Struts学习笔记5——验证码
图片验证功能
1 创建3 个jsp 页面
tplogin.jsp
说明：所要注意的是<form id="form1" name="form1" method="post" action=" tp.do ">
<td>验证码
<input name="tupian" type="text" id="tupian" />
<img src="image1.jsp"> <a href="tplogin.jsp">换一格${requestScope.tupian}</a></td>
</tr>
<tr>
<td>
Image1.jsp
说明：session.setAttribute("tupian", str) 中的tupian 对应的是
<tr>
<td>验证码
<input name="tupian" type="text" id="tupian" />
<img src="image1.jsp"> <a href=" tplogin.jsp ">换一格</a></td>
</tr>
的tupian
<jsp:useBean id="image" class="dao.ImageEnsure" />
这个是引用一个类生成验证码的图片，对应的是dao包里面的ImageEnsure 这个类
Ok.jsp
ok恭喜你验证成功了
ImageEnsure 类
1个action
Struts-config.xml 文件
1 创建3 个jsp 页面
tplogin.jsp
<%@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>无标题文档</title>
</head>
<body>
<form id="form1" name="form1" method="post" action="tp.do">
<p>用户名:
<label>
<input name="username" type="text" id="username" />
</label>
</p>
<p>密码:
<label>
<input name="password" type="text" id="password" />
</label>
</p>
<p>验证码;
<label>
<input name="tupian" type="text" id="tupian" />
</label>
<td><img src="image1.jsp"/> <a href="tplogin.jsp">换一格${requestScope.tupian}</a></td>
</p>
<p>
<label>
<input type="submit" name="Submit" value="提交" />
</label>
</p>
</form>
</body>
</html>
说明：所要注意的是<form id="form1" name="form1" method="post" action=" tp.do ">
<td>验证码
<input name="tupian" type="text" id="tupian" />
<img src="image1.jsp"> <a href="tplogin.jsp">换一格${requestScope.tupian}</a></td>
</tr>
<tr>
<td>
Image1.jsp
<%@page contentType="image/jpeg; charset=gb2312" %>
<jsp:useBean id="image" class="dao.ImageEnsure" />
adc
<%
String str=image.getEnsure(0,0,response.getOutputStream());//取得真正的验证码信息
session.setAttribute("tupian", str); //将这个真正的验证码信息保存在一个对象当中。以便日后核对
%>
说明：session.setAttribute("tupian", str) 中的tupian 对应的是
<tr>
<td>验证码
<input name="tupian" type="text" id="tupian" />
<img src="image1.jsp"> <a href=" tplogin.jsp ">换一格</a></td>
</tr>
的tupian
<jsp:useBean id="image" class="dao.ImageEnsure" />
这个是引用一个类生成验证码的图片，对应的是dao包里面的ImageEnsure 这个类
Ok.jsp
ok恭喜你验证成功了
ImageEnsure 类
package dao;
import java.io.*;
import java.util.*;
import javax.imageio.*;
import java.awt.*;
import java.awt.image.*;
import javax.imageio.ImageIO;
public class ImageEnsure {
public ImageEnsure() {
}
private char mapTable[] = { 'a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i',
'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8',
'9' };
// 这是一个数据字典，验证码当中的信息都是来自这个数组
public String getEnsure(int width, int height, OutputStream os) {
if (width <= 0)
width = 100;
if (height <= 0)
height = 50;
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
// 获取图形上下文
Graphics g = image.getGraphics();
// 设定背景色
g.setColor(new Color(0xCCCCFF));
g.fillRect(0, 0, width, height); // 用刚才的颜色填充矩形（开始x坐标，开始y坐标，终止x坐标，终止y坐标）
// 画边框
g.setColor(Color.black); // 更改颜色
g.drawRect(0, 0, width - 1, height - 1); // 画个框
// 取随机产生的认证码
String strEnsure = "";
// 4代表4位验证码
for (int i = 0; i < 4; ++i) {
strEnsure += mapTable[(int) (mapTable.length * Math.random())];
}
// 将认证码显示到图象中
g.setColor(Color.black);
g.setFont(new Font("Atlantic Inline", Font.PLAIN, 18)); // 18表示字号
String str = strEnsure.substring(0, 1);
g.drawString(str, 8, 15);
str = strEnsure.substring(1, 2);
g.drawString(str, 20, 17);
str = strEnsure.substring(2, 3);
g.drawString(str, 35, 15);
str = strEnsure.substring(3, 4);
g.drawString(str, 45, 17);
// 随机产生30个干扰点
Random rand = new Random();
for (int i = 0; i < 30; i++) {
int x = rand.nextInt(width);
int y = rand.nextInt(height);
g.drawOval(x, y, 1, 1);
}
// 释放图形上下文
g.dispose();
try {
// 输出图象到页面
ImageIO.write(image, "JPEG", os);
} catch (IOException e) {
return "";
}
return strEnsure;
}
/* public static void main(String []args) { try{ BufferedOutputStream os =
new BufferedOutputStream( new FileOutputStream("c:\\test.jpg"));
new ImageEnsure().getEnsure(100, 200, os); os.flush(); os.close(); }
catch(Exception e) {} }
*/
}
1个action
package action;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.apache.struts.action.Action;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
public class TpAction extends Action {
public ActionForward execute(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response) {
String tupian=request.getParameter("tupian");
HttpSession session=request.getSession();
String a=(String)session.getAttribute("tupian");
if(!(request.getSession().getAttribute("tupian").equals(tupian))){
request.setAttribute("tupian","验证码错误");
return mapping.findForward("nook");
}
String username=request.getParameter("username");
String password=request.getParameter("password");
if(username.equals("11")&&password.equals("11")){
session.setAttribute("username", username);
session.setAttribute("log","ok");
return mapping.findForward("ok");
}
return mapping.findForward("nook");
}
}
Struts-config.xml 文件
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts-config PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 1.2//EN" "http://struts.apache.org/dtds/struts-config_1_2.dtd">
<struts-config>
<data-sources />
<form-beans />
<global-exceptions />
<global-forwards />
<action-mappings >
<action path="/tp" type="action.TpAction">
<forward name="ok" path="/ok.jsp" />
<forward name="nook" path="/tplogin.jsp" />
</action>
</action-mappings>
<message-resources parameter="com.yourcompany.struts.ApplicationResources" />
</struts-config>