登陆验证码(struts2实现)
登陆验证码(struts2实现)
1.login.jsp
2.web.xml
3.struts.xml
4.RandomNumUtil.java
5.RandomAction.java和LoginAction.java
1.login.jsp
<%@ page language="java" import="java.util.*" pageEncoding="GBK"%>
<%@ taglib prefix ="s" uri="/struts-tags"%>
<html>
<head>
<script type="text/javascript">
function changeValidateCode(obj) {
/***
* 获取当前的时间作为参数，无具体意义
* 每次请求需要一个不同的参数，否则可能会返回同样的验证码
* 这和浏览器的缓存机制有关系，也可以把页面设置为不缓存，这样就不用这个参数了。
*/
var timenow = new Date().getTime();
obj.src="randPic.action?d="+timenow;
}
</script>
</head>
<body>
<form name="" action="Login">
验证码：<s:textfield name="code"></s:textfield><img src="randPic.action" onclick="changeValidateCode(this)" title="点击图片刷新验证码"/>
<br/><input type="submit" value="登陆"/><input type="reset" value="重置"/>
</form>
</body>
</html>
2.web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.4"
xmlns="http://java.sun.com/xml/ns/j2ee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee
http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
</web-app>
3.struts.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
<package name="iamge" extends="struts-default" namespace="/">
<action name="randPic" class="com.org.momo.action.RandomAction">
<result type="stream">
<param name="contentType">image/jpeg</param>
<param name="inputName">inputStream</param>
</result>
</action>
<action name="Login" class="com.org.momo.action.LoginAction">
<result name="success">/success.jsp</result>
<result name="error">/fail.jsp</result>
</action>
</package>
</struts>
4.RandomNumUtil.java
package com.org.momo.util ;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.imageio.stream.ImageOutputStream;
public class RandomNumUtil {
private ByteArrayInputStream image;//图像
private String str;//验证码
private RandomNumUtil(){
init();//初始化属性
}
/*
* 取得RandomNumUtil实例
*/
public static RandomNumUtil Instance(){
return new RandomNumUtil();
}
/*
* 取得验证码图片
*/
public ByteArrayInputStream getImage(){
return this.image;
}
/*
* 取得图片的验证码
*/
public String getString(){
return this.str;
}
private void init() {
// 在内存中创建图象
int width=85, height=20;
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
// 获取图形上下文
Graphics g = image.getGraphics();
// 生成随机类
Random random = new Random();
// 设定背景色
g.setColor(getRandColor(200,250));
g.fillRect(0, 0, width, height);
// 设定字体
g.setFont(new Font("Times New Roman",Font.PLAIN,18));
// 随机产生155条干扰线，使图象中的认证码不易被其它程序探测到
g.setColor(getRandColor(160,200));
for (int i=0;i<155;i++)
{
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x,y,x+xl,y+yl);
}
// 取随机产生的认证码(6位数字)
String sRand="";
for (int i=0;i<4;i++){
String rand=String.valueOf(random.nextInt(10));
sRand+=rand;
// 将认证码显示到图象中
g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));
// 调用函数出来的颜色相同，可能是因为种子太接近，所以只能直接生成
g.drawString(rand,13*i+6,16);
}
//赋值验证码
this.str=sRand;
//图象生效
g.dispose();
ByteArrayInputStream input=null;
ByteArrayOutputStream output = new ByteArrayOutputStream();
try{
ImageOutputStream imageOut = ImageIO.createImageOutputStream(output);
ImageIO.write(image, "JPEG", imageOut);
imageOut.close();
input = new ByteArrayInputStream(output.toByteArray());
}catch(Exception e){
System.out.println("验证码图片产生出现错误："+e.toString());
}
this.image=input;/* 赋值图像 */
}
/*
* 给定范围获得随机颜色
*/
private Color getRandColor(int fc,int bc){
Random random = new Random();
if(fc>255) fc=255;
if(bc>255) bc=255;
int r=fc+random.nextInt(bc-fc);
int g=fc+random.nextInt(bc-fc);
int b=fc+random.nextInt(bc-fc);
return new Color(r,g,b);
}
}
5.RandomAction.java和LoginAction.java
package com.org.momo.action ;
import java.io.ByteArrayInputStream;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
import com.org.momo.util.RandomNumUtil;
public class RandomAction extends ActionSupport{
private ByteArrayInputStream inputStream;
public String execute() throws Exception{
RandomNumUtil rdnu=RandomNumUtil.Instance();
this.setInputStream(rdnu.getImage());//取得带有随机字符串的图片
ActionContext.getContext().getSession().put("sessionCode", rdnu.getString());//取得随机字符串放入HttpSession
return SUCCESS;
}
public void setInputStream(ByteArrayInputStream inputStream) {
this.inputStream = inputStream;
}
public ByteArrayInputStream getInputStream() {
return inputStream;
}
}
package com.org.momo.action;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
public class LoginAction extends ActionSupport{
private String code;
public String getCode() {
return code;
}
public void setCode(String code) {
this.code = code;
}
public String execute() throws Exception{
String sessionCode=(String)(ActionContext.getContext().getSession().get("sessionCode"));
if(sessionCode.equals(this.getCode())) {
return SUCCESS;
}else{
return ERROR;
}
}
}