使用kaptcha验证码组件操作演示

1、创建一个Maven项目

2、在pom.xml中引入相关依赖

 <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/maven-v4_0_0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <groupId>com.wisezone</groupId>
   <artifactId>wdh_kaptcha</artifactId>
   <packaging>war</packaging>
   <version>0.0.1-SNAPSHOT</version>
   <name>wdh_kaptcha Maven Webapp</name>
   <url>http://maven.apache.org</url>

    <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
       <!-- 定义spring的版本变量在dependency里面直接引用 -->
     <spring.version>4.3.2.RELEASE</spring.version>
     <slf4j.version>1.7.2</slf4j.version>
   </properties>

   <dependencies>
         <!-- spring mvc -->
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-webmvc</artifactId>
             <version>${spring.version}</version>
         </dependency>
         <!-- web开发要有servlet -->
         <dependency>
             <groupId>javax.servlet</groupId>
             <artifactId>javax.servlet-api</artifactId>
             <version>3.0.1</version>
         </dependency>

         <!-- 日志打印相关的jar -->
         <dependency>
             <groupId>org.slf4j</groupId>
             <artifactId>slf4j-log4j12</artifactId>
             <version>${slf4j.version}</version>
         </dependency>
         <dependency>
             <groupId>org.slf4j</groupId>
             <artifactId>slf4j-api</artifactId>
             <version>${slf4j.version}</version>
         </dependency>

44         <!-- 验证码的生成 -->
45         <dependency>
46             <groupId>com.github.axet</groupId>
47             <artifactId>kaptcha</artifactId>
48             <version>0.0.9</version>
49         </dependency>
   </dependencies>
    <build>
         <finalName>wdh_kaptcha</finalName>
         <!-- 资源文件的设置 -->
         <resources>
             <resource>
                 <directory>src/main/resources</directory>
             </resource>
             <resource>
                 <directory>src/main/java</directory>
                 <includes>
                     <include>**/*.properties</include>
                     <include>**/*.xml</include>
                 </includes>
                 <!-- 是否替换资源中的属性 -->
                 <filtering>false</filtering>
             </resource>
         </resources>
         <plugins>
             <!-- compiler plugin -->
             <plugin>
                 <groupId>org.apache.maven.plugins</groupId>
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>2.3.2</version>
                 <configuration>
                     <source>1.7</source>
                     <target>1.7</target>
                     <encoding>UTF-8</encoding>
                     <compilerArguments>
                         <bootclasspath>${java.home}/lib/rt.jar</bootclasspath>
                     </compilerArguments>
                 </configuration>
             </plugin>
             <plugin>
                 <groupId>org.eclipse.jetty</groupId>
                 <artifactId>jetty-maven-plugin</artifactId>
                 <version>9.2.1.v20140609</version>
             </plugin>
         </plugins>
     </build>
 </project>

3、启动WEB容器要在web.xml中配置前端控制器（DispatcherServlet）

 <?xml version="1.0" encoding="UTF-8"?>
 <web-app id="WebApp_ID" version="3.0"
     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_3_0.xsd">
   <servlet>
         <servlet-name>appServlet</servlet-name>
         <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
         <init-param>
             <param-name>contextConfigLocation</param-name>
             <param-value>classpath:*.xml</param-value>
         </init-param>
         <!-- 表示启动容器时初始化该Servlet -->
         <load-on-startup>1</load-on-startup>

     </servlet>

     <servlet-mapping>
         <servlet-name>appServlet</servlet-name>
         <!-- 这是拦截请求, /代表拦截所有请求, 也可以是.html或者.action这类的 -->
         <url-pattern>/</url-pattern>
     </servlet-mapping>

     <filter>
         <filter-name>CharacterEncodingFilter</filter-name>
         <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
         <init-param>
             <param-name>encoding</param-name>
             <param-value>UTF-8</param-value>
         </init-param>
     </filter>
     <filter-mapping>
         <filter-name>CharacterEncodingFilter</filter-name>
         <url-pattern>/*</url-pattern>
     </filter-mapping>
 </web-app>

