时间:2021-07-01 10:21:17 帮助过:12人阅读
开发工具:eclipse、kaptcha-2.3.jar包。
一、创建Web项目;
二、新建一个Jsp页面(内容有,一个文本框,一个图片容器,一个提交按钮)
- <body>
- <img alt="random" src="randomcode.jpg" onclick="changeR(this)" style="cursor: pointer;">
- <form action="check.jsp">
- <input type="text" name="r">
- <input type="submit" value="s">
- </form>
- </body>
三、可以看出图片验证码来源(src=“randomcode.jpg”)需配置Web.xml文件。(交给Servlet(该servlet在kaptcha-2.3.jar)处理)
- <servlet>
- <servlet-name>Kaptcha</servlet-name>
- <servlet-class>com.google.code.kaptcha.servlet.KaptchaServlet</servlet-class>
- </servlet>
- <servlet-mapping>
- <servlet-name>Kaptcha</servlet-name>
- <url-pattern>/randomcode.jpg</url-pattern>
- </servlet-mapping>
四、由于需要kaptcha-2.3.jar包,所以将下载好的jar包导入在lib中。(复制黏贴即可)
其他:
一、网页验证码的属性
(一)添加边框
- <servlet>
- <init-param>
- <description>图片边框,合法值:yes , no</description>
- <param-name>kaptcha.border</param-name>
- <param-value>yes</param-value> <!-- yes 或者 no-->
- </init-param>
- </servlet>
(二)边框颜色
- <init-param>
- <description>
- 边框颜色,合法值: r,g,b (and optional alpha) 或者white,black,blue.
- </description>
- <param-name>kaptcha.border.color</param-name>
- <param-value>black</param-value>
- </init-param>
(三)边框厚度
- <init-param>
- <description>边框厚度,合法值:>大于0 </description>
- <param-name>kaptcha.border.thickness</param-name>
- <param-value>1</param-value>
- </init-param>
(四)图片宽度
- <init-param>
- <description>图片宽 200</description>
- <param-name>kaptcha.image.width</param-name>
- <param-value>200</param-value>
- </init-param>
(五)图片高度
- <init-param>
- <description>图片高 50</description>
- <param-name>kaptcha.image.height</param-name>
- <param-value>50</param-value>
- </init-param>
(六)验证码集合
- <init-param>
- <description>文本集合,验证码值从此集合中获取</description>
- <param-name>kaptcha.textproducer.char.string</param-name>
- <param-value>1234567890</param-value> <!--纯数字 -->
- //<param-value>abcde2345678gfynmnpwx</param-value> <!-- 文字加英文-->
- </init-param>
(七)验证码长度
- <init-param>
- <description>验证码长度 默认是5 </description>
- <param-name>kaptcha.textproducer.char.length</param-name>
- <param-value>2</param-value>
- </init-param>
(八)字体
- <init-param>
- <description>字体 Arial, Courier</description>
- <param-name>kaptcha.textproducer.font.names</param-name>
- <param-value>Arial, Courier</param-value>
- </init-param>
(九)字体大小
- <init-param>
- <description>字体大小 40px.</description>
- <param-name>kaptcha.textproducer.font.size</param-name>
- <param-value>40</param-value>
- </init-param>
(十)字体颜色
- <init-param>
- <description>
- 字体颜色,合法值: r,g,b 或者 white,black,blue.
- </description>
- <param-name>kaptcha.textproducer.font.color</param-name>
- <param-value>black</param-value>
- </init-param>
(十一)每个验证码之间的间隔
- <init-param>
- <description>文字间隔 2</description>
- <param-name>kaptcha.textproducer.char.space</param-name>
- <param-value>2</param-value>
- </init-param>
(十二)干扰实现
- <init-param>
- <description>干扰实现类</description>
- <param-name>kaptcha.noise.impl</param-name>
- <param-value>
- <!-- com.google.code.kaptcha.impl.NoNoise -->
- com.google.code.kaptcha.impl.DefaultNoise
- </param-value>
- </init-param>
(十三)干扰颜色
- <init-param>
- <description>
- 干扰颜色,合法值: r,g,b 或者 white,black,blue.
