之前想做一个随机验证码的功能，自己也搜索了一下别人写的代码，然后自己重新用struts2实现了一下，现在将我自己实现代码贴出来！大家有什么意见都可以指出来！

首先是生成随机验证码图片的action：

CreateImageAction:

package com.xiaoluo.action;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;public class CreateImageAction extends ActionSupport{    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;    } 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;    }}

以上是生成随机验证码图片的action，将生成的随机数放到session里，然后页面提交到验证随机数的action:

LoginValidateAction:

package com.xiaoluo.action;import javax.servlet.http.HttpSession;import org.apache.struts2.ServletActionContext;import com.opensymphony.xwork2.ActionSupport;public class LoginValidateAction extends ActionSupport{    private String checkCode;        public String getCheckCode()    {        return checkCode;    }    public void setCheckCode(String checkCode)    {        this.checkCode = checkCode;    }    @Override    public String execute() throws Exception    {        return SUCCESS;    }        @Override    public void validate()    {        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！");        }    }}

下面是struts.xml配置部分代码:

　　　　　　
                     
                          
       image/jpeg                    
       inputStream                
      　　　　　　  
                             
                     
      
       /success.jsp
                      
      
       /login.jsp
                  
     

最后就是jsp部分的代码:

login.jsp:

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><%@ taglib prefix="s" uri="/struts-tags"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%>                      
         
         
             
         
         
                   
带有验证码的登陆界面
        
     
                  用户名:
      
      
        密码    :
      
      
        验证码:
       　　　　　 　　　　　
              
      
      
        
                      
              
       

到此，就完成用struts2生成随机验证码图片以及实现登陆验证啦！