验证码生成

验证码

验证码随机生成

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

public class Code {
//    public static void main(String[] args) {
//        Scanner sc = new Scanner(System.in);
//        System.out.println("请输入需要生成的验证码长度");
//        int n = sc.nextInt();
//        System.out.println("验证码生成成功:"+Code.createCode(n));
//    }

    static String createCode(int n){

        // 定义随机数构造
        Random random = new Random();

        // 定义空字符串保存验证码
        String Code = "";

        // 定义一个for循环，表示生成n位验证码
        for (int i = 0; i < n; i++) {

            // 根据随机数选择各个位置的字符表示
            int r = random.nextInt(3);

            switch (r){
                // 大写字母，A 65 - Z 90  随机数 （0-25）+ 65
                case 0: char C = (char) (random.nextInt(26)+65);
                    Code += C;
                    break;
                // 小写字母，a 97 - z 122  随机数 （0-25）+ 97
                case 1:  char c = (char) (random.nextInt(26)+97);
                    Code += c;
                    break;
                // 数字字符，0-9
                case 2:  int x = random.nextInt(10);
                    Code += x;
                    break;
            }
        }
        return Code;
    }

    static void DrawCode(String code) throws IOException {

        //构造BufferedImage图像对象
        //宽像素，高像素，色彩空间类型

        BufferedImage image = new BufferedImage(80, 32, BufferedImage.TYPE_BYTE_BINARY);

        //编辑图像
        //获取绘图对象
        Graphics g = image.getGraphics();

        //设置字体颜色
        g.setColor(Color.white);

        //设置字体
        g.setFont(new Font("SimSong", Font.ITALIC, 20));

        //字符串输出内容，水平起始坐标，垂直起始坐标
        g.drawString(code, 17, 24);

        //输出图像
        System.out.println("验证码生成"
                + (ImageIO.write(image, "png", new FileOutputStream("/Users/ray/code.png")) ? "成功" : "失败")
                + "："
                + code);
    }
}

验证过程

import java.io.IOException;
import java.util.Objects;
import java.util.Scanner;

public class CodeTest {

    static final String Tips = "请输入验证码|输入 - 更换验证码";
    static final int n = 4;

    public static void main(String[] args) throws IOException {

        String code = Code.createCode(n);
        Code.DrawCode(code);
        Scanner sc = new Scanner(System.in);
        System.out.println(Tips);
        String userCode = sc.next();
        for (int i = 0; i < 3; i++) {
            if(Objects.equals(userCode,"-")){
                code = Code.createCode(n);
                Code.DrawCode(code);
                System.out.println(Tips);
                userCode = sc.next();
            }
        }
        if(userCode.equalsIgnoreCase(code)) { // 忽略大小写 判断
            System.out.println("验证成功");
        } else {
            System.out.println("验证失败,请重新输入！");
        }
    }
}