webbrowser.java

这是《Java案例精粹150例（上册）》一书配套的源代码。

import java.io.IOException;
import java.net.URL;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.event.*;

public class WebBrowser extends JFrame {
	JPanel contentPane; // 包含整个框架的容器
	BorderLayout borderLayoutAll = new BorderLayout();
	JLabel jLabelPrompt = new JLabel(); // 状态提示框
	JPanel jPanelMain = new JPanel();
	BorderLayout borderLayoutMain = new BorderLayout();
	JTextField textFieldURL = new JTextField(); // URL输入框
	JEditorPane jEditorPane = new JEditorPane(); // 显示网页内容的容器

	public WebBrowser() { // 定义构造方法
		try {
			Init(); // 初始化并显示界面
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	private void Init() throws Exception { // 界面初始化
		contentPane = (JPanel) getContentPane();
		contentPane.setLayout(borderLayoutAll);
		jPanelMain.setLayout(borderLayoutMain);
		jLabelPrompt.setText("请输入URL");
		textFieldURL.setText(""); // 清空文本框
		textFieldURL.addActionListener(new java.awt.event.ActionListener() {
			public void actionPerformed(ActionEvent e) {
				textFieldURL_actionPerformed(e);
			}
		});
		jEditorPane.setEditable(false); // 设置不可编辑
		jEditorPane
				.addHyperlinkListener(new javax.swing.event.HyperlinkListener() {
					public void hyperlinkUpdate(HyperlinkEvent e) {
						jEditorPane_hyperlinkUpdate(e);
					}
				});
		JScrollPane scrollPane = new JScrollPane();
		scrollPane.getViewport().add(jEditorPane);
		jPanelMain.add(textFieldURL, "North");
		jPanelMain.add(scrollPane, "Center");
		contentPane.add(jLabelPrompt, "North");
		contentPane.add(jPanelMain, "Center");
		enableEvents(AWTEvent.WINDOW_EVENT_MASK);
		this.setSize(new Dimension(600, 500));
		this.setTitle("迷你IE ");
		this.setVisible(true);
	}

	void textFieldURL_actionPerformed(ActionEvent e) { // 输入地址后响应回车
		try {
			jEditorPane.setPage(textFieldURL.getText()); // 显示URL
		} catch (IOException ex) {
			JOptionPane msg = new JOptionPane();
			JOptionPane.showMessageDialog(this, "URL地址不正确："
					+ textFieldURL.getText(), "输入不正确！", 0);
		}
	}

	void jEditorPane_hyperlinkUpdate(HyperlinkEvent e) { // 响应页面打开超链接消息
		if (e.getEventType() == javax.swing.event.HyperlinkEvent.EventType.ACTIVATED) {
			try {
				URL url = e.getURL(); // 从消息中得到URL
				jEditorPane.setPage(url); // 显示页面内容
				textFieldURL.setText(url.toString()); // 显示URL
			} catch (IOException io) {
				JOptionPane msg = new JOptionPane();
				JOptionPane.showMessageDialog(this, "打开该链接失败！", "输入不正确！", 0);
			}
		}
	}

	protected void processWindowEvent(WindowEvent e) { //处理窗体事件
		super.processWindowEvent(e);
		if (e.getID() == WindowEvent.WINDOW_CLOSING) {
			System.exit(0); // 关闭
		}
	}

	public static void main(String[] args) { // Main函数
		new WebBrowser();
	}
}