基于java的网页浏览器_JAVA_编程开发_程序员俱乐部

用java编写简单网页浏览器，用到两个类WebBrowser and ViewSourceFreme，他们分别的功能是：

WebBrowser.java 类是网页浏览器的主类文件，生成网页浏览器的主题框架，并实现框架上各个组件的监听事件。ViewSourceFrame.java类是实现网页浏览器源代码查看的主体框架，并提供了源代码的保存功能。

好了，废话少说，直接上代码

package Browser;

import java.awt.*;

import javax.swing.event.*;

import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.InputEvent;
import java.awt.event.KeyEvent;
import java.io.*;
import java.util.ArrayList;
import java.net.*;

import javax.swing.*;
import javax.swing.event.HyperlinkEvent;
import javax.swing.event.HyperlinkListener;
import javax.swing.text.*;

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("还原窗口");
?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(X)");
?
?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("源代码(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
?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添加时间侦听
??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Ctrl+S
??saveAsItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_S,InputEvent.CTRL_MASK));
??exitItem.setMnemonic('X');
??exitItem.setAccelerator(KeyStroke.getKeyStroke(KeyEvent.VK_E,InputEvent.CTRL_MASK));
??//将菜单项saveAsItem加入菜单组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);
??adress.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
? */

?public void actionPerformed(ActionEvent e) {
??// TODO Auto-generated method stub
??String url = "";
??//单击转向按钮
??if(e.getSource() == button){
???//获取地址栏里的内容
???url = jurl.getText();
???//url不为空，并且以http://开头
???if(url.length()>0 && url.startsWith("http://")){
????try{
?????//JEditorPane组件显示url的内容连接
?????jEditorPane1.setPage(url);
?????//将url的内容添加到ArrayList对象history
?????history.add(url);
?????//historyIndex 的数值设为history对象的长度-1
?????historyIndex = history.size()-1;
?????//设置非编辑状态jEditorPane1.setEdittable(false);
?????//重新布局
?????jEditorPane1.revalidate();
????}catch(Exception ex){
?????//如果连接显示失败，则弹出对话框“无法打开该页面”
?????JOptionPane.showMessageDialog(WebBrowser.this, "无法打开该页面","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;
?????//设置非编辑状态jEditorPane1.setEditable(false)
?????jEditorPane1.revalidate();
????}catch(Exception ex){
?????JOptionPane.showMessageDialog(WebBrowser.this, "无法打开该页面","网页浏览器",JOptionPane.ERROR_MESSAGE);
????}
???}
???//没有url，即url为空
???else if(url.length() == 0){
????JOptionPane.showMessageDialog(WebBrowser.this, "请输入地址","网页浏览器",JOptionPane.ERROR_MESSAGE);
???}
??}
??//输入地址后回车
??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;
?????//设置非编辑状态jEditorPane1.setEditable(false);
?????jEditorPane1.revalidate();
?????jurl.setMaximumSize(jurl.getPreferredSize());
????}catch(Exception ex){
?????JOptionPane.showMessageDialog(WebBrowser.this, "无法打开该页面","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;
?????//设置非编辑状态jEditorPane1.setEditable(false);
?????jEditorPane1.revalidate();
????}catch(Exception ex){
?????JOptionPane.showMessageDialog(WebBrowser.this, "无法打开该页面","网页浏览器",JOptionPane.ERROR_MESSAGE);
????}
???}
???else if(url.length() == 0){
????JOptionPane.showMessageDialog(WebBrowser.this, "无法打开该页面","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, "无法打开该页面","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());
????//设置成非编辑状态jEditorPane1.setEditable(false);
????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());
????//设置成非编辑状态jEditorPane1.setEditable(false);
????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为单击“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, "请输入连接地址","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);
?????//设置成非编辑状态jEditorPane1.setEditable(false);
?????jEditorPane1.revalidate();
????}catch(Exception ex){
?????
????}
???}
???else if(url.length()>0 && url.startsWith("http://")){
????url = "http://" + url;
????try{
?????jEditorPane1.setPage(url);
?????//设置成非编辑状态jEditorPane1.setEditable(false);
?????jEditorPane1.revalidate();
????}catch(Exception ex){
?????
????}
???}
??}
?}

?/**
? * 保存文件
? * @param url
? */
?void saveFile(final String url) {
??// TODO Auto-generated method stub
??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(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();
?}
?/**
? * 查看源代码
? */
?void getHtmlSource(String url) {
??// TODO Auto-generated method stub
??String linesep,htmlLine;
??linesep = System.getProperty("line.separtor");
??htmlSource = "";
??try{
???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(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hyperlineUpdate 函数
? */
?public void hyperlinkUpdate(HyperlinkEvent e) {
??// TODO Auto-generated method stub
??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);
?}
}
ViewSourceFrame类

package Browser;
import java.awt.AWTEvent;
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.*;

import javax.swing.*;
import javax.swing.border.Border;
class ViewSourceFrame extends JFrame implements ActionListener{
?JPanel contentPane;
?JPanel panel1 = new JPanel();
?JPanel panel2 = new JPanel();
?Border border1;
?
?JButton closebutton = new JButton();
?JButton savebutton = new JButton();
?JScrollPane jScrollPane1 = new JScrollPane();
?JTextArea jTextArea1 = new JTextArea();
?
?String htmlSource;

?/**
? * 构造函数，初始化图形用户界面
? */
?public ViewSourceFrame(String htmlSource) {
??this.htmlSource = htmlSource;
??enableEvents(AWTEvent.WINDOW_EVENT_MASK);
??setSize(new Dimension(600,500));
??setTitle("源代码");
??setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
??
??contentPane = (JPanel)getContentPane();
??contentPane.setLayout(new BorderLayout());
??
??panel2.setLayout(new FlowLayout());
??
??savebutton.setText("保存");
??closebutton.setText("退出");
??
??closebutton.addActionListener(this);
??savebutton.addActionListener(this);
??
??jScrollPane1.getViewport().add(jTextArea1,null);
??border1 = BorderFactory.createEmptyBorder(4,4,4,4);
??panel1.setLayout(new BorderLayout());
??panel1.setBorder(border1);
??panel1.add(jScrollPane1,BorderLayout.CENTER);
??contentPane.add(panel1,BorderLayout.CENTER);
??
??panel2.add(savebutton);
??panel2.add(closebutton);
??
??contentPane.add(panel2,BorderLayout.SOUTH);
??this.jTextArea1.setEditable(true);
??this.jTextArea1.setText(this.htmlSource);
??//设置光标的位置，将其移动到文本区第0个字符
??this.jTextArea1.setCaretPosition(0);
?}

?/**
? * 实现监听器接口的 ActionEvent 函数
? */
?public void actionPerformed(ActionEvent e) {
??// TODO Auto-generated method stub
??String url="";
??if(e.getSource() == closebutton){
???dispose();
??}
??else if(e.getSource() == savebutton){
???JFileChooser fc = new JFileChooser();
???int returnVal = fc.showSaveDialog(ViewSourceFrame.this);
???File saveFile=fc.getSelectedFile();
???try{
????FileWriter writeOut = new FileWriter(saveFile);
????writeOut.write(jTextArea1.getText());
????writeOut.close();
???}catch(Exception ex){
????System.out.println("保存失败");
???}
??}
?}
}