给项目添加验证码的一种方式

女爷i 2022-06-16 02:59 207阅读 0赞

# 一.servlet类 #

import java.awt.image.BufferedImage;
    import java.io.ByteArrayOutputStream;
    import java.io.IOException;
    
    import javax.imageio.ImageIO;
    import javax.servlet.ServletException;
    import javax.servlet.ServletOutputStream;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import org.springframework.beans.factory.BeanFactoryUtils;
    import org.springframework.web.context.WebApplicationContext;
    import org.springframework.web.context.support.WebApplicationContextUtils;
    
    import cn.itcast.common.web.session.SessionProvider;
    
    import com.octo.captcha.service.CaptchaServiceException;
    import com.octo.captcha.service.image.ImageCaptchaService;
    
    /**
     * 提供验证码图片的Servlet
     */
    @SuppressWarnings("serial")
    public class JcaptchaServlet extends HttpServlet {
    	public static final String CAPTCHA_IMAGE_FORMAT = "jpeg";
    
    	private ImageCaptchaService captchaService;
    	private SessionProvider session;
    
    	@Override
    	public void init() throws ServletException {
    		WebApplicationContext appCtx = WebApplicationContextUtils
    				.getWebApplicationContext(getServletContext());
    		captchaService = (ImageCaptchaService) BeanFactoryUtils
    				.beanOfTypeIncludingAncestors(appCtx, ImageCaptchaService.class);
    		session = (SessionProvider) BeanFactoryUtils
    				.beanOfTypeIncludingAncestors(appCtx, SessionProvider.class);
    	}
    
    	@Override
    	protected void doGet(HttpServletRequest request,
    			HttpServletResponse response) throws ServletException, IOException {
    		byte[] captchaChallengeAsJpeg = null;
    		// the output stream to render the captcha image as jpeg into
    		ByteArrayOutputStream jpegOutputStream = new ByteArrayOutputStream();
    		try {
    			// 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 = session.getSessionId(request);
    			BufferedImage challenge = captchaService.getImageChallengeForID(
    					captchaId, request.getLocale());
    			// Jimi.putImage("image/jpeg", challenge, jpegOutputStream);
    			ImageIO.write(challenge, CAPTCHA_IMAGE_FORMAT, jpegOutputStream);
    		} catch (IllegalArgumentException e) {
    			response.sendError(HttpServletResponse.SC_NOT_FOUND);
    			return;
    		} catch (CaptchaServiceException e) {
    			response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
    			return;
    		}
    		// catch (JimiException e) {
    		// response.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
    		// return;
    		// }
    
    		captchaChallengeAsJpeg = jpegOutputStream.toByteArray();
    
    		// flush it in the response
    		response.setHeader("Cache-Control", "no-store");
    		response.setHeader("Pragma", "no-cache");
    		response.setDateHeader("Expires", 0);
    		response.setContentType("image/" + CAPTCHA_IMAGE_FORMAT);
    
    		ServletOutputStream responseOutputStream = response.getOutputStream();
    		responseOutputStream.write(captchaChallengeAsJpeg);
    		responseOutputStream.flush();
    		responseOutputStream.close();
    	}
    }

# 二.配置文件 #

## 1.captcha.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"
    	xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd"
    	default-lazy-init="true">
    
    	<bean id="captchaService" class="com.octo.captcha.service.multitype.GenericManageableCaptchaService">
    		<constructor-arg index="0" ref="imageEngine"/>
    		<constructor-arg type="int" index="1" value="180"/>
    		<constructor-arg type="int" index="2" value="100000"/>
    		<constructor-arg type="int" index="3" value="75000"/>
    	</bean>
    	<bean id="imageEngine" class="com.octo.captcha.engine.GenericCaptchaEngine">
    		<constructor-arg index="0">
    			<list>
    				<ref bean="captchaFactory"/>
    			</list>
    		</constructor-arg>
    	</bean>
    
    	<bean id="captchaFactory" class="com.octo.captcha.image.gimpy.GimpyFactory">
    		<constructor-arg>
    			<ref bean="wordgen"/>
    		</constructor-arg>
    		<constructor-arg>
    			<ref bean="wordtoimage"/>
    		</constructor-arg>
    	</bean>
    
    	<bean id="wordgen" class= "com.octo.captcha.component.word.wordgenerator.RandomWordGenerator">		
    		
    		<constructor-arg>
    			<value>aabbccddeefgghhkkmnnooppqqsstuuvvwxxyyzz</value>
    		</constructor-arg>
    	</bean>
    
