精简版web浏览器

import javax.swing.JFrame;import javax.swing.JEditorPane;import javax.swing.event.HyperlinkListener;import java.beans.PropertyChangeListener;import javax.swing.event.HyperlinkEvent;import java.beans.PropertyChangeEvent;import javax.swing.JEditorPane;import javax.swing.JLabel;import javax.swing.JTextField;import javax.swing.JFileChooser;import javax.swing.JScrollPane;import java.awt.BorderLayout;import java.awt.event.WindowAdapter;import java.awt.event.WindowEvent;import javax.swing.JButton;import java.util.ArrayList;import java.net.MalformedURLException;import java.net.URL;import javax.swing.JMenu;import javax.swing.JMenuItem;import java.awt.event.ActionListener;import java.awt.event.ActionEvent;import javax.swing.filechooser.FileFilter;import java.io.File;import javax.swing.JOptionPane;import javax.swing.JMenuBar;import javax.swing.text.html.HTMLDocument;import javax.swing.JToolBar;import java.io.IOException;import java.awt.Dimension;import java.awt.Toolkit;import java.awt.event.KeyEvent;import java.util.Date;import java.text.SimpleDateFormat;/*【问题1】：点击"主页"按钮后，再次点击，下面文本提示一直在加载，没有返回结果，也没有返回超时【问题2】："打开"菜单功能未实现--is ok!【问题3】:页面链接的 输入类型(HyperlinkEvent.EventType.ENTERED)不起作用--可以支持http://www.baidu.com、http://www.hao123.com【问题4】：菜单中的快捷键如何使用？--先使用Alt+快捷键进入菜单，接着使用菜单项快捷键打开菜单项【问题5】：存放打开页面的队列满了是什么情况？*//**JFrame：顶级容器JPanel：普通容器JFrame的结构从里到外(按照图层的叠加顺序)依次为：frame->rootpane->layeredpane->contentpane->menuBar(optional)->glasspane ???frame ???????rootpane ???????????layeredpane ???????????????contentpane：默认是JPanel，一般的组件都放在JPanel ???????????????menuBar ???????????glasspane:默认是透明的 */public class WebBrowser extends JFrame implements HyperlinkListener,PropertyChangeListener{ ???/** ???JEditorPane的最主要功能在于展现不同类型的文件格式内容 ???第一种是纯文本类型，其类型的表示法为"text/plain",这种类型的文件就是我们最常使用的txt文件，这类型的文件可以用记事本或WordPad等文书编辑软件来编辑; ???第二种是RTF类型，其表示法为"text/rtf",这种类型的文件特色是能对文字内容做字体缩放、变形、上色等特殊效果; ???第三类是HTML类型，也就是我们在网络上所浏览的网页类型，其表示法为"text/html",这类文件的特色相信大家都非常的清楚，除了在对字体效果的表现之外还具有在文件 ???内加入图片、超级链接等相关功能。但是JEditorPane并不是一个全功能的Web Browser,它仅能支持简单的HTML语法.JEditorPane支持HTML类型的文件最主要的用途是用来制作在线辅助说明文件。 ???*/ ???????/*javax.swing组件*/ ???JEditorPane textPane; ???JLabel messageLable; ???????//contentPane的SOUTH ???JTextField urlField; ???????//URL单行输入框 ???JFileChooser fileChooser; ????//文件选择器 ???????/*前进和后退,在Button初始化要用到，在监听事件也要用到，所以作为成员变量*/ ???JButton backButton; ???JButton farwardButton; ???????java.util.List history = new ArrayList(); ???????//保存历史记录的列表 ???int currentHistoryPage = -1; ???????????????????????????????//当前页面在历史记录列表中的位置 ???//属于类仅有一个且为常量，类初始化时已经在内存中生成不可变，不管新建多少个浏览器对象实例，所有浏览器对象打开窗口的总数仅保留最新MAX_HISTORY条 ???public static final int MAX_HISTORY = 50; ???????//历史记录列表超出该值时，按顺序清除多余的历史记录 ???//属于类仅有一个，所有类对象实例共用同一个该静态变量 ???static int numBrowserWindows = 0; ???????????????????????//当前已经打开的浏览器窗口数 ???????//标识当所有浏览器窗口都关闭，是否退出程序 ???private static boolean exitWhenLastWindowClosed = false ; ???String home = "http://www.google.cn/"; ???????????//默认的主页 ???????//构造函数 ???public WebBrowser(){ ???????//super的调用必须是构造器中的第一个语句 ???????super("WebBrowser"); ???????//构造一个具有指定标题的，默认最初不可见的Frame对象 ???????textPane = new JEditorPane(); ???????//设置显示HTML的面板，并设置为不可编辑 ???????textPane.setEditable(false); ???????textPane.addHyperlinkListener(this); ???????????????????