分享一個生成驗證碼的java例項
阿新 • • 發佈：2018-12-03
直接上程式碼：
1 import javax.imageio.ImageIO; 2 import java.awt.*; 3 import java.awt.image.BufferedImage; 4 import java.io.IOException; 5 import java.io.OutputStream; 6 import java.util.Random; 7 8 /** 9 * @author kabuqinuo 10 * @date 2018/7/4 13:25 11 */ 12 public class CreateImageCode {13 14 /** 15 * 圖片的寬度 16 */ 17 private int width = 160; 18 /** 19 * 圖片的高度 20 */ 21 private int height = 40; 22 /** 23 * 驗證碼字元個數 24 */ 25 private int codeCount = 4; 26 /** 27 * 驗證碼干擾線數 28 */ 29 private int lineCount = 20; 30/** 31 * 驗證碼 32 */ 33 private String code = null; 34 35 private BufferedImage buffImg = null; 36 Random random = new Random(); 37 38 public CreateImageCode() { 39 createImage(); 40 } 41 42 public CreateImageCode(int width, int height) { 43 this.width = width; 44 this.height = height; 45 createImage(); 46 } 47 48 public CreateImageCode(int width, int height, int codeCount) { 49 this.width = width; 50 this.height = height; 51 this.codeCount = codeCount; 52 createImage(); 53 } 54 55 public CreateImageCode(int width, int height, int codeCount, int lineCount) { 56 this.width = width; 57 this.height = height; 58 this.codeCount = codeCount; 59 this.lineCount = lineCount; 60 createImage(); 61 } 62 63 64 /** 65 * 生成圖片 66 */ 67 private void createImage() { 68 // 字型的寬度 69 int fontWidth = width / codeCount; 70 // 字型的高度 71 int fontHeight = height - 5; 72 int codeY = height - 8; 73 74 // 影象buffer 75 buffImg = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB); 76 Graphics g = buffImg.getGraphics(); 77 78 // 設定背景色 79 g.setColor(getRandColor(200, 250)); 80 g.fillRect(0, 0, width, height); 81 82 83 84 // 設定字型 85 //Font font1 = getFont(fontHeight); 86 Font font = new Font("Fixedsys", Font.BOLD, fontHeight); 87 g.setFont(font); 88 89 // 設定干擾線 90 for (int i = 0; i < lineCount; i++) { 91 int xs = random.nextInt(width); 92 int ys = random.nextInt(height); 93 int xe = xs + random.nextInt(width); 94 int ye = ys + random.nextInt(height); 95 g.setColor(getRandColor(1, 255)); 96 g.drawLine(xs, ys, xe, ye); 97 } 98 99 // 新增噪點 100 float yawpRate = 0.01f; 101 int area = (int) (yawpRate * width * height); 102 for (int i = 0; i < area; i++) { 103 int x = random.nextInt(width); 104 int y = random.nextInt(height); 105 106 buffImg.setRGB(x, y, random.nextInt(255)); 107 } 108 109 // 得到隨機字元 110 String str1 = randomStr(codeCount); 111 this.code = str1; 112 for (int i = 0; i < codeCount; i++) { 113 String strRand = str1.substring(i, i + 1); 114 g.setColor(getRandColor(1, 255)); 115 116 // a為要畫出來的東西，x和y表示要畫的東西最左側字元的基線位於此圖形上下文座標系的 (x, y) 位置處 117 g.drawString(strRand, i*fontWidth+3, codeY); 118 } 119 } 120 121 /** 122 * 得到隨機字串 123 * @param n 124 * @return 125 */ 126 private String randomStr(int n) { 127 String str1 = "ABCDEFGHJKMNOPQRSTUVWXYZabcdefghjkmnopqrstuvwxyz1234567890"; 128 String str2 = ""; 129 int len = str1.length() - 1; 130 double r; 131 for (int i = 0; i < n; i++) { 132 r = (Math.random()) * len; 133 str2 = str2 + str1.charAt((int) r); 134 } 135 return str2; 136 } 