- </description>
- <param-name>kaptcha.noise.color</param-name>
- <param-value>black</param-value>
- </init-param>
(十四)背景样式
- <init-param>
- <description>
- 图片样式: 水纹com.google.code.kaptcha.impl.WaterRipple
- 鱼眼com.google.code.kaptcha.impl.FishEyeGimpy
- 阴影com.google.code.kaptcha.impl.ShadowGimpy
- </description>
- <param-name>kaptcha.obscurificator.impl</param-name>
- <param-value>
- com.google.code.kaptcha.impl.WaterRipple
- </param-value>
- </init-param>
(十五)背景实现类
- <init-param>
- <description>背景实现类</description>
- <param-name>kaptcha.background.impl</param-name>
- <param-value>
- com.google.code.kaptcha.impl.DefaultBackground
- </param-value>
- </init-param>
(十六)背景渐变颜色
- <init-param>
- <description>背景颜色渐变,开始颜色</description>
- <param-name>kaptcha.background.clear.from</param-name>
- <param-value>green</param-value>
- </init-param>
- <init-param>
- <description>背景颜色渐变,结束颜色</description>
- <param-name>kaptcha.background.clear.to</param-name>
- <param-value>white</param-value>
- </init-param>
(十七)文字渲染器
- <init-param>
- <description> 文字渲染器 </description>
- <param-name>kaptcha.word.impl</param-name>
- <param-value>
- com.google.code.kaptcha.text.impl.DefaultWordRenderer
- </param-value>
- </init-param>
(十八)图片的验证码会保存在Session中,其中的值为
- <init-param>
- <description> session中存放验证码的key键 </description>
- <param-name>kaptcha.session.key</param-name>
- <param-value>KAPTCHA_SESSION_KEY</param-value>
- </init-param>
(十九)图片实现类别
- <init-param>
- <description>图片实现类</description>
- <param-name>kaptcha.producer.impl</param-name>
- <param-value>
- com.google.code.kaptcha.impl.DefaultKaptcha
- </param-value>
- </init-param>
(二十)文本实现类(可通过重写该类来实现验证码为中文)
- <init-param>
- <description>文本实现类</description>
- <param-name>kaptcha.textproducer.impl</param-name>
- <param-value>
- com.google.code.kaptcha.text.impl.DefaultTextCreator
- </param-value>
- </init-param>
重写文本实现类,实现验证码为中文:
1.创建一个类别,继承Configurable 实现TextProducer(在jar包中)
- import com.google.code.kaptcha.text.TextProducer;
- import com.google.code.kaptcha.util.Configurable;
- import java.util.Random;
- public class ChineseText extends Configurable implements TextProducer {
- public String getText() {
- int length = getConfig().getTextProducerCharLength();
- String finalWord = "", firstWord = "";
- int tempInt = 0;
- String[] array = { "0", "1", "2", "3", "4", "5", "6", "7", "8", "9",
- "a", "b", "c", "d", "e", "f" };
- Random rand = new Random();
- for (int i = 0; i < length; i++) {
- switch (rand.nextInt(array.length)) {
- case 1:
- tempInt = rand.nextInt(26) + 65;
- firstWord = String.valueOf((char) tempInt);
- break;
- case 2:
- int r1,
- r2,
- r3,
- r4;
- String strH,
- strL;// high&low
- r1 = rand.nextInt(3) + 11; // 前闭后开[11,14)
- if (r1 == 13) {
- r2 = rand.nextInt(7);
- } else {
- r2 = rand.nextInt(16);
- }
- r3 = rand.nextInt(6) + 10;
- if (r3 == 10) {
- r4 = rand.nextInt(15) + 1;
- } else if (r3 == 15) {
- r4 = rand.nextInt(15);
- } else {
- r4 = rand.nextInt(16);
- }
- strH = array[r1] + array[r2];
- strL = array[r3] + array[r4];
- byte[] bytes = new byte[2];
- bytes[0] = (byte) (Integer.parseInt(strH, 16));
- bytes[1] = (byte) (Integer.parseInt(strL, 16));
- firstWord = new String(bytes);
