spring boot 实现用户登录认证

package sw.util; import javax.imageio.ImageIO; import java.awt.*; import java.awt.image.BufferedImage; import java.io.IOException; import java.io.OutputStream; import java.util.Random; /** * 验证码 * @author LR * */ public class Captcha { // 图片的宽度 private int width = 160; // 图片的高度。 private int height = 40; // 验证码字符个数 private int codeCount = 4; // 验证码干扰线数 private int lineCount = 20; // 验证码 private String code = null; // 验证码图片Buffer private BufferedImage image = null; Random random = new Random(); public Captcha() { generate(); } public Captcha(int width, int height) { this.width = width; this.height = height; generate(); } public Captcha(int width, int height, int codeCount) { this.width = width; this.height = height; this.codeCount = codeCount; generate(); } public Captcha(int width, int height, int codeCount, int lineCount) { this.width = width; this.height = height; this.codeCount = codeCount; this.lineCount = lineCount; generate(); } // 生成图片 private void generate() { int fontWidth = width / codeCount;// 字体的宽度 int fontHeight = height - 5;// 字体的高度 int codeY = height - 8; // 图像buffer image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); Graphics g = image.getGraphics(); //Graphics2D g = buffImg.createGraphics(); // 设置背景色 g.setColor(getRandColor(200, 250)); g.fillRect(0, 0, width, height); // 设置字体 //Font font1 = getFont(fontHeight); Font font = new Font("Fixedsys", Font.BOLD, fontHeight); g.setFont(font); // 设置干扰线 for (int i = 0; i < lineCount; i++) { int xs = random.nextInt(width); int ys = random.nextInt(height); int xe = xs + random.nextInt(width); int ye = ys + random.nextInt(height); g.setColor(getRandColor(1, 255)); g.drawLine(xs, ys, xe, ye); } // 添加噪点 float yawpRate = 0.01f;// 噪声率 int area = (int) (yawpRate * width * height); for (int i = 0; i < area; i++) { int x = random.nextInt(width); int y = random.nextInt(height); image.setRGB(x, y, random.nextInt(255)); } String str1 = randomStr(codeCount);// 得到随机字符 this.code = str1; for (int i = 0; i < codeCount; i++) { String strRand = str1.substring(i, i + 1); g.setColor(getRandColor(1, 255)); // g.drawString(a,x,y); // a为要画出来的东西，x和y表示要画的东西最左侧字符的基线位于此图形上下文坐标系的 (x, y) 位置处 g.drawString(strRand, i * fontWidth + 3, codeY); } } // 得到随机字符 private String randomStr(int n) { String str1 = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz1234567890"; String str2 = ""; int len = str1.length() - 1; double r; for (int i = 0; i < n; i++) { r = (Math.random()) * len; str2 = str2 + str1.charAt((int) r); } return str2; } // 得到随机颜色 private Color getRandColor(int fc, int bc) {// 给定范围获得随机颜色 if (fc > 255) fc = 255; if (bc > 255) bc = 255; int r = fc + random.nextInt(bc - fc); int g = fc + random.nextInt(bc - fc); int b = fc + random.nextInt(bc - fc); return new Color(r, g, b); } /** * 产生随机字体 */ private Font getFont(int size) { Random random = new Random(); Font font[] = new Font[5]; font[0] = new Font("Ravie", Font.PLAIN, size); font[1] = new Font("Antique Olive Compact", Font.PLAIN, size); font[2] = new Font("Fixedsys", Font.PLAIN, size); font[3] = new Font("Wide Latin", Font.PLAIN, size); font[4] = new Font("Gill Sans Ultra Bold", Font.PLAIN, size); return font[random.nextInt(5)]; } // 扭曲方法 private void shear(Graphics g, int w1, int h1, Color color) { shearX(g, w1, h1, color); shearY(g, w1, h1, color); } private void shearX(Graphics g, int w1, int h1, Color color) { int period = random.nextInt(2); boolean borderGap = true; int frames = 1; int phase = random.nextInt(2); for (int i = 0; i < h1; i++) { double d = (double) (period >> 1) * Math.sin((double) i / (double) period + (6.2831853071795862D * (double) phase) / (double) frames); g.copyArea(0, i, w1, 1, (int) d, 0); if (borderGap) { g.setColor(color); g.drawLine((int) d, i, 0, i); g.drawLine((int) d + w1, i, w1, i); } } } private void shearY(Graphics g, int w1, int h1, Color color) { int period = random.nextInt(40) + 10; // 50; boolean borderGap = true; int frames = 20; int phase = 7; for (int i = 0; i < w1; i++) { double d = (double) (period >> 1) * Math.sin((double) i / (double) period + (6.2831853071795862D * (double) phase) / (double) frames); g.copyArea(i, 0, 1, h1, 0, (int) d); if (borderGap) { g.setColor(color); g.drawLine(i, (int) d, i, 0); g.drawLine(i, (int) d + h1, i, h1); } } } public void write(OutputStream sos) throws IOException { ImageIO.write(image, "png", sos); sos.close(); } public BufferedImage getImage() { return image; } public String getCode() { return code.toLowerCase(); } }