHelp; // Help Menu entry
private JMenuItem mnuItemAbout; // About Entry
//West Panel stuff
private static JList list;
private JScrollPane listScroller;
private JLabel uploadText;
private JCheckBox uploadHTML;
private JCheckBox uploadXML;
private JCheckBox uploadJSON;
//East Panel stuff
private JTextArea user;
private static JTextArea sysStatus;
private JScrollPane statusScroll;
private static JTextArea settings;
private static String keywords;
/*
* Getters and setters for aesthetic options
*/
public static boolean isSortedByLocation() {
return sortByLocation;
}
public static void setSortedByLocation(boolean toSort) {
sortByLocation = toSort;
}
public static int getMaxTweets() {
return maxTweets;
}
public static void setMaxTweets(int num) {
maxTweets = num;
}
public static boolean isOptionsOpen() {
return isOptionsOpen;
}
public static void setOptionsOpen(boolean option) {
isOptionsOpen = option;
}
/*
* CONSTRUCTOR
*/
public void init() {
sysStatus = new JTextArea (1, 20);
sysStatus.setEditable(false);
northSubPnl1 = new JPanel();
northSubPnl2 = new JPanel();
northSubPnl3 = new JPanel();
northPnl = new JPanel();
eastPnl = new JPanel();
westPnl = new JPanel();
myQuery = new JLabel ("You have no queries yet");
// TwitterDataList
tweets = new Twitter.TwitterDataList ();
// Buttons
queryBtn = new JButton("Submit Query"); // Submits the query
uploadBtn = new JButton("Upload Tweets"); // Uploads both XML and HTML files.
// TextField Query
txtQuery = new JTextField(); // USER Query
// Menu
mb = new JMenuBar(); // Menu bar
mnuFile = new JMenu("File");
mnuFileOpen = new JMenuItem("Open");
mnuFileSave = new JMenuItem("Save");
mnuFileOptions = new JMenuItem("Options");
mnuItemQuit = new JMenuItem("Quit");
mnuHelp = new JMenu("Help");
mnuItemAbout = new JMenuItem("About");
//West Panel stuff
String[] tweetsString = new String[2000];
list = new JList (tweetsString);
uploadText = new JLabel("Upload as:");
uploadHTML = new JCheckBox("HTML", false);
uploadXML = new JCheckBox("XML", false);
uploadJSON = new JCheckBox("JSON", false);
//East Panel stuff
user = new JTextArea("Username: ");
keywords = new String ();
statusScroll = new JScrollPane(sysStatus);
statusScroll.setPreferredSize(new Dimension(200, 150));
statusScroll.getVerticalScrollBar().setValue(statusScroll.getVerticalScrollBar().getMaximum());
settings = new JTextArea(1, 20);
// Set menu bar
this.setJMenuBar(mb);
//Build Menus
this.buildMenus();
// West Panel
this.westPnlSetup();
// East Panel
this.eastPnlSetup();
// Add objects to respective panels
this.northPnlSetup();
// Setup Main Frame
this.setLayout();
// Add Listeners
this.addListeners();
//Finish Launch
Toolkit toolkit = Toolkit.getDefaultToolkit ();
Dimension dim = toolkit.getScreenSize();
int width = (int)dim.getWidth();
int height = (int)dim.getHeight();; //worry about location later. This is fine for testing purposes
this.setBounds(width/2-400, height/2-400, 500, 800); //Arbitrarily chosen for a 1600 by 900 screen
this.setVisible(true);
}
public class ButtonListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
if (e.getSource() == queryBtn) {
if (txtQuery.getText().length() > 2) {
myQuery.setText("Your current query: " + txtQuery.getText());
tweets = Twitter.SearchTweets.customSearch(txtQuery.getText()); // SEARCH
if (SearchTweets.getKeywords() != null) {
if (tweets.getSize() > 0)
tweets = Twitter.SearchTweets.sortByKeyword(tweets, SearchTweets.getKeywords()); // Sort right after.
