java网络编程之作业I

来源：互联网发布：net的国外域名编辑：程序博客网时间：2024/06/05 18:40

1.编写图形界面的Application程序,包含一个TextField和一个Label,TextField接受用户的输入的主机名,Label把这个主机的IP地址显示出来.

import java.net.*;import java.awt.event.*;import java.awt.*;import javax.swing.*;public class scannerip implements ActionListener{ String host; InetAddress address; String ip; JButton buttonScan = new JButton("扫描"); JLabel hostnameLabel = new JLabel("主机名称"); JTextField hostTextField = new JTextField(); JLabel hostipLabel = new JLabel("主机IP是"); public scannerip() { JDialog p1=new JDialog(); p1.setTitle("主机扫描小程序"); Container dialogPane=p1.getContentPane(); dialogPane.setLayout(new GridLayout(2,2)); dialogPane.add(hostnameLabel); dialogPane.add(hostTextField); dialogPane.add(buttonScan); dialogPane.add(hostipLabel); p1.setBounds(250,250,400,100); p1.setVisible(true); buttonScan.addActionListener(this); } public void buttonScan_actionPerformed(ActionEvent e){ out("checking scan parameters..."); if (validParameters()) { out("scanning..."); try { address = InetAddress.getByName(host); out("主机IP是"+"(" + ip + ")."); } catch (Exception ex) { if (ex instanceof SecurityException) out(ex.getMessage()); else out("未找到主机IP地址."); } } } private boolean validParameters() { try { host = hostTextField.getText(); address = InetAddress.getByName(host); ip = address.getHostAddress(); } catch (Exception e) { out(e.getMessage()); return false; } return true; } private void out(String msg) { hostipLabel.setText(msg); } public void actionPerformed(ActionEvent e) { buttonScan_actionPerformed(e); } public static void main(String[] args) { new scannerip(); }}

老师给的答案:

import java.awt.*;import javax.swing.*;import java.awt.event.*;import java.net.*;public class Ex15_1 extends WindowAdapter implements ActionListener { JTextField tf; JButton button; JLabel label; public Ex15_1(){ JFrame f=new JFrame("显示IP地址"); Container contentPane=f.getContentPane(); contentPane.setLayout(new GridLayout(2,2)); tf=new JTextField("localhost"); button=new JButton("确定"); label=new JLabel(); contentPane.add(tf); contentPane.add(button); contentPane.add(label); button.addActionListener(this); f.addWindowListener(this); f.setSize(300,100); f.show(); } public void actionPerformed(ActionEvent e){ String str=tf.getText().trim(); try{ InetAddress address=InetAddress.getByName(str); String IPname=address.getHostAddress(); label.setText(IPname); } catch(UnknownHostException ex){ System.out.println("找不到主机IP."); } } public void WindowClosing(WindowEvent e){ System.exit(0); } public static void main(String[] args){ new Ex15_1(); } }

2.编写一个JSP程序,实现刷新页面就显示增加一次访问次数.

程序1:<html> <head><title>网页访问次数统计</title></head> <% int totalCount=0; Object countChange=application.getAttribute("change"); if(countChange!=null) { String countTemp=(String)countChange; totalCount=Integer.parseInt(countTemp); } totalCount=totalCount+1; String countString=String.valueOf(totalCount); Object countState=(Object)countString; application.setAttribute("change",countState); %> <body> <div align="center"> <h1>你是第<%=totalCount%>次访问本页面了.</h1> </div> </body> </html>

程序II:<html><head><title>网页访问次数统计</title></head><body><%Integer count=(Integer)session.getAttribute("COUNT");if ( count==null ) {count = new Integer(1);session.setAttribute("COUNT", count);}else {count = new Integer(count.intValue() + 1);session.setAttribute("COUNT", count);}out.println("您已经是第"+count+"次访问本页面了.");%></body></html>

这是我们的作业题,首先声明一点,我本人对JAVA也蛮喜欢的,不过JAVA不是我的主修,呵呵,我是学C#的,当然了,要是有需要,可能会入主JAVA 这一个,必竟,JAVA很强大,但又比C++好学,虽然有不足之处,上面的程序是我个人写的,界面不怎么样,谁要是有兴趣,改一个不错.