两个数字之和的验证码

Question

如何用两个数字之和编写验证码？示例：1+4 （请完整回答这个问题，我对验证码一无所知！）

Answer 1

验证码的目的是将真实的、活生生的人类与自动化软件区分开来。

所以验证码要求人们做人擅长的事情，但机器不是。一旦机器有能力做某事，验证码就必须改变并做其他事情。简单的文本不再起作用，因为 OCR 已经足够好，可以自动读取它 - 因此，您现在经常看到的扭曲文本。在不久的将来可能会被其他内容取代，例如“这张图片中显示的是什么类型的东西”等。

计算机的任务越简单，它就越不适合验证码。

添加两个数字对于验证码不是一个好主意；事实上，它的有效性可能低于零。

请再次检查您想要做什么以及为什么。如果您想编写自己的验证码而不是使用已有的验证码，请在实施之前先考虑一下。

也许使用ReCAPTCHA 或something similar 是更好的方法？

Answer 2

CAPTCHA is an acronym for:

Completely    
Automated    
Public    
Turing-test to tell    
Computers and    
Humans    
Apart

创建验证码是为了阻止自动计算机垃圾邮件机器人填写表格、收集电子邮件地址，然后发送无数垃圾邮件。

Answer 3

您需要使用以下jar文件：

<dependency>
    <groupId>cn.apiclub.tool</groupId>
    <artifactId>simplecaptcha</artifactId>
    <version>1.2.2</version>
</dependency>

那你需要扩展接口类TextProducer

package com.java.captcha;

import java.util.Random;

import cn.apiclub.captcha.text.producer.TextProducer;

public class MyTextProducer implements TextProducer {
    private int answer;

    @Override
    public String getText() {
        Random random = new Random();
        int random1 = random.nextInt(90)+10;
        int random2 = random.nextInt(90)+10;
        int sum = random1 + random2;
        this.setAnswer(sum);
        StringBuffer captchaStringBuffer = new StringBuffer();
        captchaStringBuffer.append(random1 + "+" + random2 + "=" + "?");
        return captchaStringBuffer.toString();
    }

    public int getAnswer() {
        return answer;
    }

    public void setAnswer(int answer) {
        this.answer = answer;
    }

}

您需要创建实现 Serializable 接口的类 CaptchaDetails

package com.java.captcha;

import java.io.Serializable;

import javax.servlet.http.HttpServletRequest;

import org.springframework.web.util.WebUtils;

import cn.apiclub.captcha.Captcha;

public class CaptchaDetails implements Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = -4326389569050611057L;
    private final Captcha captcha;
    
    public CaptchaDetails(HttpServletRequest request){
    this.captcha=(Captcha) WebUtils.getSessionAttribute(request, "captcha");
    }

    public Captcha getCaptcha() {
        return captcha;
    }
}

You need to create class CaptchaGenerator which implements InitializingBean interface



 package com.java.captcha;
    
    import org.springframework.beans.factory.InitializingBean;
    
    import cn.apiclub.captcha.Captcha;
    import cn.apiclub.captcha.backgrounds.BackgroundProducer;
    import cn.apiclub.captcha.backgrounds.TransparentBackgroundProducer;
    import cn.apiclub.captcha.noise.CurvedLineNoiseProducer;
    import cn.apiclub.captcha.noise.NoiseProducer;
    import cn.apiclub.captcha.text.producer.DefaultTextProducer;
    import cn.apiclub.captcha.text.producer.TextProducer;
    import cn.apiclub.captcha.text.renderer.DefaultWordRenderer;
    import cn.apiclub.captcha.text.renderer.WordRenderer;
    
    public class CaptchaGenerator implements InitializingBean {
        
        private BackgroundProducer backgroundProducer=new TransparentBackgroundProducer();
        private TextProducer textProducer=new MyTextProducer();
        private WordRenderer wordRenderer= new DefaultWordRenderer();
        private NoiseProducer noiseProducer=new CurvedLineNoiseProducer();
        
        public Captcha createCaptcha(int width, int height){
            return new Captcha.Builder(width, height)
                    .addBackground(backgroundProducer)
                    .addText(textProducer,wordRenderer)
                    .addNoise(noiseProducer).build();
        }
    
        @Override
        public void afterPropertiesSet() throws Exception {
            if(this.backgroundProducer==null){
                this.backgroundProducer=new TransparentBackgroundProducer();
            }
            if(this.textProducer==null){
                this.textProducer=new DefaultTextProducer();
            }
            if(this.wordRenderer==null){
                this.wordRenderer= new DefaultWordRenderer();
            }
            if(this.noiseProducer==null){
                this.noiseProducer=new CurvedLineNoiseProducer();
            }
    
        }
    
    }

你需要创建类 CaptchaUtils

package com.java.captcha;

import java.io.ByteArrayOutputStream;
import java.io.IOException;

import javax.imageio.ImageIO;
import javax.xml.bind.DatatypeConverter;

import cn.apiclub.captcha.Captcha;

public abstract class CaptchaUtils {
    public static String encodeBase64(Captcha captcha){
        try {
            ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
            ImageIO.write(captcha.getImage(), "png", outputStream);
            return DatatypeConverter.printBase64Binary(outputStream.toByteArray());
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
        return null;
    }
}

您需要将@Bean 属性添加到包含@SpringBootApplication 注解的springboot 类中

@Bean
    public CaptchaGenerator getCaptchaGenerator(){
        return new CaptchaGenerator();
    }

现在您可以在 dataProvider 中编写以下代码

package com.excelUpload.excelToOracle;

import java.util.HashMap;
import java.util.Map;
import static com.java.baseutil.ApplicationConatants.SUCCESS;
import javax.servlet.http.HttpSession;

import com.java.captcha.CaptchaGenerator;
import com.java.captcha.CaptchaUtils;

import cn.apiclub.captcha.Captcha;
import oracle.jdbc.logging.annotations.Logging;

public class XYZDataprovider{


    public Map<String, ?> getData(String dpMethod, HttpSession session, Map<?, ?> allRequestParams, Object masterData,
            ServiceProvider serviceProvider, Logging logging) {
        Map<String, Object>responseHashMap = new HashMap<String,Object>();
        Map<String,Object>dataHashMap = new HashMap<String,Object>();
        if(dpMethod.equals("getCaptchaDet")){
        try {
                        CaptchaGenerator captchaGenerator = new CaptchaGenerator();
                        Captcha captcha = captchaGenerator.createCaptcha(200, 50);
                        String str1="data:image/jpeg;base64,"+CaptchaUtils.encodeBase64(captcha);
                        dataHashMap.put("captchaAns", captchaGenerator.getTextProducer().getAnswer());
                        dataHashMap.put("captchaCode", str1);
                        responseHashMap.put("responseData", dataHashMap);
                        responseHashMap.put(SUCCESS, true);
                    } catch (Exception e) {
                            e.printStackTrace();      
                    }
        }
        return responseHashMap;
    }
}