strut2登陆注册验证码

1. 生成图片和验证码

package com.jmu.code;

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.servlet.http.HttpServletResponse;

import javax.servlet.http.HttpSession;

import org.apache.struts2.ServletActionContext; 

import com.opensymphony.xwork2.ActionSupport;

/**

 * 生成图片和验证码类

 *

 * @author Sky

 * @date 2017年3月4日 上午10:18:08

 *

 */

public class CreateImageAction extends ActionSupport

{

    private static final long serialVersionUID = 1L;

    private ByteArrayInputStream inputStream;

    private static int WIDTH = 60;

    private static int HEIGHT = 20;

    public ByteArrayInputStream getInputStream()

    {

        return inputStream;

    }

    public void setInputStream(ByteArrayInputStream inputStream)

    {

        this.inputStream = inputStream;

    }

    /**

     * 产生随机数

     * @return

     */

    private static String createRandom()

    {

        String str = "0123456789qwertyuiopasdfghjklzxcvbnm";

        char[] rands = new char[4];

        Random random = new Random();

        for (int i = 0; i < 4; i++)

        {

            rands[i] = str.charAt(random.nextInt(36));

        }

        return new String(rands);

    }

    private void drawBackground(Graphics g)

    {

        // 画背景

        g.setColor(new Color(0xDCDCDC));

        g.fillRect(0, 0, WIDTH, HEIGHT);

        // 随机产生 120 个干扰点

        for (int i = 0; i < 120; i++)

        {

            int x = (int) (Math.random() * WIDTH);

            int y = (int) (Math.random() * HEIGHT);

            int red = (int) (Math.random() * 255);

            int green = (int) (Math.random() * 255);

            int blue = (int) (Math.random() * 255);

            g.setColor(new Color(red, green, blue));

            g.drawOval(x, y, 1, 0);

        }

    }

    private void drawRands(Graphics g, String rands)

    {

        g.setColor(Color.BLACK);

        g.setFont(new Font(null, Font.ITALIC | Font.BOLD, 18));

        // 在不同的高度上输出验证码的每个字符

        g.drawString("" + rands.charAt(0), 1, 17);

        g.drawString("" + rands.charAt(1), 16, 15);

        g.drawString("" + rands.charAt(2), 31, 18);

        g.drawString("" + rands.charAt(3), 46, 16);

        //System.out.println(rands);

    }

    @Override

    public String execute() throws Exception

    {

        HttpServletResponse response = ServletActionContext.getResponse();

        // 设置浏览器不要缓存此图片

        response.setHeader("Pragma", "no-cache");

        response.setHeader("Cache-Control", "no-cache");

        response.setDateHeader("Expires", 0);

        String rands = createRandom();

        BufferedImage image = new BufferedImage(WIDTH, HEIGHT,

                BufferedImage.TYPE_INT_RGB);

        Graphics g = image.getGraphics();

        // 产生图像

        drawBackground(g);

        drawRands(g, rands);

        // 结束图像的绘制过程， 完成图像

        g.dispose();

        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();

        ImageIO.write(image, "jpeg", outputStream);

        ByteArrayInputStream input = new ByteArrayInputStream(outputStream

                .toByteArray());

        this.setInputStream(input);

        HttpSession session = ServletActionContext.getRequest().getSession();

        session.setAttribute("checkCode", rands);

        input.close();

        outputStream.close();

        return SUCCESS;

    }

}

2. 前台jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"

    pageEncoding="UTF-8"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">

<html>

<head>

<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">

<title>Insert title here</title>

<script type="text/javascript">

    function refreshImage(obj){

        /**

          * 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="createImageAction.action?" + timeNow;

    }

</script>

</head>

<body>

<form action="loginValidateAction" method="post">

        <!--若要点击图片刷新，重新得到一个验证码，要在后面加上个随机数，这样保证每次提交过去的都是不一样的path，防止因为缓存而使图片不刷新-->

        验证码：<input type="text" name="checkCode" />

        <img src="createImageAction.action" onclick="refreshImage(this)" title="点击图片刷新验证码" />

        <br>

        <button>提交</button>

    </form>

</body>

</html>

3. strut2.xml

<?xml version="1.0" encoding="UTF-8" ?>

<!DOCTYPE struts PUBLIC

    "-//Apache Software Foundation//DTD Struts Configuration 2.3//EN"

    "http://struts.apache.org/dtds/struts-2.3.dtd">

<struts>

<package name="default" namespace="/" extends="struts-default">

    <action name="createImageAction" class="com.jmu.code.CreateImageAction" method="execute">

        <result name="success" type="stream">

            <param name="contentType">image/jpeg</param>

            <param name="inputName">inputStream</param>

        </result>

    </action>

    <action name="loginValidateAction" class="com.jmu.code.LoginValidateAction">

        <result name="success">/success.jsp</result>

        <result name="input">/login.jsp</result>

    </action>

</package>

</struts>

4. web.xml 要加上strut2的过滤

<?xml version="1.0" encoding="UTF-8"?>

<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"

    xmlns="http://java.sun.com/xml/ns/javaee"

    xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"

    id="WebApp_ID" version="3.0">

    <display-name>code</display-name>

    <filter>

        <filter-name>struts2</filter-name>

        <filter-class>org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter</filter-class>

    </filter>

    <filter-mapping>

        <filter-name>struts2</filter-name>

        <url-pattern>/*</url-pattern>

    </filter-mapping>

</web-app>

5. 后台检查输入验证码是否正确

package com.jmu.code;

import javax.servlet.http.HttpSession;

import org.apache.struts2.ServletActionContext;

import com.opensymphony.xwork2.ActionSupport;

public class LoginValidateAction extends ActionSupport

{

    private static final long serialVersionUID = 1L;

    private String checkCode;

    @Override

    public String execute() throws Exception

    {

        if(checkCode()){

            System.out.println("check success");

        }else {

            System.out.println("check false");

        }

        return SUCCESS;

    }

    /**

     * 验证验证码是否正确

     * @return true or false

     */

    public boolean checkCode()

    {

        HttpSession session = ServletActionContext.getRequest().getSession();

        String checkCode2 = (String)session.getAttribute("checkCode");

        if(!checkCode.equals(checkCode2))

        {

            this.addActionError("输入的验证码不正确，请重新输入！");

            return false;

        }

        return true;

    }

    public String getCheckCode()

    {

        return checkCode;

    }

    public void setCheckCode(String checkCode)

    {

        this.checkCode = checkCode;

    }

}

目录结构：

巴特西

strut2登陆注册验证码

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