//注册事件处理器，用于超链接事件 ???????textPane.addPropertyChangeListener(this); ???????????//注册事件处理器，用于处理属性改变事件。当页面加载完成时，触发该事件 ???????????????this.getContentPane().add(new JScrollPane(textPane), BorderLayout.CENTER); ???????messageLable = new JLabel(); ???????this.getContentPane().add(messageLable, BorderLayout.SOUTH); ???????this.initMenu(); ???????this.initToolBar(); ???????//浏览器窗口加1 ???????//numBrowserWindows是属于类的，在创建WebBrowser对象实例前已经在内存中生成 ???????WebBrowser.numBrowserWindows++; ???????//当关闭窗口时，调用close方法处理(Y) ???????this.addWindowListener(new WindowAdapter(){ ???????????public void windowClosing(WindowEvent e){ ???????????????close(); ???????????????} ???????????}); ???????} ???????//初始化菜单栏，只允许子类继承和重写 ???????public ?void initMenu(){ ???????JMenu fileMenu = new JMenu("文件"); ???????//Alt+F ???????fileMenu.setMnemonic(‘F‘); ???????JMenuItem newMenuItem = new JMenuItem("新建"); ???????//先Alt+F，再N/Alt+N，快捷键有分层级，子菜单的快捷键不能直接使用 ???????newMenuItem.setMnemonic(‘N‘); ???????//匿名内部类继承一个父类或者实现一个接口，ActionListener为接口(Y) ???????newMenuItem.addActionListener(new ActionListener(){ ???????????//实现该接口的抽象方法 ???????????????public void actionPerformed(ActionEvent e){ ???????????????????newBrowser(); ???????????????????} ???????????}); ???????????????JMenuItem openMenuItem = new JMenuItem("打开"); ???????//先Alt+F，再O/Alt+O，快捷键有分层级，子菜单的快捷键不能直接使用// ???????openMenuItem.setMnemonic(‘O‘); ???????openMenuItem.setMnemonic(KeyEvent.VK_O); ???????//匿名内部类继承一个父类或者实现一个接口，ActionListener为接口(Y) ???????openMenuItem.addActionListener(new ActionListener(){ ???????????//实现该接口的抽象方法 ???????????????public void actionPerformed(ActionEvent e){ ???????????????????openLocalPage(); ???????????????????} ???????????}); ???????????????JMenuItem closeMenuItem = new JMenuItem("关闭"); ???????//先Alt+F，再C/Alt+C，快捷键有分层级，子菜单的快捷键不能直接使用 ???????closeMenuItem.setMnemonic(‘C‘); ???????//匿名内部类继承一个父类或者实现一个接口，ActionListener为接口(Y) ???????closeMenuItem.addActionListener(new ActionListener(){ ???????????//实现该接口的抽象方法 ???????????????public void actionPerformed(ActionEvent e){ ???????????????????close(); ???????????????????} ???????????}); ???????????????JMenuItem exitMenuItem = new JMenuItem("退出"); ???????//先Alt+F，再E/Alt+E，快捷键有分层级，子菜单的快捷键不能直接使用 ???????exitMenuItem.setMnemonic(‘E‘); ???????//匿名内部类继承一个父类或者实现一个接口，ActionListener为接口(Y) ???????exitMenuItem.addActionListener(new ActionListener(){ ???????????//实现该接口的抽象方法 ???????????????public void actionPerformed(ActionEvent e){ ???????????????????exit(); ???????????????????} ???????????}); ???????fileMenu.add(newMenuItem); ???????fileMenu.add(openMenuItem); ???????fileMenu.add(closeMenuItem); ???????fileMenu.add(exitMenuItem); ???????????????JMenu helpMenu = new JMenu("帮助"); ???????helpMenu.setMnemonic(‘H‘); ???????JMenuItem aboutMenuItem = new JMenuItem("关于"); ???????aboutMenuItem.setMnemonic(‘A‘); ???????????helpMenu.add(aboutMenuItem); ???????????????????JMenuBar menuBar = new JMenuBar(); ???????menuBar.add(fileMenu); ???????menuBar.add(helpMenu); ???????????????this.setJMenuBar(menuBar); ???????????????} ???????private void exit(){ ???????if(JOptionPane. ???showConfirmDialog(this, "你确定退出Web浏览器？", "退出", ????JOptionPane.YES_NO_OPTION)==JOptionPane.YES_OPTION){ ???????????System.exit(0); ???????????