package com.medical.study.utils;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.OutputStream;
import java.util.Random;

public class VerifyCode {
    //寬和高
    private int w = 85;
    private int h = 40;

    private Random r = new Random();
    // 定義有那些字體
    private String[] fontNames = { "宋體", "華文楷體", "黑體", "微軟雅黑", "楷體_GB2312" };
    // 定義有那些驗證碼的隨機字符
    private String codes = "23456789abcdefghjkmnopqrstuvwxyzABCDEFGHJKLMNOPQRSTUVWXYZ";
    // 生成背景色
    private Color bgColor = new Color(0, 255, 255);
    // 用于gettext 方法 獲得生成的驗證碼文本
    private String text;

    // 生成隨機顏色
    private Color randomColor() {
        int red = r.nextInt(255);
        int green = r.nextInt(255);
        int blue = r.nextInt(255);
        return new Color(red, green, blue);
    }

    // 生成隨機字體
    private Font randomFont() {
        int index = r.nextInt(fontNames.length);
        String fontName = fontNames[index];
        int style = r.nextInt(4);
        int size = r.nextInt(5) + 24;

        return new Font(fontName, style, size);
    }

    // 畫干擾線
    private void drawLine(BufferedImage image) {
        int num = 3;
        Graphics2D g2 = (Graphics2D) image.getGraphics();

        for (int i = 0; i < num; i++) {
            int x1 = r.nextInt(w);
            int y1 = r.nextInt(h);
            int x2 = r.nextInt(w);
            int y2 = r.nextInt(h);
            g2.setStroke(new BasicStroke(1.5F));// 不知道
            g2.setColor(Color.white);
            g2.drawLine(x1, y1, x2, y2);
        }
    }

    // 得到codes的長度內(nèi)的隨機數(shù) 并使用charAt 取得隨機數(shù)位置上的codes中的字符
    private char randomChar() {
        int index = r.nextInt(codes.length());
        return codes.charAt(index);
    }

    // 創(chuàng)建一張驗證碼的圖片
    public BufferedImage createImage() {
        BufferedImage image = new BufferedImage(w, h,
                BufferedImage.TYPE_INT_RGB);
        Graphics2D g2 = (Graphics2D) image.getGraphics();
        StringBuilder sb = new StringBuilder();
        // 向圖中畫四個字符
        for (int i = 0; i < 4; i++) {
            String s = randomChar() + "";
            sb.append(s);
            float x = i * 1.0F * w / 4;
            g2.setFont(randomFont());
            g2.setColor(randomColor());
            g2.drawString(s, x, h - 5);

        }
        this.text = sb.toString();
        drawLine(image);


        // 返回圖片
        return image;

    }

    // 得到驗證碼的文本 后面是用來和用戶輸入的驗證碼 檢測用
    public String getText() {
        return text;
    }

    // 定義輸出的對象和輸出的方向
    public static void output(BufferedImage bi, OutputStream fos)
            throws FileNotFoundException, IOException {
        ImageIO.write(bi, "JPEG", fos);
    }

}

package com.medical.study.controller;

import com.medical.study.utils.VerifyCode;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.concurrent.TimeUnit;

/**
 * 隨機4位數(shù)的驗證碼
 */

@RestController
@CrossOrigin
@RequestMapping("/code")
public class VerifyController {

    @Autowired
    private RedisTemplate redisTemplate;

    @RequestMapping("/verify")
    public void Verify(HttpServletRequest request, HttpServletResponse response) throws IOException {
                VerifyCode code = new VerifyCode();
        BufferedImage image = code.createImage();

        //驗證碼
        System.err.println(code.getText());

        //保存驗證碼到Redis,一分鐘有效期
        redisTemplate.opsForValue().set("verify:"+code.getText(),code.getText(),1L, TimeUnit.MINUTES);

        //驗證碼圖片格式
        ImageIO.write(image,"jpg",response.getOutputStream());


    }


}

<img :src="verifySrc" alt="圖片無法加載" @click="changeVerify()" >

//驗證碼
	const verifySrc=ref("http://localhost:8081/code/verify");
	function changeVerify(){
		verifySrc.value="http://localhost:8081/code/verify?"+new Date().getTime()
		
	}