    	<bean id="wordtoimage" class="com.octo.captcha.component.image.wordtoimage.ComposedWordToImage">
    		<constructor-arg index="0">
    			<ref bean="fontGenRandom"/>
    		</constructor-arg>
    		<constructor-arg index="1">
    			<ref bean="backGenUni"/>
    		</constructor-arg>
    		<constructor-arg index="2">
    			<ref bean="decoratedPaster"/>
    		</constructor-arg>
    	</bean>
    
    	<bean id="fontGenRandom" class="com.octo.captcha.component.image.fontgenerator.RandomFontGenerator">
    		
    		<constructor-arg index="0">
    			<value>26</value>
    		</constructor-arg>
    		
    		<constructor-arg index="1">
    			<value>34</value>
    		</constructor-arg>
    		<constructor-arg index="2">
    			<list>
    				<bean class="java.awt.Font">
    					<constructor-arg index="0"><value>Arial</value></constructor-arg>
    					<constructor-arg index="1"><value>0</value></constructor-arg>
    					<constructor-arg index="2"><value>32</value></constructor-arg>
    				</bean>
    			</list>
    		</constructor-arg>
    	</bean>
    	<bean id="backGenUni" class="com.octo.captcha.component.image.backgroundgenerator.UniColorBackgroundGenerator">
    		
    		<constructor-arg index="0">
    			<value>110</value>
    		</constructor-arg>
    		
    		<constructor-arg index="1">
    			<value>50</value>
    		</constructor-arg>
    	</bean>
    
    	<bean id="decoratedPaster" class="com.octo.captcha.component.image.textpaster.DecoratedRandomTextPaster">
    		
    		<constructor-arg type="java.lang.Integer" index="0">
    			<value>4</value>
    		</constructor-arg>
    		
    		<constructor-arg type="java.lang.Integer" index="1">
    			<value>4</value>
    		</constructor-arg>
    		
    		<constructor-arg index="2">
    			<ref bean="colorGen"/>
    		</constructor-arg>
    		
    		<constructor-arg index="3">
    			<list>
    				
    			</list>
    		</constructor-arg>
    	</bean>	
    	<bean id="baffleDecorator" class="com.octo.captcha.component.image.textpaster.textdecorator.BaffleTextDecorator">
    		<constructor-arg type="java.lang.Integer" index="0"><value>1</value></constructor-arg>
    		<constructor-arg type="java.awt.Color" index="1"><ref bean="colorWrite"/></constructor-arg>
    	</bean>
    	<bean id="colorGen" class="com.octo.captcha.component.image.color.SingleColorGenerator">
    		<constructor-arg type="java.awt.Color" index="0">
    			<ref bean="colorBlack"/>
    		</constructor-arg>
    	</bean>
    	<bean id="colorWrite" class="java.awt.Color">
    		<constructor-arg type="int" index="0">
    			<value>255</value>
    		</constructor-arg>
    		<constructor-arg type="int" index="1">
    			<value>255</value>
    		</constructor-arg>
    		<constructor-arg type="int" index="2">
    			<value>255</value>
    		</constructor-arg>
    	</bean>
    	<bean id="colorBlack" class="java.awt.Color">
    		<constructor-arg type="int" index="0">
    			<value>50</value>
    		</constructor-arg>
    		<constructor-arg type="int" index="1">
    			<value>50</value>
    		</constructor-arg>
    		<constructor-arg type="int" index="2">
    			<value>50</value>
    		</constructor-arg>
    	</bean>
    </beans>

## 2.web..xml ##

<servlet>
    		<servlet-name>captcha</servlet-name>
    		<servlet-class>cn.itcast.common.captcha.JcaptchaServlet</servlet-class>
    	</servlet>
    	<servlet-mapping>
    		<servlet-name>captcha</servlet-name>
    		<url-pattern>/captcha.svl</url-pattern>
    	</servlet-mapping>

# 三.jsp页面  #

<#if errorRemaining?? && errorRemaining<=0>
                        <tr>
                        	<td colspan="2" align="center"><img src="${base}/captcha.svl" οnclick="this.src='${base}/captcha.svl?d='+new Date()*1"/></td>
                        </tr>
                        <tr>
                          <td height="40" align="right"><strong><@s.m "login.captcha"/>ï¼</strong></td>
                          <td><input name="captcha" type="text" id="captcha" vld="{required:true}" class="input"/></td>
                        </tr>
                        </#if>