- break;
- default:
- tempInt = rand.nextInt(10) + 48;
- firstWord = String.valueOf((char) tempInt);
- break;
- }
- finalWord += firstWord;
- }
- return finalWord;
- }
- }
2.修改Web.xml配置
- <init-param>
- <description>文本实现类</description>
- <param-name>kaptcha.textproducer.impl</param-name>
- <param-value>
- ChineseText
- </param-value>
- </init-param>
- 五、验证码的校验(本文是利用check.jsp来校验的)保存在Session中,其中的键值为(第十八个属性)
- [html] view plain copy
- <body>
- <%
- // 检查是否是正确的验证码
- String k = (String) session.getAttribute(com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
- String str = request.getParameter("r");
- if (k.equals(str))
- out.print("true");
- out.print(k + "---" + str);
- %>
- </body>
六、扩展(加法验证码的实现)
1.重写KaptchaServlet类
- import com.google.code.kaptcha.Producer;
- import com.google.code.kaptcha.util.Config;
- import java.awt.image.BufferedImage;
- import java.io.IOException;
- import java.util.Enumeration;
- import java.util.Properties;
- import javax.imageio.ImageIO;
- import javax.servlet.Servlet;
- import javax.servlet.ServletConfig;
- import javax.servlet.ServletException;
- import javax.servlet.ServletOutputStream;
- import javax.servlet.http.HttpServlet;
- import javax.servlet.http.HttpServletRequest;
- import javax.servlet.http.HttpServletResponse;
- import javax.servlet.http.HttpSession;
- public class KaptchaServlet extends HttpServlet implements Servlet {
- private Properties props;
- private Producer kaptchaProducer;
- private String sessionKeyValue;
- public KaptchaServlet() {
- this.props = new Properties();
- this.kaptchaProducer = null;
- this.sessionKeyValue = null;
- }
- public void init(ServletConfig conf) throws ServletException {
- super.init(conf);
- ImageIO.setUseCache(false);
- Enumeration initParams = conf.getInitParameterNames();
- while (initParams.hasMoreElements()) {
- String key = (String) initParams.nextElement();
- String value = conf.getInitParameter(key);
- this.props.put(key, value);
- }
- Config config = new Config(this.props);
- this.kaptchaProducer = config.getProducerImpl();
- this.sessionKeyValue = config.getSessionKey();
- }
- public void doGet(HttpServletRequest req, HttpServletResponse resp)
- throws ServletException, IOException {
- resp.setDateHeader("Expires", 0L);
- resp.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
- resp.addHeader("Cache-Control", "post-check=0, pre-check=0");
- resp.setHeader("Pragma", "no-cache");
- resp.setContentType("image/jpeg");
- String capText = this.kaptchaProducer.createText();
- String s1 = capText.substring(0, 1);
- String s2 = capText.substring(1, 2);
- int r = Integer.valueOf(s1).intValue() + Integer.valueOf(s2).intValue();
- req.getSession().setAttribute(this.sessionKeyValue, String.valueOf(r));
- BufferedImage bi = this.kaptchaProducer.createImage(s1+"+"+s2+"=?");
- ServletOutputStream out = resp.getOutputStream();
- ImageIO.write(bi, "jpg", out);
- try {
- out.flush();
- } finally {
- out.close();
- }
- }
- }
2.修改配置文件
- <servlet>
- <servlet-name>Kaptcha</servlet-name>
- <servlet-class>KaptchaServlet</servlet-class>
- </servlet>
以上所述是小编给大家介绍的使用开源工具制作网页验证码的方法,希望对大家有所帮助,如果大家有任何疑问请给我留言,小编会及时回复大家的。在此也非常感谢大家对脚本之家网站的支持!