else {
print("No tweets found!");
System.out.println("No tweets found!");
}
}
if (tweets.getSize() > 0) {
list.setListData(tweets.toArray(maxTweets));
sysStatus.append("Top Tweet: " + tweets.get(0).getTweet());
System.out.println("Top Tweet: " + tweets.get(0).getTweet());
//tweets.saveHTML(txtQuery.getText()); NOT SAVING BY DEFAULT ANY MORE
}
else {
print("No tweets found!");
System.out.println("No tweets found!");
}
}
else {
print("Please input at least a 3 letter word to begin a query.");
System.out.println("Please input at least a 3 letter word to begin a query.");
}
}
// Not sure how to make directory path independent of system. change path to your local project to get open and save to work
else if (e.getSource() == mnuFileOpen) {
final JFileChooser fc = new JFileChooser("C:/Users/Meyer/Desktop/YATE/DataCollection");
int returnVal = fc.showOpenDialog(mnuFile);
if (returnVal == JFileChooser.APPROVE_OPTION) {
File file = fc.getSelectedFile();
tweets = Twitter.TwitterDataList.load(file.getName());
if (SearchTweets.getKeywords() != null) {
tweets = Twitter.SearchTweets.sortByKeyword(tweets, SearchTweets.getKeywords());
}
list.setListData(tweets.toArray(maxTweets));
myQuery.setText("Your current query: " + file.getName());
}
}
else if (e.getSource() == mnuFileSave) {
final JFileChooser fc = new JFileChooser("C:/Users/Meyer/Desktop/YATE/DataCollection");
int returnVal = fc.showSaveDialog(mnuFile);
if (returnVal == JFileChooser.APPROVE_OPTION) {
File file = fc.getSelectedFile();
tweets.writeHTML(file.getName());
}
}
else if (e.getSource() == mnuFileOptions) {
if (!isOptionsOpen()) {
new OptionsGUI();
setOptionsOpen(true);
}
}
else if (e.getSource() == uploadBtn) {
if (uploadHTML.isSelected() ||
uploadXML.isSelected() || uploadJSON.isSelected()) {
try {
tweets.saveAll(txtQuery.getText(), uploadHTML.isSelected(),
uploadXML.isSelected(), uploadJSON.isSelected());
} catch (SftpException exception) {
System.out.println("Could not upload. Try another time.");
print("Could not upload. Try another time.");
}
}
else if (tweets.getSize() ==0) {
JOptionPane.showMessageDialog(null, "There are no tweets to upload!");
}
else {
JOptionPane.showMessageDialog(null, "You need to select a file type in order to upload.");
}
}
}
}
public class KeyChecker implements KeyListener {
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_ENTER)
queryBtn.doClick();
}
public void keyReleased(KeyEvent arg0) {
//ignore
}
public void keyTyped(KeyEvent arg0) {
//ignore
}
}
public class ListListener implements ListSelectionListener {
public void valueChanged(ListSelectionEvent e) {
try {
user.setText(tweets.get(list.getSelectedIndex()).toString());
} catch (ArrayIndexOutOfBoundsException error) {
user.setText(tweets.get(list.getFirstVisibleIndex()).toString());
}
}
}
public class ListenMenuQuit implements ActionListener{
public void actionPerformed(ActionEvent e){
System.exit(0);
}
}
public class ListenCloseWdw extends WindowAdapter{
public void windowClosing(WindowEvent e){
System.exit(0);
}
}
public void buildMenus () {
mnuFile.add(mnuFileOpen);
mnuFile.add(mnuFileSave);
mnuFile.add(mnuFileOptions);
mnuFile.add(mnuItemQuit); // Create Quit line
mnuHelp.add(mnuItemAbout); // Create About line
mb.add(mnuFile); // Add Menu items to form
mb.add(mnuHelp);
}
/**
* North Panel
*/
public void northPnlSetup () {
northPnl.setLayout(new BoxLayout (northPnl, BoxLayout.Y_AXIS));
northSubPnl1.add(txtQuery);
northSubPnl1.add(queryBtn);
txtQuery.setColumns(20);
northPnl.add(northSubPnl1);
}
/**
* Sets Layout of GUI
*/
public void setLayout () {
// Setup Main Frame
this.getContentPane().setLayout(new BorderLayout());
this.getContentPane().add(northPnl, BorderLayout.NORTH);
this.getContentPane().add(westPnl, BorderLayout.WEST);
this.getContentPane().add(eastPnl, BorderLayout.EAST);
}
/*
* Adds action listeners
*/
public void addListeners(){
mnuItemQuit.addActionListener(new ListenMenuQuit());
mnuFileOpen.addActionListener(new ButtonListener());
mnuFileSave.addActionListener(new ButtonListener());
mnuFileOptions.addActionListener(new ButtonListener());
queryBtn.addActionListener(new ButtonListener());
uploadBtn.addActionListener(new ButtonListener());
