*网页浏览器主程序

[color=#FF00FF]java 初学者，请教如何用eclipse实现如下程序
[color=#FF0000]
**网页浏览器主程序
**WebBrowser.java
*/
[color=#000000]import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.net.URL;
import java.util.ArrayList;
import javax.swing.*;
import javax.swing.event.*;[/color][/color]@SuppressWarnings("serial")
public class WebBrowser extends JFrame implements HyperlinkListener,ActionListener[/color]{ 
 //这些都是什么啊，怎么实现啊
    //建立工具栏用来显示地址栏
    JToolBar bar=new JToolBar ();
   
    //建立网页显示界面
    JTextField jurl = new JTextField (60);
    JEditorPane jEditorPane1 = new JEditorPane ();
    JScrollPane scrollPane = new JScrollPane (jEditorPane1);
   
    JFileChooser chooser=new JFileChooser ();
    JFileChooser chooser1=new JFileChooser ();
    String htmlSource;
    JWindow window = new JWindow (WebBrowser.this);
    JButton button2=new JButton ("窗口还原");
    Toolkit toolkit = Toolkit.getDefaultToolkit();
   
    //建立菜单栏
    JMenuBar jMenuBar1 = new JMenuBar();
    //建立菜单组
    JMenu fileMenu = new JMenu ("文件(F)");
    //建立菜单项
    JMenuItem saveAsItem = new JMenuItem ("另存为(A)...");
    JMenuItem exitItem=new JMenuItem ("退出(I)");
   
    JMenu editMenu=new JMenu ("编辑(E)");
    JMenuItem backItem=new JMenuItem ("后退");
    JMenuItem forwardItem=new JMenuItem ("前进");
   
    JMenu viewMenu=new JMenu ("视图(V)");
    JMenuItem fullscreenItem=new JMenuItem ("全屏(U)");
    JMenuItem sourceItem=new JMenuItem ("查看源码(C)");
    JMenuItem reloadItem=new JMenuItem ("刷新(R)");

    //建立工具栏
    JToolBar toolBar = new JToolBar();
    //建立工具栏中的按钮组件
    JButton picSave = new JButton("另存为");
    JButton picBack = new JButton("后退");
    JButton picForward = new JButton("前进");
    JButton picView = new JButton("查看源代码");
    JButton picExit = new JButton("退出");

    JLabel label=new JLabel ("地址");
    JButton button=new JButton ("转向");
   
    Box adress=Box.createHorizontalBox ();   

    //ArrayList对象，用来存放历史地址
    @SuppressWarnings("rawtypes")
 private ArrayList history=new ArrayList();
    //整型变量，表示历史地址的访问顺序
    private int historyIndex;

    /**
    **构造函数
    **初始化图形用户界面
    */
    public WebBrowser(){
       
        setTitle ("web浏览器 11软件技术302班");
        setResizable(false);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                   
        //为jEditorPane1添加事件侦听
        jEditorPane1.addHyperlinkListener (this);
       
        //为组件fileMenu设置热键‘F’
        fileMenu.setMnemonic('F');
       
        saveAsItem.setMnemonic ('S');
        //为“另存为”组件设置快捷键为ctrl+s
        saveAsItem.setAccelerator (KeyStroke.getKeyStroke (KeyEvent.VK_S,InputEvent.CTRL_MASK));
       
        exitItem.setMnemonic('Q');
        exitItem.setAccelerator (KeyStroke.getKeyStroke (KeyEvent.VK_E,InputEvent.CTRL_MASK));
       
        //将菜单项saveAsItem加入到菜单组fileMenu中
        fileMenu.add (saveAsItem);
        //在菜单项中添加隔离
        fileMenu.addSeparator ();
        fileMenu.add (exitItem);
       
        backItem.setMnemonic ('B');
        backItem.setAccelerator (KeyStroke.getKeyStroke (KeyEvent.VK_Z,InputEvent.CTRL_MASK));
        forwardItem.setMnemonic('D');
        forwardItem.setAccelerator (KeyStroke.getKeyStroke (KeyEvent.VK_P,InputEvent.CTRL_MASK));
       
        editMenu.setMnemonic('E');
        editMenu.add (backItem);
        editMenu.add (forwardItem); 
       
        viewMenu.setMnemonic('V');
       
        fullscreenItem.setMnemonic('U');
        fullscreenItem.setAccelerator (KeyStroke.getKeyStroke (KeyEvent.VK_U,InputEvent.CTRL_MASK));
        sourceItem.setMnemonic('C');
        sourceItem.setAccelerator (KeyStroke.getKeyStroke (KeyEvent.VK_C,InputEvent.CTRL_MASK));
        reloadItem.setMnemonic('R');
        reloadItem.setAccelerator (KeyStroke.getKeyStroke (KeyEvent.VK_R,InputEvent.CTRL_MASK));
       
