java web后台生成随机数字字母验证码
生成验证码的工具类如下：
import java.awt.*;import java.awt.image.BufferedImage;import java.util.Random;public class CreateVerifiCodeImage {private static int WIDTH = 90;private static int HEIGHT = 35;private static int FONT_SIZE = 20; //字符大小private static char[] verifiCode; //验证码private static BufferedImage verifiCodeImage; //验证码图片/*** @description: 获取验证码图片* @param: no* @return: java.awt.image.BufferedImage*/public static BufferedImage getVerifiCodeImage() {verifiCodeImage = new BufferedImage(WIDTH, HEIGHT, BufferedImage.TYPE_INT_BGR);// create a imageGraphics graphics = verifiCodeImage.getGraphics();verifiCode = generateCheckCode();drawBackground(graphics);drawRands(graphics, verifiCode);graphics.dispose();return verifiCodeImage;}/*** @description: 获取验证码* @param: no* @return: char[]*/public static char[] getVerifiCode() {return verifiCode;}/*** @description: 随机生成验证码* @param: no* @return: char[]*/private static char[] generateCheckCode() {String chars = "0123456789abcdefghijklmnopqrstuvwxyz" + "ABCDEFGHIJKLMNOPQRSTUVWXYZ";char[] rands = new char[4];for (int i = 0; i < 4; i++) {int rand = (int) (Math.random() * (10 + 26 * 2));rands[i] = chars.charAt(rand);}return rands;}/*** @description: 绘制验证码* @param: g* @param: rands* @return: void*/private static void drawRands(Graphics g, char[] rands) {g.setFont(new Font("Console", Font.BOLD, FONT_SIZE));for (int i = 0; i < rands.length; i++) {g.setColor(getRandomColor());g.drawString("" + rands[i], i * FONT_SIZE + 10, 25);}}/*** @description: 绘制验证码图片背景* @param: g* @return: void*/private static void drawBackground(Graphics g) {g.setColor(Color.white);g.fillRect(0, 0, WIDTH, HEIGHT);// 绘制验证码干扰点for (int i = 0; i < 200; i++) {int x = (int) (Math.random() * WIDTH);int y = (int) (Math.random() * HEIGHT);g.setColor(getRandomColor());g.drawOval(x, y, 1, 1);}}/*** @description: 获取随机颜色* @param: no* @return: java.awt.Color*/private static Color getRandomColor() {Random ran = new Random();return new Color(ran.nextInt(220), ran.nextInt(220), ran.nextInt(220));}}
controller接口调用及将验证码放入session
@ApiOperation("获取验证码图片")@GetMapping("/getVerifiCodeImage")public void getVerifiCodeImage(HttpServletRequest request, HttpServletResponse response) {// 获取图片BufferedImage verifiCodeImage = CreateVerifiCodeImage.getVerifiCodeImage();// 获取图片上的验证码String verifiCode = new String(CreateVerifiCodeImage.getVerifiCode());// 将验证码文本放入session域,为下一次验证做准备HttpSession session = request.getSession();session.setAttribute("verifiCode", verifiCode);// 将验证码图片响应给浏览器try {ImageIO.write(verifiCodeImage, "JPEG", response.getOutputStream());} catch (IOException e) {e.printStackTrace();}}