} ???????} ???????@SuppressWarnings("deprecation") ???private void openLocalPage(){ ???????if(fileChooser==null){ ???????????fileChooser = new JFileChooser(); ???????????//FileFilter为抽象类，使用内部类创建一个子类实例，实现FileFilter类的抽象方法(Y) ???????????FileFilter fileFilter = new FileFilter(){ ???????????????//File参数是文件过滤器对应类型的文件 ???????????????public ?boolean ???accept(File f){ ???????????????????String fileName = f.getName(); ???????????????????if((fileName.endsWith("html"))||(fileName.endsWith("htm"))){ ???????????????????????return true; ???????????????????????}else{return false;} ???????????????????} ???????????????public String ???getDescription(){ ???????????????????return "HTML Files"; ???????????????????} ???????????????}; ???????????//设置当前页面默认的文件筛选器 ???????????????fileChooser.setFileFilter(fileFilter); ???????????//当前页面的默认文件筛选器为系统默认的，仅表示把指定的文件筛选器添加到文件筛选器列表中 ???????????fileChooser.addChoosableFileFilter(fileFilter); ???????????} ???????//Pops up an "Open File" file chooser dialog,在"文件"选择器界面，如果点击"打开"按钮则返回0，如果点击"取消"或"X"按钮则返回1,其他异常返回-1 ???????int openResult = fileChooser.showOpenDialog(null); ???//返回值为0 ???????System.out.println("openResult: "+openResult); ???????if(openResult==JFileChooser.APPROVE_OPTION){ ???????????//仅支持选择单个文件，支持选择多个文件使用getSelectedFiles() ???????????File selectFile = fileChooser.getSelectedFile(); ???????????System.out.println(selectFile.toString()); ???????????try{ ???????????????//选择的本地文件向网页文件一样打开 ???????????????displayPage(selectFile.toURL()); ???????????}catch(MalformedURLException e){ ???????????????e.printStackTrace(); ???????????????} ???????????} ???????} ???public void setHome(String home){ ???????this.home = home; ???????} ???????????????public String getHome(){// ???????return this.home; ???????return home; ???????} ???????????//打开多个浏览器窗口，是否一个窗口最后一个页面关闭，所有窗口都会一并关闭？？ ???// ???public static void setExitWhenLastWindowClosed(boolean b){// ???????exitWhenLastWindowClosed = b;// ???????} ???????private void newBrowser(){ ???????//构造函数递归调用 ???????WebBrowser b = new WebBrowser(); ???????//this指外层构造函数生成的对象实例 ???????b.setSize(this.getWidth(),this.getHeight()); ???????b.setVisible(true); ???????} ???????????????//初始化工具栏，只允许子类继承和重写 ???protected void initToolBar(){ ???????backButton = new JButton("后退"); ???????backButton.setEnabled(true); ???????//匿名内部类为接口(Y) ???????backButton.addActionListener(new ActionListener(){ ???????????public void actionPerformed(ActionEvent e){ ???????????????back(); ???????????????} ???????????}); ???????????????????farwardButton = new JButton("前进"); ???????farwardButton.setEnabled(true); ???????//(Y) ???????farwardButton.addActionListener(new ActionListener(){ ???????????public void actionPerformed(ActionEvent e){ ???????????????forward(); ???????????????} ???????????}); ???????????????????JButton refresh = new JButton("刷新"); ???????refresh.setEnabled(true); ???????//(Y) ???????refresh.addActionListener(new ActionListener(){ ???????????public void actionPerformed(ActionEvent e){ ???????????????refresh(); ???????????????} ???????????}); ???????????????????JButton home = new JButton("主页"); ???????????home.setEnabled(true); ???????