137 138 /** 139 * 得到隨機顏色 140 * @param fc 141 * @param bc 142 * @return 143 */ 144 private Color getRandColor(int fc, int bc) { 145 if (fc > 255){ 146 fc = 255; 147 } 148 if (bc > 255){ 149 bc = 255; 150 } 151 int r = fc + random.nextInt(bc - fc); 152 int g = fc + random.nextInt(bc - fc); 153 int b = fc + random.nextInt(bc - fc); 154 return new Color(r, g, b); 155 } 156 157 /** 158 * 產生隨機字型 159 */ 160 private Font getFont(int size) { 161 Random random = new Random(); 162 Font[] font = new Font[5]; 163 font[0] = new Font("Ravie", Font.PLAIN, size); 164 font[1] = new Font("Antique Olive Compact", Font.PLAIN, size); 165 font[2] = new Font("Fixedsys", Font.PLAIN, size); 166 font[3] = new Font("Wide Latin", Font.PLAIN, size); 167 font[4] = new Font("Gill Sans Ultra Bold", Font.PLAIN, size); 168 return font[random.nextInt(5)]; 169 } 170 171 /** 172 * 扭曲方法 173 * @param g 174 * @param w1 175 * @param h1 176 * @param color 177 */ 178 private void shear(Graphics g, int w1, int h1, Color color) { 179 shearX(g, w1, h1, color); 180 shearY(g, w1, h1, color); 181 } 182 183 private void shearX(Graphics g, int w1, int h1, Color color) { 184 185 int period = random.nextInt(2); 186 187 boolean borderGap = true; 188 int frames = 1; 189 int phase = random.nextInt(2); 190 191 for (int i = 0; i < h1; i++) { 192 double d = (double) (period >> 1) 193 * Math.sin((double) i / (double) period 194 + (6.2831853071795862D * (double) phase) 195 / (double) frames); 196 g.copyArea(0, i, w1, 1, (int) d, 0); 197 if (borderGap) { 198 g.setColor(color); 199 g.drawLine((int) d, i, 0, i); 200 g.drawLine((int) d + w1, i, w1, i); 201 } 202 } 203 204 } 205 206 private void shearY(Graphics g, int w1, int h1, Color color) { 207 208 int period = random.nextInt(40) + 10; 209 210 boolean borderGap = true; 211 int frames = 20; 212 int phase = 7; 213 for (int i = 0; i < w1; i++) { 214 double d = (double) (period >> 1) 215 * Math.sin((double) i / (double) period 216 + (6.2831853071795862D * (double) phase) 217 / (double) frames); 218 g.copyArea(i, 0, 1, h1, 0, (int) d); 219 if (borderGap) { 220 g.setColor(color); 221 g.drawLine(i, (int) d, i, 0); 222 g.drawLine(i, (int) d + h1, i, h1); 223 } 224 225 } 226 227 } 228 229 230 231 public void write(OutputStream sos) throws IOException { 232 ImageIO.write(buffImg, "png", sos); 233 sos.close(); 234 } 235 236 public BufferedImage getBuffImg() { 237 return buffImg; 238 } 239 240 public String getCode() { 241 return code.toLowerCase(); 242 } 243 }
然後是呼叫方法：
1 /*生成驗證碼*/ 2 @ApiOperation(value = "生成驗證碼", notes = "登入時生成的驗證碼") 3 @GetMapping(value = "/code") 4 public void Captcha(HttpServletResponse response, HttpSession session) throws IOException { 5 6 /*通知瀏覽器不要快取*/ 7 response.setHeader("Expires", "-1"); 8 response.setHeader("Cache-Control", "no-cache"); 9 response.setHeader("Pragma", "-1"); 10 CreateImageCode vCode = new CreateImageCode(116,36,5,10); 11 String code = vCode.getCode(); 12 session.setAttribute("code", code); 13 vCode.write(response.getOutputStream()); 14 }
最後是生成的驗證碼：
直接拿來用即可。