验证码例子（jcaptcha插件的使用）
和上一篇验证码的例子（kaptcha插件的使用）类似，同样加进了spring mvc、jquery
项目目录结构：
pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.royal</groupId>
<artifactId>verifyCode_jcaptcha</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>verifyCode_jcaptcha</name>
<url>http://maven.apache.org</url>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<!-- 需要用到的jar -->
<dependency>
<groupId>com.octo.captcha</groupId>
<artifactId>jcaptcha-all</artifactId>
<version>1.0-RC6</version>
</dependency>
<!-- spring mvc -->
<dependency>
<groupId>commons-logging</groupId>
<artifactId>commons-logging</artifactId>
<version>1.1.1</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aop</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-asm</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-aspects</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-beans</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context-support</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-core</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-expression</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-instrument</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jms</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-orm</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-oxm</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-test</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-tx</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-web</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-webmvc-portlet</artifactId>
<version>3.1.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.apache.tomcat</groupId>
<artifactId>jsp-api</artifactId>
<version>6.0.35</version>
</dependency>
</dependencies>
</project>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>jcaptcha</servlet-name>
<servlet-class>com.royal.servlet.ImageCaptchaServlet</servlet-class>
<load-on-startup>0</load-on-startup>
</servlet>
<servlet>
<servlet-name>mvc-dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<load-on-startup>1</load-on-startup>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>/WEB-INF/spring-mvc.xml</param-value>
</init-param>
</servlet>
<!-- MVC不过滤以下文件 -->
<servlet-mapping>
<servlet-name>default</servlet-name>
<url-pattern>*.css</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>default</servlet-name>
<url-pattern>*.gif</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>default</servlet-name>
<url-pattern>*.jpg</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>default</servlet-name>
<url-pattern>*.js</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>jcaptcha</servlet-name>
<url-pattern>/jcaptcha</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>mvc-dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
spring-mvc.xml
<beans xmlns:context="http://www.springframework.org/schema/context"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://www.springframework.org/schema/beans"
xsi:schemaLocation="
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd" >
<context:component-scan base-package="com.royal.controller"/>
<bean name="/verifyJcaptcha" class="com.royal.controller.VerifyJcaptchaController" />
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" >
<property name="prefix" value="/"/>
<property name="suffix" value=".jsp"/>
</bean>
</beans>
CaptchaServiceSingleton.java
package com.royal.verifyCode_jcaptcha;
import com.octo.captcha.service.image.DefaultManageableImageCaptchaService;
import com.octo.captcha.service.image.ImageCaptchaService;
/**
* 实例一个jcaptcha服务，注意，必须是单例模式
*/
public class CaptchaServiceSingleton {
private static ImageCaptchaService instance = new DefaultManageableImageCaptchaService();
public static ImageCaptchaService getInstance(){
return instance;
}
}
ImageCaptchaServlet.java
package com.royal.servlet;
import java.awt.image.BufferedImage;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
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 com.royal.verifyCode_jcaptcha.CaptchaServiceSingleton;
import com.sun.image.codec.jpeg.JPEGCodec;
import com.sun.image.codec.jpeg.JPEGImageEncoder;
/**
* 一个产生图片的servlet
*/
public class ImageCaptchaServlet extends HttpServlet{
private static final long serialVersionUID = 1L;
@Override
public void init(ServletConfig config) throws ServletException {
super.init(config);
}
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doPost(req, resp);
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
byte[] captchaChallengeAsJpeg = null;
//the output stream to render the captcha image as jpeg into
ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();
//get the session id that will identify the generated captcha.the same id must be used to validate the response, the session id is a good candidate!
String captchaId = req.getSession().getId();
//call the ImageCaptchaService getChallenge method
BufferedImage challenge = CaptchaServiceSingleton.getInstance().getImageChallengeForID(captchaId, req.getLocale());
//a jpeg encoder
JPEGImageEncoder jpegEncoder = JPEGCodec.createJPEGEncoder(jpegOutputStream);
jpegEncoder.encode(challenge);
captchaChallengeAsJpeg = jpegOutputStream.toByteArray();
// flush it in the response
resp.setHeader("Cache-Control", "no-store");
resp.setHeader("Pragma", "no-cache");
resp.setDateHeader("Expires", 0);
resp.setContentType("image/jpeg");
ServletOutputStream responseOutputStream = resp.getOutputStream();
responseOutputStream.write(captchaChallengeAsJpeg);
responseOutputStream.flush();
responseOutputStream.close();
}
}
也就是当你点击图片进行刷新的时候，访问的就是这个servlet（用于生成验证码图片）
这里可能有个小问题:
当你要用 JPEGImageEncoder 和 JPEGCodec，你会发现无法导入rt.jar里面的 com.sun.image.codec.jpeg.JPEGCodec
com.sun.image.codec.jpeg.JPEGImageEncoder
这两个类
解决办法：deprecated and restricted API--- Forbidden 选项改为warning
参考：http://blog.csdn.net/oney139/article/details/6539624
mvc 控制类
VerifyJcaptchaController.java
package com.royal.controller;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.springframework.web.servlet.ModelAndView;
import org.springframework.web.servlet.mvc.AbstractController;
import com.royal.verifyCode_jcaptcha.CaptchaServiceSingleton;
public class VerifyJcaptchaController extends AbstractController{
@Override
protected ModelAndView handleRequestInternal(HttpServletRequest request, HttpServletResponse response) throws Exception {
Boolean isResponseCorrect = Boolean.FALSE;
//remenber that we need an id to validate!
String captchaId = request.getSession().getId();
System.out.println("captchaId---" + captchaId);
//retrieve the response
String resp = request.getParameter("j_captcha_response");
System.out.println("j_captcha_response---" + resp);
// Call the Service method
isResponseCorrect = CaptchaServiceSingleton.getInstance().validateResponseForID(captchaId, resp);
System.out.println("isResponseCorrect---" + isResponseCorrect);
if(isResponseCorrect == true){
return new ModelAndView("success");
}else{
System.out.println("FAIL..");
return null;
}
}
}
同样别忘了maven build...
启动tomcat，访问：http://localhost:8080/verifyCode_jcaptcha/
demo算是demo完了，但总觉得变扭，图片好像不怎么好看，图片大小不知道怎么改。API没看。
官方：http://jcaptcha.sourceforge.net/
千篇一律的这个不完整例子 参考：http://www.blogjava.net/alex/archive/2006/06/11/51976.html