        Container contentPane=getContentPane ();
           
        //设置大小
        scrollPane.setPreferredSize(new Dimension(100,500));
        contentPane.add (scrollPane, BorderLayout.SOUTH);
       
        //在工具栏中添加按钮组件
        toolBar.add(picSave);
        toolBar.addSeparator();
        toolBar.add(picBack);
        toolBar.add(picForward);
        toolBar.addSeparator();
        toolBar.add(picView);
        toolBar.addSeparator();
        toolBar.add(picExit);
       
        contentPane.add (bar,BorderLayout.CENTER);
        contentPane.add(toolBar,BorderLayout.NORTH);
       
        viewMenu.add (fullscreenItem);
        viewMenu.add (sourceItem);
        viewMenu.addSeparator ();
        viewMenu.add (reloadItem);
       
        jMenuBar1.add (fileMenu);
        jMenuBar1.add (editMenu);
        jMenuBar1.add (viewMenu);

        setJMenuBar (jMenuBar1);
   
        adress.add (label);
        adress.add (jurl);
        adress.add (button);
        bar.add (adress);
       
        //为组件添加事件监听
        saveAsItem.addActionListener(this);
        picSave.addActionListener(this);
        exitItem.addActionListener(this);
        picExit.addActionListener(this);
        backItem.addActionListener(this);
        picBack.addActionListener(this);
        forwardItem.addActionListener(this);
        picForward.addActionListener(this);
        fullscreenItem.addActionListener(this);
        sourceItem.addActionListener(this);
        picView.addActionListener(this);
        reloadItem.addActionListener(this);
        button.addActionListener(this);
        jurl.addActionListener(this);
    }
   
    /**
    **实现监听器接口的actionPerformed函数
    */
    @SuppressWarnings("unchecked")
 public void actionPerformed(ActionEvent e) {
        String url = "";
        //点击转向按钮
        if (e.getSource() == button){
            //获得地址栏的内容
            url=jurl.getText ();
            //url不为“”，并且以“http://”开头
            if(url.length ()>0&&url.startsWith ("http://")){
                try {
                    //JEditorPane组件显示url的内容链接
                    jEditorPane1.setPage (url);
                    //将url的内容添加到ArrayList对象history中
                    history.add(url);
                    //historyIndex的数值设为history对象的长度-1
                    historyIndex=history.size()-1;
                    //重新布局
      jEditorPane1.setEditable(false); //add by copy editor :)
                    jEditorPane1.revalidate ();
                }
                catch(Exception ex) {
                    //如果链接显示失败，则弹出选择对话框“无法打开该搜索页”
                    JOptionPane.showMessageDialog (WebBrowser.this,"无法打开该搜索页","网页浏览器",JOptionPane.ERROR_MESSAGE);
                }
            }
            //url不为“”，并且不以“http://”开头
            else if(url.length ()>0&&!url.startsWith ("http://")) {
                //在url前面添加“http://”
                url="http://"+url;
                try {
                    jEditorPane1.setPage (url );
                    history.add(url);
                    historyIndex=history.size()-1;
      jEditorPane1.setEditable(false); //add by copy editor :)
                    jEditorPane1.revalidate ();
                }
                catch(Exception ex) {
                    JOptionPane.showMessageDialog (WebBrowser.this,"无法打开该搜索页","网页浏览器",JOptionPane.ERROR_MESSAGE);
                }
            }
            //没有输入url，即url为空
            else if(url.length ()==0){
                JOptionPane.showMessageDialog (WebBrowser.this,"请输入链接地址","网页浏览器",JOptionPane.ERROR_MESSAGE);
            }
       
