java网页浏览器设计
/*
**网页浏览器主程序
**WebBrowser.java
*/
import java.awt.*; 
import javax.swing.*;
import javax.swing.text.*;
import java.awt.event.*; 
import javax.swing.event.*;
import javax.swing.border.*;
import javax.swing.filechooser.FileFilter; 
import javax.swing.filechooser.FileView; 
import java.io.*; 
import java.net.*; 
import java.util.*; 
public class WebBrowser extends JFrame implements HyperlinkListener,ActionListener{
    //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
    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 ("网页浏览器"); 
        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X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X听*X器接口的actionPerformed函数
    */
    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://www.751com.cn"+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);
        }140