list.addListSelectionListener(new ListListener());
txtQuery.addKeyListener(new KeyChecker());
}
public void westPnlSetup () {
westPnl.add(new JLabel ("Tweets"));
westPnl.add(new JLabel("-------"));
westPnl.setLayout(new BoxLayout (westPnl, BoxLayout.Y_AXIS));
listScroller = new JScrollPane(list);
listScroller.setPreferredSize(new Dimension(200, 100));
list.setListData(tweets.toArray(maxTweets));
list.setSelectionMode(ListSelectionModel.SINGLE_INTERVAL_SELECTION);
list.setLayoutOrientation(JList.VERTICAL);
list.setVisibleRowCount(10);
westPnl.add(listScroller);
// setup upload button and panel for check boxes
northSubPnl2.setLayout(new BoxLayout(northSubPnl2, BoxLayout.Y_AXIS));
northSubPnl2.add(uploadBtn);
uploadBtn.setAlignmentX(CENTER_ALIGNMENT);
northSubPnl2.add(uploadText);
uploadText.setAlignmentX(CENTER_ALIGNMENT);
northSubPnl2.add(northSubPnl3);
// setup check boxes
northSubPnl3.setLayout(new BoxLayout(northSubPnl3, BoxLayout.X_AXIS));
northSubPnl3.add(uploadHTML);
northSubPnl3.add(uploadXML);
northSubPnl3.add(uploadJSON);
westPnl.add(northSubPnl2);
}
public void eastPnlSetup () {
eastPnl.setLayout(new BoxLayout (eastPnl, BoxLayout.Y_AXIS));
eastPnl.add(new JLabel("Metadata"));
eastPnl.add(new JLabel("-------"));
user = new JTextArea(1, 20);
user.setPreferredSize(new Dimension (200,50));
user.setEditable(false);
user.append("User: \n");
user.append("Date: \n");
user.append("Location: \n");
user.append("Relevance: \n");
user.append("Tweet: ");
user.setWrapStyleWord(true);
user.setLineWrap(true);
eastPnl.add(user);
eastPnl.add(new JLabel("Settings"));
eastPnl.add(new JLabel(new JLabel("-------").getText()));
String keywords = "";
for (int i = 0; i < SearchTweets.getKeywords().size(); i++) {
keywords = SearchTweets.getKeywords().get(i) + ", ";
}
try {
keywords = keywords.substring(0, keywords.length()-2);
} catch (StringIndexOutOfBoundsException e) {
keywords = ""; // There are no keywords if this happens.
}
/*
* || THIS IS IF IN WHITE ||
* || ||
* VV VV
*/
settings.setPreferredSize(new Dimension (200,50));
settings.setEditable(false);
BasicGUI.setSettingsPaneValues();
settings.setWrapStyleWord(true);
settings.setLineWrap(true);
eastPnl.add(settings);
sysStatus.append(">");
eastPnl.add(new JLabel("System Status "));
eastPnl.add(new JLabel(new JLabel("-------").getText()+"----"));
sysStatus.setWrapStyleWord(true);
sysStatus.setLineWrap(true);
eastPnl.add(statusScroll);
//this.redirectSystemStreams(); // REDIRECTS the text of console to the sysStatus box. NOT REAL TIME.
/* END WHITE */
}
public static void setSettingsPaneValues () {
keywords = new String();
for (int i = 0; i < SearchTweets.getKeywords().size(); i++) {
keywords += SearchTweets.getKeywords().get(i) + ", ";
}
if (SearchTweets.getKeywords().size()== 0) {
keywords = "none";
}
else {
try {
keywords = keywords.substring(0, keywords.length()-2);
} catch (StringIndexOutOfBoundsException e) {
keywords = ""; // There are no keywords if this happens.
}
}
settings.setText("Sort by location: " + isSortedByLocation() +
"\nTimeout (in seconds): " + SearchTweets.getTimeout() +
"\nMaximum tweets shown: " + getMaxTweets() +
"\nKeywords: " + keywords);
if (SearchTweets.getKeywords() != null && tweets.getSize() > 0) {
tweets = Twitter.SearchTweets.sortByKeyword(tweets, SearchTweets.getKeywords());
}
list.setListData(tweets.toArray(maxTweets));
list.repaint();
}
/**
* returns string value of the keywords used
* @return returns instance variable keywords
* @author Taylor
*/
public static String getKeywords () {
return keywords;
}
/**
* Updates the sysStatus textArea
* @param text
*/
private void updateTextArea(final String text) {
SwingUtilities.invokeLater(new Runnable() {
public void run() {
opposite++;
opposite = opposite%2;
if (!text.equalsIgnoreCase(".")){ // So I can do the ". . ." sequence to signify waiting.
if (opposite%2 == 1) {
sysStatus.append("\n>" + text);
}
else sysStatus.append(text);
}
else sysStatus.append(text);
}
});
}
/**
* Allows other classes to print to sysStatus
*/
public static void print (String text) {
opposite++;
opposite = opposite%2;
if (!text.equalsIgnoreCase(".")){ // So I can do the ". . ." sequence to signify waiting.
