Kaptcha参数介绍

Kaptcha是一个自动生成验证码的组件，在web.xml中配置Servlet时，有各种参数设置。具体如下：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd" id="WebApp_ID" version="3.0">
  <display-name>captcha</display-name>
    <servlet>
        <servlet-name>Kaptcha</servlet-name>
        <servlet-class>com.google.code.kaptcha.servlet.KaptchaServlet</servlet-class>
        <init-param>
            <description>图片边框，合法值  yea  no</description>
            <param-name>kaptcha.border</param-name>
            <param-value>yes</param-value>
        </init-param>
        <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>blue</param-value>
        </init-param>
        <init-param>
            <description>
                边框厚度  合法值  大于0 的整数
            </description>
            <param-name>kaptcha.border.thickness</param-name>
            <param-value>1</param-value>
        </init-param>
        <init-param>
            <description>图片宽度</description>
            <param-name>kaptcha.image.width</param-name>
            <param-value>200</param-value>
        </init-param>
        <init-param>
            <description>图片高度</description>
            <param-name>kaptcha.image.height</param-name>
            <param-value>50</param-value>
        </init-param>
        <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>
        <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>
        <init-param>
            <description>文本集合  验证码的值从此集合中获取</description>
            <param-name>kaptcha.textproducer.char.string</param-name>
            <param-value>1234560789</param-value>
        </init-param>
        <init-param>
            <description>验证码长度  5</description>
            <param-name>kaptcha.textproducer.char.length</param-name>
            <param-value>3</param-value>
        </init-param>
        <init-param>
            <description>字体</description>
            <param-name>kaptcha.textproducer.font.names</param-name>
            <param-value>Console</param-value>
        </init-param>
        <init-param>
            <description>字体大小</description>
            <param-name>kaptcha.textproducer.font.size</param-name>
            <param-value>40</param-value>
        </init-param>
        <init-param>
            <description>字体颜色    合法值 r,g,b  black white  blue</description>
            <param-name>kaptcha.textproducer.font.color</param-name>
            <param-value>blue</param-value>
        </init-param>
        <init-param>
            <description>文字间隔  </description>
            <param-name>kaptcha.textproducer.char.space</param-name>
            <param-value>100</param-value>
        </init-param>

        <init-param>
            <description>干扰实现类</description>
            <param-name>kaptcha.noise.impl</param-name>
            <param-value>
                com.google.code.kaptcha.impl.DefaultNoise
            </param-value>
        </init-param>
        <init-param>
            <description>干扰颜色</description>
            <param-name>kaptcha.noise.color</param-name>
            <param-value>black</param-value>
        </init-param>
        <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.FishEyeGimpy
            </param-value>
        </init-param>
        <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>
        <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>
        <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>
        <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>
        <init-param>
            <description>
                The date the kaptcha is generated is put into the
                HttpSession. This is the key value for that item in the
                session.
            </description>
            <param-name>kaptcha.session.date</param-name>
            <param-value>KAPTCHA_SESSION_DATE</param-value>
        </init-param>
    </servlet>
    <servlet-mapping>
        <servlet-name>Kaptcha</servlet-name>
        <url-pattern>/captcha.jpg</url-pattern>
    </servlet-mapping>
</web-app>