Java 图形验证码

简介

Java 图形验证码，支持 Gif、中文、算术等类型，可用于 Java Web、JavaSE 等项目。

效果展

集成项目

• maven 方式引入：

<dependency>
       <groupId>com.github.whvcse</groupId>
       <artifactId>easy-captcha</artifactId>
       <version>1.6.2</version>
</dependency>

• 在 SpringBoot 中使用

package com.hikvision.websocketparent.controller;

import com.wf.captcha.utils.CaptchaUtil;
import org.springframework.web.bind.annotation.*;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * @author dongliang7
 * @projectName
 * @ClassName CaptchaController.java
 * @description: 图形验证码控制层
 * @createTime 2022年12月28日 12:30:00
 */
@RestController
@RequestMapping("/captcha")
public class CaptchaController {

    /**
     * 获取验证码
     * @param request
     * @param response
     * @throws IOException
     */
    @GetMapping("/getCaptcha")
    public void captcha(HttpServletRequest request, HttpServletResponse response) throws IOException {
        CaptchaUtil.out(request, response);
    }

    /**
     * 验证码校验
     * @param verCode
     * @param request
     * @return
     */
    @GetMapping("/verification")
    public String verification(@RequestParam String verCode, HttpServletRequest request){
        if (!CaptchaUtil.ver(verCode, request)) {
            CaptchaUtil.clear(request);  // 清除session中的验证码
            return "验证码不正确";
        }
        return "验证码验证成功";
    }
}

• 图片验证码公用类如果想改造，可以自行实现CaptchaUtil

package com.wf.captcha.utils;

import java.awt.*;
import java.io.IOException;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import com.wf.captcha.base.Captcha;
import com.wf.captcha.SpecCaptcha;

/**
 * 图形验证码工具类
 * Created by 王帆 on 2018-07-27 上午 10:08.
 */
public class CaptchaUtil {
    private static final String SESSION_KEY = "captcha";
    private static final int DEFAULT_LEN = 4;  // 默认长度
    private static final int DEFAULT_WIDTH = 130;  // 默认宽度
    private static final int DEFAULT_HEIGHT = 48;  // 默认高度

    /**
     * 输出验证码
     *
     * @param request  HttpServletRequest
     * @param response HttpServletResponse
     * @throws IOException IO异常
     */
    public static void out(HttpServletRequest request, HttpServletResponse response)
            throws IOException {
        out(DEFAULT_LEN, request, response);
    }

    /**
     * 输出验证码
     *
     * @param len      长度
     * @param request  HttpServletRequest
     * @param response HttpServletResponse
     * @throws IOException IO异常
     */
    public static void out(int len, HttpServletRequest request, HttpServletResponse response)
            throws IOException {
        out(DEFAULT_WIDTH, DEFAULT_HEIGHT, len, request, response);
    }

    /**
     * 输出验证码
     *
     * @param width    宽度
     * @param height   高度
     * @param len      长度
     * @param request  HttpServletRequest
     * @param response HttpServletResponse
     * @throws IOException IO异常
     */
    public static void out(int width, int height, int len, HttpServletRequest request, HttpServletResponse response)
            throws IOException {
        out(width, height, len, null, request, response);
    }

    /**
     * 输出验证码
     *
     * @param font     字体
     * @param request  HttpServletRequest
     * @param response HttpServletResponse
     * @throws IOException IO异常
     */
    public static void out(Font font, HttpServletRequest request, HttpServletResponse response)
            throws IOException {
        out(DEFAULT_WIDTH, DEFAULT_HEIGHT, DEFAULT_LEN, font, request, response);
    }

    /**
     * 输出验证码
     *
     * @param len      长度
     * @param font     字体
     * @param request  HttpServletRequest
     * @param response HttpServletResponse
     * @throws IOException IO异常
     */
    public static void out(int len, Font font, HttpServletRequest request, HttpServletResponse response)
            throws IOException {
        out(DEFAULT_WIDTH, DEFAULT_HEIGHT, len, font, request, response);
    }

    /**
     * 输出验证码
     *
     * @param width    宽度
     * @param height   高度
     * @param len      长度
     * @param font     字体
     * @param request  HttpServletRequest
     * @param response HttpServletResponse
     * @throws IOException IO异常
     */
    public static void out(int width, int height, int len, Font font, HttpServletRequest request, HttpServletResponse response)
            throws IOException {
        SpecCaptcha specCaptcha = new SpecCaptcha(width, height, len);
        if (font != null) {
            specCaptcha.setFont(font);
        }
        out(specCaptcha, request, response);
    }


    /**
     * 输出验证码
     *
     * @param captcha  Captcha
     * @param request  HttpServletRequest
     * @param response HttpServletResponse
     * @throws IOException IO异常
     */
    public static void out(Captcha captcha, HttpServletRequest request, HttpServletResponse response)
            throws IOException {
        setHeader(response);
        request.getSession().setAttribute(SESSION_KEY, captcha.text().toLowerCase());
        captcha.out(response.getOutputStream());
    }

    /**
     * 验证验证码
     *
     * @param code    用户输入的验证码
     * @param request HttpServletRequest
     * @return 是否正确
     */
    public static boolean ver(String code, HttpServletRequest request) {
        if (code != null) {
            String captcha = (String) request.getSession().getAttribute(SESSION_KEY);
            return code.trim().toLowerCase().equals(captcha);
        }
        return false;
    }

    /**
     * 清除session中的验证码
     *
     * @param request HttpServletRequest
     */
    public static void clear(HttpServletRequest request) {
        request.getSession().removeAttribute(SESSION_KEY);
    }

    /**
     * 设置相应头
     *
     * @param response HttpServletResponse
     */
    public static void setHeader(HttpServletResponse response) {
        response.setContentType("image/gif");
        response.setHeader("Pragma", "No-cache");
        response.setHeader("Cache-Control", "no-cache");
        response.setDateHeader("Expires", 0);
    }

}

源码：https://gitee.com/whvse/EasyCaptcha