//(Y) ???????home.addActionListener(new ActionListener(){ ???????????public void actionPerformed(ActionEvent e){ ???????????????home(); ???????????????} ???????????}); ???????????????urlField = new JTextField(); ???????//(Y) ???????urlField.addActionListener(new ActionListener(){ ???????????public void actionPerformed(ActionEvent e){ ???????????????displayPage(urlField.getText()); ???????????????} ???????????}); ???????????????????JToolBar toolBar = new ????JToolBar(); ???????toolBar.add(backButton); ???????toolBar.add(farwardButton); ???????toolBar.add(refresh); ???????toolBar.add(home); ???????toolBar.add(new JLabel(" ??地址：")); ???????toolBar.add(urlField); ???????this.getContentPane().add(toolBar,BorderLayout.NORTH); ???????} ???????private void home(){ ???????displayPage(getHome()); ???????} ???????private void refresh(){ ???????if(currentHistoryPage != -1){ ???????????//先展示一个默认的HTMLDocument页面 ???????????textPane.setDocument(new HTMLDocument()); ???????????} ???????visit((URL)history.get(currentHistoryPage)); ???????} ???????????private void forward(){ ???????if(currentHistoryPage < (history.size()-1)){ ???????????visit((URL)history.get(++currentHistoryPage)); ???????????} ???????backButton.setEnabled((currentHistoryPage > 0)); ???????farwardButton.setEnabled((currentHistoryPage < (history.size()-1))); ???????} ???????????private void back(){ ???????if(currentHistoryPage > 0){ ???????????visit((URL)history.get(--currentHistoryPage)); ???????} ???????backButton.setEnabled((currentHistoryPage > 0)); ???????farwardButton.setEnabled((currentHistoryPage < (history.size()-1))); ???????} ???????????private boolean visit(URL url){ ???????try{ ???????????String href = url.toString(); ???????????startAnimation("加载" + href + "..."); ???????????textPane.setPage(href); ???????//Sets the current URL being displayed，加载完毕后触发addPropertyChangeListener事件 ???????????this.setTitle(href); ???????????urlField.setText(href); ???????????return true; ???????}catch(IOException e){ ???????????stopAnimation(); ???????????messageLable.setText("不能打开页面" + e.getMessage()); ???????????return false; ???????????} ???????} ???????@SuppressWarnings("unchecked") ???????private void displayPage(URL url){ ???????if(visit(url)){ ???????????this.history.add(url); ???????????int numentries = history.size(); ???????????System.out.println("numentries：" + numentries); ???????????for(int i=0;i<numentries;i++){ ???????????????System.out.println("history["+i+"] : " + history.get(i)); ???????????????} ???????????if(numentries > (MAX_HISTORY + 10)){ ???????????????history = history.subList((numentries - MAX_HISTORY), numentries); ???????????????currentHistoryPage = MAX_HISTORY; ???????????????} ???????????currentHistoryPage = ????(numentries - 1); ???????????//当前打开的页面会是最后一个吗？ ???????????if(currentHistoryPage > 0){ ???????????????backButton.setEnabled(true); ???????????????} ???????????} ???????} ???????????????public void displayPage(String href){ ???????try{ ???????????if(!href.startsWith("http://")){ ???????????href = "http://"+href; ???????????} ???????????displayPage(new URL(href)); ???????}catch(MalformedURLException e){ ???????????messageLable.setText("错误的网址：" + href); ???????????} ???????} ???????????public void close(){ ???????