使用Kaptcha实现JAVA验证码

我不是女神ヾ 2022-05-14 09:21 215阅读 0赞

第一步导入jar包，放入pom.xml文件

<dependencies>
        
        <dependency>
            <groupId>com.github.penggle</groupId>
            <artifactId>kaptcha</artifactId>
            <version>2.3.2</version>
        </dependency>
    </dependencies>

第二步在web.xml中配置生成映射

<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
             xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
             xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
                          http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
             version="3.1" metadata-complete="true">
             
        
        <display-name>Archetype Created Web Application</display-name>
        
        <welcome-file-list>
            <welcome-file>index.jsp</welcome-file>
            <welcome-file>index.html</welcome-file>
        </welcome-file-list>
        
        
        <servlet>
        	<servlet-name>Kaptcha</servlet-name>
        	<servlet-class>com.google.code.kaptcha.servlet.KaptchaServlet</servlet-class>
        	
        	<init-param>
        		<param-name>kaptcha.border</param-name>
        		<param-value>no</param-value>
        	</init-param>
        	
        	<init-param>
        		<param-name>kaptcha.textproducer.font.color</param-name>
        		<param-value>red</param-value>
        	</init-param>
        	
        	<init-param>
        		<param-name>kaptcha.image.width</param-name>
        		<param-value>135</param-value>
        	</init-param>
        	
        	<init-param>
        		<param-name>kaptcha.textproducer.char.string</param-name>
        		<param-value>ACDEFHKPRSTWX345679</param-value>
        	</init-param>
        	
        	<init-param>
        		<param-name>kaptcha.image.height</param-name>
        		<param-value>50</param-value>
        	</init-param>
        	
        	<init-param>
        		<param-name>kaptcha.textproducer.font.size</param-name>
        		<param-value>43</param-value>
        	</init-param>
        	
        	<init-param>
        		<param-name>kaptcha.noise.color</param-name>
        		<param-value>black</param-value>
        	</init-param>
        	
        	<init-param>
        		<param-name>kaptcha.textproducer.char.length</param-name>
        		<param-value>4</param-value>
        	</init-param>
        	
        	<init-param>
        		<param-name>kaptcha.textproducer.font.names</param-name>
        		<param-value>Arial</param-value>
        	</init-param>
        </servlet>
        
        
        <servlet-mapping>
        	<servlet-name>Kaptcha</servlet-name>
        	<url-pattern>/Kaptcha</url-pattern>
        </servlet-mapping>
        
        <servlet>
        	<servlet-name>spring-dispatcher</servlet-name>
        	<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        	<init-param>
        		<param-name>contextConfigLocation</param-name>
        		<param-value>classpath:spring/spring-*.xml</param-value>
        	</init-param>
        </servlet>
    	<servlet-mapping>
    		<servlet-name>spring-dispatcher</servlet-name>
    		
    		<url-pattern>/</url-pattern>
    	</servlet-mapping>
    </web-app>

第三步：在html中绑值

<li>
    	<div class="item-content">
    		<div class="item-inner">
    			<div class="item-title label">验证码</div>
    				<input type="text" id="j_captcha" placeholder="验证码">
    						<div class="item-input">
    
        <img id="captcha_img" alt="点击更换" title="点击更换" onclick="changeVerifyCode(this)" src="../Kaptcha" />
    
    			</div>
    		</div>
    	</div>
    </li>

第四步：编写验证码请求方法，并将js文件引入html**底部**

// 获取验证码
    function changeVerifyCode(img){
    	img.src = "../Kaptcha?" + Math.floor(Math.random() * 100);
    }

判断验证码和用户输入的验证码是否相同工具类

import javax.servlet.http.HttpServletRequest;
    
    public class CodeUtil {
    	// 判断验证码是否符和预期的
    	public static boolean checkVerifyCode(HttpServletRequest request){
    		// 获取实际的验证码
    		String verifyCodeExpected = (String) request.getSession().getAttribute(
    				com.google.code.kaptcha.Constants.KAPTCHA_SESSION_KEY);
    		
    		// 获取用户输入的验证码
    		String verifyCodeActual = HttpServletRequestUtil.getString(request, "verifyCodeActual");
    		if(verifyCodeActual == null || !verifyCodeActual.equals(verifyCodeExpected)){
    			return false;
    		}
    		return true;		
    	}
    	
    }