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="width:100px;margin-left: 2%">
                   <img  alt="" src="Code.action" src="video/Crocodile.jpg" onclick="this.src='Code.action?'+ Math.random();" class="pull-left" style="width: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>

login.jsp

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>

struts.xml

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;
     } 

LoginOrRegisterAction

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;
                 }

             }

LoginAction