注册页面 注册码【欠缺较多 待完善】

【欠缺较多 待完善】

【web.xml】

<servlet>
<servlet-name>captchaServlet</servlet-name>
<servlet-class>com.jspxcms.common.captcha.CaptchaServlet</servlet-class>
</servlet>

<servlet-mapping>
<servlet-name>captchaServlet</servlet-name>
<url-pattern>/captcha.servlet</url-pattern>
</servlet-mapping>

【验证码工具类】

package com.jspxcms.common.captcha;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpSession;

import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import com.octo.captcha.service.CaptchaService;
import com.octo.captcha.service.CaptchaServiceException;

/**
 * 验证码工具类
 * 
 * @author liufang
 * 
 */
public abstract class Captchas {
    protected static final Logger logger = LoggerFactory
            .getLogger(Captchas.class);

    public static boolean isValid(CaptchaService service,
            HttpServletRequest request, String captcha) {
        HttpSession session = request.getSession(false);
        if (session == null) {
            return false;
        }
        try {
            return service.validateResponseForID(session.getId(), captcha);
        } catch (CaptchaServiceException e) {
            logger.warn("captcha exception", e);
            return false;
        }
    }

    public static boolean isValidTry(MyImageCaptchaService service,
            HttpServletRequest request, String captcha) {
        return isValidTry(service, request, captcha, false);
    }

    public static boolean isValidTry(MyImageCaptchaService service,
            HttpServletRequest request, String captcha, boolean removeOnError) {
        if (StringUtils.isBlank(captcha)) {
            return false;
        }
        HttpSession session = request.getSession(false);
        if (session == null) {
            return false;
        }
        try {
            return service.tryResponseForID(session.getId(), captcha,
                    removeOnError);
        } catch (CaptchaServiceException e) {
            logger.warn("captcha exception", e);
            return false;
        }
    }
}

【验证码servlet】

package com.jspxcms.common.captcha;

import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Locale;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.commons.lang3.StringUtils;
import org.springframework.context.ApplicationContext;
import org.springframework.web.context.support.WebApplicationContextUtils;

import com.jspxcms.common.web.Servlets;

/**
 * 验证码Servlet
 * 
 * @author liufang
 * 
 */
public class CaptchaServlet extends HttpServlet {
    private static final long serialVersionUID = 1L;
    public static final String DEFAULT_CAPTCHA_SERVICE_ID = "captchaService";
    public static final String CAPTCHA_SERVICE_ID = "captchaServiceId";
    private MyImageCaptchaService captchaService;

    @Override
    public void init() throws ServletException {
        String captchaServiceId = getInitParameter(CAPTCHA_SERVICE_ID);
        if (StringUtils.isBlank(captchaServiceId)) {
            captchaServiceId = DEFAULT_CAPTCHA_SERVICE_ID;
        }
        ApplicationContext context = WebApplicationContextUtils
                .getWebApplicationContext(getServletContext());
        captchaService = context.getBean(captchaServiceId,
                MyImageCaptchaService.class);
    }

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        String captcha = req.getParameter("captcha");
        if (captcha == null) {
            challenge(req, resp);
        } else {
            tryResponse(captcha, req, resp);
        }
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        doGet(req, resp);
    }

    private void challenge(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        // Set to expire far in the past.
        resp.setDateHeader("Expires", 0);
        // Set standard HTTP/1.1 no-cache headers.
        resp.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
        // Set IE extended HTTP/1.1 no-cache headers (use addHeader).
        resp.addHeader("Cache-Control", "post-check=0, pre-check=0");
        // Set standard HTTP/1.0 no-cache header.
        resp.setHeader("Pragma", "no-cache");
        // return a jpeg
        resp.setContentType("image/jpeg");

        ServletOutputStream out = resp.getOutputStream();

        try {
            String captchaId = req.getSession(true).getId();
            // create the image with the text
            BufferedImage challenge = captchaService.getImageChallengeForID(
                    captchaId, Locale.ENGLISH);
            // write the data out
            ImageIO.write(challenge, "jpg", out);
            out.flush();
        } finally {
            out.close();
        }
    }

    private void tryResponse(String captcha, HttpServletRequest req,
            HttpServletResponse resp) {
        boolean removeOnError = "true"
                .equals(req.getParameter("removeOnError"));
        if (Captchas.isValidTry(captchaService, req, captcha, removeOnError)) {
            Servlets.writeHtml(resp, "true");
        } else {
            Servlets.writeHtml(resp, "false");
        }
    }
}

【验证码页面】

                    <div class="labelbox">
                        <span>验证码:</span>
                        <p>
                            <input type="text" id="captcha" name="captcha"  data-rule-required="true" data-rule-remote='{"url":"${ctx}/captcha.servlet","type":"post"}' data-msg-remote="验证码错误" autocomplete="off" value=""/><em>请填写验证码</em>
                            <img src="${ctx}/captcha.servlet" onclick="this.src='${ctx}/captcha.servlet?d='+new Date()*1;$('#captcha').focus();" style="cursor:pointer;border:1px solid #ccc;margin: 4px 0 0 7px;vertical-align:top;" title="点击重新获取验证码"/>
                        </p>
                    </div>
原文地址:https://www.cnblogs.com/dixinyunpan/p/5853956.html