//if (opposite%2 == 1) {
sysStatus.append("\n\n>" + text);
sysStatus.repaint();
//}
//else sysStatus.append("\n" + text);
}
else sysStatus.append(text);
sysStatus.invalidate();
sysStatus.repaint();
}
/**
* Redirects all console output to the textarea.
*/
@SuppressWarnings("unused")
private void redirectSystemStreams() {
OutputStream out = new OutputStream() {
@Override
public void write(int b) throws IOException {
updateTextArea(String.valueOf((char) b));
}
@Override
public void write(byte[] b, int off, int len) throws IOException {
updateTextArea(new String(b, off, len));
}
@Override
public void write(byte[] b) throws IOException {
write(b, 0, b.length);
}
};
System.setOut(new PrintStream(out, true));
System.setErr(new PrintStream(out, true));
}
}
共有1个答案
钱卓君
从此处开始：
Exception in thread "AWT-EventQueue-2" java.lang.AssertionError: java.lang.reflect.InvocationTargetException
at twitter4j.TwitterFactory.<clinit>(TwitterFactory.java:76)
...
Caused by: java.lang.reflect.InvocationTargetException
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
... 42 more
Caused by: java.lang.ExceptionInInitializerError
at twitter4j.internal.http.HttpClientWrapper.<init>(HttpClientWrapper.java:48)
... 47 more
Caused by: java.security.AccessControlException: access denied
(java.util.PropertyPermission twitter4j.http.httpClient read)
at java.security.AccessControlContext.checkPermission(Unknown Source)
at java.security.AccessController.checkPermission(Unknown Source)
通常，小程序在限制性安全沙盒中运行。要获取所有属性或跨站点访问，小程序需要由您进行数字签名，并得到最终用户的信任（他们“在提示时单击确定”）。
一般提示：
- 将Java控制台配置为在加载小程序时弹出。你现在是“盲目飞行”
- 对于损坏的代码，请确保每个catch调用都可以丢弃。printStackTrace（）
类似资料：
-
我试图运行一些单元测试使用Selenium网络驱动程序和C#。NET for Firefox浏览器，但我无法做到这一点（Chrome和IE11浏览器工作顺利）。 以下是我收集的信息： 操作系统：Windows 10企业版 Gecko驱动程序版本：geckodriver-v0。17.0-win32 Mozilla Firefox版本：54.0.1（32位） 已在“C:\LEO\SELENIUM C\
-
问题内容： 我只是从Java小程序开始，然后发现了这个提供教程的网站。我输入了所有代码，但该小程序未显示在我的浏览器中：HelloWorld.java 这是我的HTML文件 我已经编译了Java文件（HelloWorld.class），并将所有文件保存在桌面上。我在Mac OS X美洲狮上使用的是野生动物园的最新版本。我在谷歌浏览器中尝试过，并说要安装一个插件，但是我没有做任何事情？ 问题答案：
-
我正在尝试dockerise一个反应应用程序。我正在使用以下Dockerfile来实现这一点。 还有，在我的包裹里。json开始脚本被定义为
-
我正在使用WebDriver（Eclipse-Java）来自动化注册页面。点击“注册”按钮时，会显示一条“成功消息”，并需要验证该消息。 我可以在IE8中成功地做到这一点。但无法在Firefox中验证相同的内容。我试过不同的等待。D1.manage().timeouts().implicitlywait(60，TimeUnit.seconds)； > WebDriverWait wait=新建We
-
问题内容： 我正在尝试在我的网站上部署Java applet。我还需要签名，因为我需要访问剪贴板。我遵循了所有可以找到但没有成功的签名教程。到目前为止，这是我所做的： 在NetBeans中编写了一个applet。它在applet查看器中运行良好。 从中制作一个.jar文件。 通过执行以下操作创建证书： 像这样用jarsigner签名： 制作了一个包含以下内容的html文件： 当我打开该html文件