        }
        //输入地址后点击回车
        else if (e.getSource() == jurl){
            url=jurl.getText ();
            if(url.length ()>0&&url.startsWith ("http://")) {
                try {
                    jEditorPane1.setPage (url);
                    history.add(url);
                    historyIndex=history.size()-1;
      jEditorPane1.setEditable(false); //add by copy editor :)
                    jEditorPane1.revalidate ();
                    jurl.setMaximumSize (jurl.getPreferredSize ());
                }
                catch(Exception ex) {
                    JOptionPane.showMessageDialog (WebBrowser.this,"无法打开该搜索页","网页浏览器",JOptionPane.ERROR_MESSAGE);
                }
            }
            else if(url.length ()>0&&!url.startsWith ("http://")) {
                url="http://"+url;
                try {
                    jEditorPane1.setPage (url );
                    history.add(url);
                    historyIndex=history.size()-1;
      jEditorPane1.setEditable(false); //add by copy editor :)
                    jEditorPane1.revalidate ();
                }
                catch(Exception ex) {
                    JOptionPane.showMessageDialog (WebBrowser.this,"无法打开该搜索页","网页浏览器",JOptionPane.ERROR_MESSAGE);
                }
            }
            else if(url.length ()==0){
                JOptionPane.showMessageDialog (WebBrowser.this,"请输入链接地址","网页浏览器",JOptionPane.ERROR_MESSAGE);
            }
        }
        //另存为...
        else if (e.getSource() == picSave||e.getSource() == saveAsItem){
            url = jurl.getText ().toString ().trim();
            if(url.length ()>0&&!url.startsWith ("http://")) {
                url="http://"+url;
            }
            if(!url.equals ("")) {
                //保存文件
                saveFile(url);
            }
            else {
                JOptionPane.showMessageDialog (WebBrowser.this,"请输入链接地址","网页浏览器",JOptionPane.ERROR_MESSAGE);
            }
        }
        //退出
        else if (e.getSource() == exitItem ||e.getSource() == picExit){
            System.exit(0);
        }
        //后退
        else if (e.getSource() == backItem ||e.getSource() == picBack){
            historyIndex--;
            if(historyIndex < 0)
                historyIndex = 0;
            url = jurl.getText();
            try{
                //获得history对象中本地址之前访问的地址
                url = (String)history.get(historyIndex);
                jEditorPane1.setPage(url);
                jurl.setText(url.toString());
  jEditorPane1.setEditable(false); //add by copy editor :)
                jEditorPane1.revalidate ();
            }
            catch(Exception ex){
            }
        }
        //前进
        else if (e.getSource() == forwardItem ||e.getSource() == picForward){
            historyIndex++;
            if(historyIndex >= history.size())
                    historyIndex = history.size()-1;
            url = jurl.getText();
            try{
                //获得history对象中本地址之后访问的地址
                url = (String)history.get(historyIndex);
                jEditorPane1.setPage(url);
                jurl.setText(url.toString());
  jEditorPane1.setEditable(false); //add by copy editor :)
                jEditorPane1.revalidate ();
            }
            catch(Exception ex){
            }
        }
        //全屏
        else if (e.getSource() == fullscreenItem){
            boolean add_button2=true;
            //获得屏幕大小
            Dimension size = Toolkit.getDefaultToolkit().getScreenSize();

            Container content = window.getContentPane();
            content.add (bar,"North");
            content.add (scrollPane,"Center");
               
            //button2为点击“全屏”后的还原按钮
            if(add_button2==true) {
                bar.add (button2);
            }
            //为button2添加事件
            button2.addActionListener (new ActionListener () {
                public void actionPerformed (ActionEvent evt) {
                    WebBrowser.this.setEnabled (true);
                    window.remove (bar);
                    window.remove (toolBar);
                    window.remove (scrollPane);
                    window.setVisible (false);
                   
                    scrollPane.setPreferredSize (new Dimension (100,500));
                    getContentPane ().add (scrollPane,BorderLayout.SOUTH);
                    getContentPane ().add (bar,BorderLayout.CENTER);
                    getContentPane ().add (toolBar,BorderLayout.NORTH);
                    bar.remove (button2);
                    pack();
                }
            });
            window.setSize (size);
            window.setVisible (true);
        }
        //查看源文件
        else if (e.getSource() == sourceItem ||e.getSource() == picView){
            url = jurl.getText ().toString ().trim ();
                if(url.length ()>0&&!url.startsWith ("http://")) {
                    url="http://"+url;
                }
                if( !url.equals ("")) {
                    //根据url，获得源代码
                    getHtmlSource (url);
                    //生成显示源代码的框架对象
                    ViewSourceFrame vsframe = new ViewSourceFrame (htmlSource);
                    vsframe.setBounds (0,0,800,500);
                    vsframe.setVisible(true);
                }
                else {
                    JOptionPane.showMessageDialog (WebBrowser.this,"请输入链接地址","网页浏览器",JOptionPane.ERROR_MESSAGE);
                }
        }
        //刷新
        else if (e.getSource() == reloadItem){
            url=jurl.getText ();
            if(url.length ()>0&&url.startsWith ("http://")) {
                try {
                    jEditorPane1.setPage (url);
      jEditorPane1.setEditable(false); //add by copy editor :)
                    jEditorPane1.revalidate ();
                }
                catch(Exception ex) {
                }
            }
            else if(url.length ()>0&&!url.startsWith ("http://")) {
                url="http://"+url;
                try {
                    jEditorPane1.setPage (url );
      jEditorPane1.setEditable(false); //add by copy editor :)
                    jEditorPane1.revalidate ();
                }
                catch(Exception ex) {
                }
            }
        }
    }
   
