web开发(十) struts2之图片验证码

1、配置前端页面

<!-- 验证码-->
          <div class="form-group " style="padding-left: 9%;" id="show"> 
                  <span class="glyphicon glyphicon-picture pull-left input-group" style="padding-top: 8px;"></span>
                <input type="text" class="form-control col-md-7 pull-left" maxlength="4" id="user.user_code" name="user.user_code" placeholder="验证码" style="100px;margin-left: 2%">
                  <img  alt="" src="Code.action" src="video/Crocodile.jpg" onclick="this.src='Code.action?'+ Math.random();" class="pull-left" style="65px;height: 35px;margin-left: 2%;"/>
                  <small class="control-label pull-left" style="margin-top: 10px;margin-left: 5px;">(点击图片刷新)</small>
                  <label class="control-label pull-left" id="msg_code" style="color: red;margin-top: 3px;margin-left: 5px;"></label>
          </div>

其中  src="Code.action"  onclick="this.src='Code.action?'+ Math.random();"，分别为action的name和每次点击图片都自动刷新一次

2、配置Action

<action name="Code" class="Action.LoginOrRegisterAction" method="getCheckCodePic">
                <result name="success" type="stream"> 
                      <param name="contentType">image/jpeg</param>
                      <param name="input2">inputStream</param> 
                      <param name="bufferSize">2048</param>    
                </result>
           </action>

3、Action实例

 //获取验码图片
    public String getCheckCodePic() {
          int WIDTH = 60;
          int HEIGHT = 20;
         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 str = "0123456789qwertyuiopasdfghjklzxcvbnm";
   
         char[] rand = new char[4];
   
         Random random = new Random();
   
         for (int i = 0; i < 4; i++)
         {
             rand[i] = str.charAt(random.nextInt(36));
         }
   
         String rands =new String(rand);
   
         BufferedImage image = new BufferedImage(WIDTH, HEIGHT,BufferedImage.TYPE_INT_RGB);
   
         Graphics g = image.getGraphics();
   
         // 产生图像
         // 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);
         }
   
         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);
   
         // 结束图像 的绘制 过程， 完成图像
         g.dispose();
   
         ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
   
         try {
             ImageIO.write(image, "jpeg", outputStream);
       
             ByteArrayInputStream input = new ByteArrayInputStream(outputStream.toByteArray());
       
             this.setInputStream(input);
             Map<String, Object> session = ActionContext.getContext().getSession();
             session.put("checkCode", rands);
             input.close();
             outputStream.close();
         } catch (IOException e) {
             // TODO Auto-generated catch block
             e.printStackTrace();
         }
         return SUCCESS;    
    } 

4、另一个Action(进行表单验证，通过获取之前保存Session的key)

//验证用户码是否正确
            Map<String, Object> session1=ActionContext.getContext().getSession();
            if(user.getUser_code()!=null && "".equals(user.getUser_code())==false) {
                String code=(String) session1.get("checkCode");
                if(code.equals(user.getUser_code())==false) {
                    //验证码错误，返回状态值
                    map2.put("LoginStatus", "303");
                    System.out.println("验证码错误");
                    String ReturnData=JSONObject.toJSONString(map2); //把Map集合封装成Json形式的字符串
                    inputStream=new ByteArrayInputStream(ReturnData.getBytes("UTF-8"));
                    return SUCCESS;
                }
                
            }