4、src/main/resources中配置相关信息

a、log4j.properties

 log4j.rootLogger=DEBUG, Console  

 #Console
 log4j.appender.Console=org.apache.log4j.ConsoleAppender
 log4j.appender.Console.layout=org.apache.log4j.PatternLayout
 log4j.appender.Console.layout.ConversionPattern=%d [%t] %-5p [%c] - %m%n  

 log4j.logger.java.sql.ResultSet=INFO
 log4j.logger.org.apache=INFO
 log4j.logger.java.sql.Connection=DEBUG
 log4j.logger.java.sql.Statement=DEBUG
 log4j.logger.java.sql.PreparedStatement=DEBUG 

b、servlet-context.xml

 <?xml version="1.0" encoding="UTF-8"?>
 <beans xmlns="http://www.springframework.org/schema/beans"
     xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xmlns:context="http://www.springframework.org/schema/context"
     xmlns:p="http://www.springframework.org/schema/p"
     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">

     <!-- 扫描package方便注解依赖注入-->
     <context:component-scan base-package="com.wisezone" />

13     <!--图片验证码配置 -->
14     <bean id="captchaProducer" class="com.google.code.kaptcha.impl.DefaultKaptcha">
15         <property name="config">
16             <bean class="com.google.code.kaptcha.util.Config">
17                 <constructor-arg>
18                     <props>
19                         <prop key="kaptcha.border">yes</prop><!--是否有边框 -->
20                         <prop key="kaptcha.border.color">105,179,90</prop><!--设置边框颜色 -->
21                         <prop key="kaptcha.textproducer.font.color">green</prop><!--验证码文本字符颜色 默认为Color.BLACK -->
22                         <prop key="kaptcha.session.key">code</prop><!--验证码 -->
23                         <prop key="kaptcha.textproducer.font.names">宋体,楷体,微软雅黑</prop><!--设置字体样式 -->
24                         <prop key="kaptcha.border.thickness"></prop><!--边框粗细度 默认为1 -->
25                         <prop key="kaptcha.producer.impl"></prop><!--验证码生成器 默认为DefaultKaptcha -->
26                         <prop key="kaptcha.textproducer.impl"></prop><!-- 验证码文本生成器 默认为DefaultTextCreator -->
27                         <prop key="kaptcha.textproducer.char.string"></prop><!--验证码文本字符内容范围 默认为abcde2345678gfynmnpwx -->
28                         <prop key="kaptcha.textproducer.char.length">4</prop><!-- 验证码文本字符长度 默认为5 -->
29                         <prop key="kaptcha.textproducer.font.size">50</prop><!--验证码文本字符大小 默认为40 -->
30                         <prop key="kaptcha.textproducer.char.space">6</prop>    <!--验证码文本字符间距 默认为2 -->
31                         <prop key="kaptcha.image.width">200</prop>    <!--验证码图片宽度 默认为200 -->
32                         <prop key="kaptcha.image.height">60</prop> <!--验证码图片高度 默认为40 -->
33                     </props>
34                 </constructor-arg>
35             </bean>
36         </property>
37     </bean>

 </beans>

5、Demo演示

KaptchaController.java

 package com.wisezone.kaptcha;

 import java.awt.image.BufferedImage;

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

 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.RequestMapping;

 import com.google.code.kaptcha.Constants;
 import com.google.code.kaptcha.Producer;

 @Controller
 @RequestMapping("kaptcha")
 public class KaptchaController {

     @Autowired
     private Producer captchaProducer;

     @RequestMapping("getKaptchaImage")
     public void getKaptchaImage(HttpServletRequest request,
             HttpServletResponse response) throws Exception {

         response.setDateHeader("Expires", 0); 

         // Set standard HTTP/1.1 no-cache headers.
         response.setHeader("Cache-Control", "no-store, no-cache, must-revalidate");
         // Set IE extended HTTP/1.1 no-cache headers (use addHeader).
         response.addHeader("Cache-Control", "post-check=0, pre-check=0");
         // Set standard HTTP/1.0 no-cache header.
         response.setHeader("Pragma", "no-cache");
         // return a jpeg
         response.setContentType("image/jpeg");
         // create the text for the image
         String capText = captchaProducer.createText();
         // store the text in the session
         request.getSession().setAttribute(Constants.KAPTCHA_SESSION_KEY, capText);
         // create the image with the text
         BufferedImage bi = captchaProducer.createImage(capText);
         ServletOutputStream out = response.getOutputStream();
         // write the data out
         ImageIO.write(bi, "jpg", out);
         try {
             out.flush();
         } finally {
             out.close();
         }
     }
 }

6、启动容器查看结果：

浏览器：http://localhost:8080/kaptcha/getKaptchaImage