    /*
    **保存文件
    */
    void saveFile (final String url) {
        final String linesep = System.getProperty ("line.separator");
        chooser1.setCurrentDirectory (new File ("."));
        chooser1.setDialogType (JFileChooser.SAVE_DIALOG);
        chooser1.setDialogTitle ("另存为...");
        if(chooser1.showSaveDialog (this) != JFileChooser.APPROVE_OPTION)
            return;
        this.repaint ();
        Thread thread = new Thread () {
            public void run () {
                try {
                    java.net.URL source = new URL (url);
                    InputStream in = new BufferedInputStream (source.openStream ());
                    BufferedReader br=new BufferedReader (new InputStreamReader (in));
                    File fileName = chooser1.getSelectedFile ();
                    FileWriter out = new FileWriter (fileName);
                    BufferedWriter bw = new BufferedWriter (out);
                    String line;
                    while((line = br.readLine ()) != null) {
                        bw.write (line);
                        bw.newLine ();
                    }
                    bw.flush ();
                    bw.close ();
                    out.close ();
                    String dMessage = url + " 已经被保存至"+ linesep +fileName.getAbsolutePath ();
                    String dTitle = "另存为";
                    int dType = JOptionPane.INFORMATION_MESSAGE;
                    JOptionPane.showMessageDialog ((Component) null,dMessage,dTitle,dType);
                }
                catch(java.net.MalformedURLException muex) {
                    JOptionPane.showMessageDialog ((Component)null,muex.toString (),"网页浏览器",JOptionPane.ERROR_MESSAGE);
                }
                catch(Exception ex) {
                    JOptionPane.showMessageDialog ((Component) null,ex.toString (),"网页浏览器",JOptionPane.ERROR_MESSAGE);
                }
            }
        };
        thread.start ();
    }

    /*
    **获得源代码
    */
    void getHtmlSource (String url) {
        String linesep,htmlLine;
        linesep = System.getProperty ("line.separator");
        htmlSource ="";
        try {
            java.net.URL source = new URL (url);
            InputStream in = new BufferedInputStream (source.openStream ());
            BufferedReader br = new BufferedReader ( new InputStreamReader (in));
            while((htmlLine = br.readLine ())!=null) {
                htmlSource = htmlSource +htmlLine+linesep;
            }
        }
        catch(java.net.MalformedURLException muex) {
            JOptionPane.showMessageDialog (WebBrowser.this,muex.toString (),"网页浏览器",JOptionPane.ERROR_MESSAGE);
        }
        catch(Exception e) {
            JOptionPane.showMessageDialog (WebBrowser.this,e.toString (),"网页浏览器",JOptionPane.ERROR_MESSAGE);
        }
    }
   
    /**
    **实现监听器接口的hyperlinkUpdate函数
    */
    public void hyperlinkUpdate (HyperlinkEvent e) {
    /*    if(e.getEventType () == HyperlinkEvent.EventType.ACTIVATED) {
            String url = jurl.getText();
            if(url.length ()>0&&url.startsWith ("http://")) {
                try {
                    jEditorPane1.setPage (url);
                    jEditorPane1.revalidate ();
                }
                catch(Exception ex) {
                }
            }
            else if(url.length ()>0&&!url.startsWith ("http://")) {
                url="http://"+url;
                try {
                    jEditorPane1.setPage (url );
                    jEditorPane1.revalidate ();
                }
                catch(Exception ex) {
                }
            }
        }
    */
    // Revised by copy editor :) Now with new code to help hyperlink
 try {
   if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED)
    jEditorPane1.setPage(e.getURL());
   } catch (Exception ex) {
    ex.printStackTrace(System.err);
   }
    }
   
    /*生成一个IE对象*/
    public static void main (String [] args){
        try{
            UIManager.setLookAndFeel(
                UIManager.getCrossPlatformLookAndFeelClassName()
            );
        }
        catch(Exception e){
        }

        WebBrowser webBrowser = new WebBrowser ();
        webBrowser.pack();
        webBrowser.setVisible(true);
    }
}