//隐藏当前窗口 ???????this.setVisible(false); ???????//销毁当前窗口的所有组件 ???????this.dispose(); ???????synchronized (WebBrowser.class){ ???????????//浏览器窗口减1 ???????????WebBrowser.numBrowserWindows--; ???????????//当Window监听器监听到关闭窗口事件，exitWhenLastWindowClosed标识默认为false，如果希望符合下面条件时关闭，则要提前通过setter设置 ???????????if((numBrowserWindows==0) && (exitWhenLastWindowClosed==true)){ ???????????????System.exit(0); ???????????????} ???????????} ???????} ???//动画消息，显示在最底下的状态栏标签上，用于反馈浏览器状态 ???????String animationMessage; ???//动画当前帧的索引 ???int ainimationFrame = 0; ???//动画用到的帧，是一些字符 ???String[] animationFrames = new String[]{"-", "\\", "|", "/", "-", "\\", "|", "/",",", ".", "o", "0", "O", "#", "*", "+"}; ???//新建一个Swing的定时器，每125ms更新一次状态栏标签的文本(Y) ???javax.swing.Timer animator = new javax.swing.Timer(125,new ActionListener(){ ???????public void actionPerformed(ActionEvent e){ ???????????animate(); ???????????} ???????}); ???//定时器启动后就一直不间断的执行任务 ???????private void animate(){ ???????String frame = animationFrames[ainimationFrame++]; ???????messageLable.setText(animationMessage + " "+ frame); ???????//循环遍历动画用到的所有帧 ???????ainimationFrame = ainimationFrame % animationFrames.length; ???????} ???????private void startAnimation(String message){ ???????animationMessage = message; ???????ainimationFrame = 0; ???????animator.start(); ???????} ???????????????private void stopAnimation(){ ???????System.out.println("信息标签停止播放动画!"); ???????animator.stop(); ???????messageLable.setText(" "); ???????} ???????????public static void setExitWhenLastWindowClosed(boolean exitWhenLastWindowClosed){ ???????WebBrowser.exitWhenLastWindowClosed = exitWhenLastWindowClosed; ???????} ???????????//实现HyperlinkListener接口的hyperlinkUpdate方法 ???public void hyperlinkUpdate(HyperlinkEvent e){ ???????System.out.println("HyperlinkEvent.getURL(): " + e.getURL()); ???????HyperlinkEvent.EventType type = e.getEventType();// ???????SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");//设置日期格式// ???????System.out.println(df.format(new Date())+" type: " + type); ???????//激活类型--光标点击超链接位置 ???????if(type==HyperlinkEvent.EventType.ACTIVATED){ ???????????displayPage(e.getURL()); ???????????} ???????//输入类型--光标放到超链接位置 ???????else if(type==HyperlinkEvent.EventType.ENTERED){ ???????????messageLable.setText(e.getURL().toString()); ???????????} ???????//退出的类型--光标移出超链接位置 ???????????else if(type==HyperlinkEvent.EventType.EXITED){ ???????????messageLable.setText(" "); ???????????} ???????????} ???????????//实现PropertyChangeListener接口的propertyChange方法 ???public void propertyChange(PropertyChangeEvent evt){ ???????System.out.println("PropertyName: "+evt.getPropertyName()); ???????//直到页面加载成功，之前都是对页面展示的准备，所有页面属性都是由JEditorPane完成，由PropertyChangeListener监听 ???????if(evt.getPropertyName().equals("page")){ ???????????stopAnimation(); ???????????} ???????} ???????????public static void main(String[] args){ ???????WebBrowser.setExitWhenLastWindowClosed(true); ???????WebBrowser browser = new WebBrowser(); ???????//获取屏幕分辨率，// ???????Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();// ???????browser.setSize(screenSize); ???????browser.setSize(800,700); ???????browser.setVisible(true); ???????browser.displayPage(browser.getHome()); ???????} ???????}