1. Effect diagram
Second, the latter is the use of SpringBoot.
https://download.csdn.net/download/qq_36135928/10379447Click to open the link
3. Core code
public class VerificationImageUtils {
//Use the Algerian font. If there is no font in the system, you need to install the font. The font only displays uppercase, and the 1, 0, i, o characters that are easy to be confused are removed.
public static final String VERIFY_CODES = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ";
private static Random random = new Random();
/**
* Use the system default character source to generate verification code
* @param verifySize verification code length
* @return
*/
public static String generateVerifyCode(int verifySize){
return generateVerifyCode(verifySize, VERIFY_CODES);
}
/**
* Generate verification code using specified source
* @param verifySize verification code length
* @param sources verification code character source
* @return
*/
public static String generateVerifyCode(int verifySize, String sources){
if(sources == null || sources.length() == 0){
sources = VERIFY_CODES;
}
int codesLen = sources.length();
Random rand = new Random(System.currentTimeMillis());
StringBuilder verifyCode = new StringBuilder(verifySize);
for(int i = 0; i < verifySize; i++){
verifyCode.append(sources.charAt(rand.nextInt(codesLen-1)));
}
return verifyCode.toString();
}
/**
* Generate a random verification code file and return the verification code value
* @param w
* @param h
* @param outputFile
* @param verifySize
* @return
* @throws IOException
*/
public static String outputVerifyImage(int w, int h, File outputFile, int verifySize) throws IOException {
String verifyCode = generateVerifyCode(verifySize);
outputImage(w, h, outputFile, verifyCode);
return verifyCode;
}
/**
* Output random captcha image stream and return captcha value
* @param w
* @param h
* @param os
* @param verifySize
* @return
* @throws IOException
*/
public static String outputVerifyImage(int w, int h, OutputStream os, int verifySize) throws IOException{
String verifyCode = generateVerifyCode(verifySize);
outputImage(w, h, os, verifyCode);
return verifyCode;
}
/**
* Generate the specified verification code image file
* @param w
* @param h
* @param outputFile
* @param code
* @throws IOException
*/
public static void outputImage(int w, int h, File outputFile, String code) throws IOException{
if(outputFile == null){
return;
}
File dir = outputFile.getParentFile();
if(!dir.exists()){
dir.mkdirs();
}
try{
outputFile.createNewFile();
FileOutputStream fos = new FileOutputStream(outputFile);
outputImage(w, h, fos, code);
fos.close();
} catch(IOException e){
throw e;
}
}
/**
* Output the specified verification code image stream
* @param w
* @param h
* @param os
* @param code
* @throws IOException
*/
public static void outputImage(int w, int h, OutputStream os, String code) throws IOException{
int verifySize = code.length();
BufferedImage image = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Random rand = new Random();
Graphics2D g2 = image.createGraphics();
g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,RenderingHints.VALUE_ANTIALIAS_ON);
Color[] colors = new Color[5];
Color[] colorSpaces = new Color[] { Color.WHITE, Color.CYAN,
Color.GRAY, Color.LIGHT_GRAY, Color.MAGENTA, Color.ORANGE,
Color.PINK, Color.YELLOW };
float[] fractions = new float[colors.length];
for(int i = 0; i < colors.length; i++){
colors[i] = colorSpaces[rand.nextInt(colorSpaces.length)];
fractions[i] = rand.nextFloat();
}
Arrays.sort(fractions);
g2.setColor(Color.GRAY);// Set the border color
g2.fillRect(0, 0, w, h);
Color c = getRandColor(200, 250);
g2.setColor(c);// Set the background color
g2.fillRect(0, 2, w, h-4);
// draw interference lines
Random random = new Random();
g2.setColor(getRandColor(160, 200));// Set the color of the line
for (int i = 0; i < 20; i++) {
int x = random.nextInt(w - 1);
int y = random.nextInt(h - 1);
int xl = random.nextInt(6) + 1;
int yl = random.nextInt(12) + 1;
g2.drawLine(x, y, x + xl + 40, y + yl + 20);
}
// add noise
float yawpRate = 0.05f;// noise rate
int area = (int) (yawpRate * w * h);
for (int i = 0; i < area; i++) {
int x = random.nextInt(w);
int y = random.nextInt(h);
int rgb = getRandomIntColor();
image.setRGB(x, y, rgb);
}
shear(g2, w, h, c);// distort the picture
g2.setColor(getRandColor(100, 160));
int fontSize = h-4;
Font font = new Font("Algerian", Font.ITALIC, fontSize);
g2.setFont(font);
char[] chars = code.toCharArray();
for(int i = 0; i < verifySize; i++){
AffineTransform affine = new AffineTransform();
affine.setToRotation(Math.PI / 4 * rand.nextDouble() * (rand.nextBoolean() ? 1 : -1), (w / verifySize) * i + fontSize/2, h/2);
g2.setTransform (affine);
g2.drawChars(chars, i, 1, ((w-10) / verifySize) * i + 5, h/2 + fontSize/2 - 10);
}
g2.dispose();
ImageIO.write(image, "jpg", os);
}
private static Color getRandColor(int fc, int bc) {
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);
}
private static int getRandomIntColor() {
int[] rgb = getRandomRgb();
int color = 0;
for (int c : rgb) {
color = color << 8;
color = color | c;
}
return color;
}
private static int[] getRandomRgb() {
int[] rgb = new int[3];
for (int i = 0; i < 3; i++) {
rgb[i] = random.nextInt(255);
}
return rgb;
}
private static void shear(Graphics g, int w1, int h1, Color color) {
shearX(g, w1, h1, color);
shearY(g, w1, h1, color);
}
private static 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 static 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 static void main(String[] args) throws IOException{
// File dir = new File("F:/verifies");
// int w = 200, h = 80;
// for(int i = 0; i < 50; i++){
// String verifyCode = generateVerifyCode(4);
// File file = new File(dir, verifyCode + ".jpg");
// outputImage(w, h, file, verifyCode);
// }
// }
}
@RestController
@RequestMapping("/captchaImage")
public class CaptchaImageController {
/**
* Generate verification code
*
* @param request
* @param response
* @param model
* @throws ServletException
* @throws IOException
*/
@RequestMapping(value = "/kaptcha", method = RequestMethod.GET)
public void ImageCaptcha(HttpServletRequest request, HttpServletResponse response, Model model)
throws ServletException, IOException {
try {
// get the session id that will identify the generated captcha.
// the same id must be used to validate the response, the session id
// is a good candidate!
response.setHeader("Cache-Control", "no-store");
response.setHeader("Pragma", "no-cache");
response.setDateHeader("Expires", 0);
response.setContentType("image/jpeg");
String verifyCode = VerificationImageUtils.generateVerifyCode(4);
//save session session
HttpSession session = request.getSession(true);
session.setAttribute("verificationImage", verifyCode.toLowerCase());
//generate image
int w = 200, h = 80;
VerificationImageUtils.outputImage(w, h, response.getOutputStream(), verifyCode);
} catch (IllegalArgumentException e) {
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace ();
}
}
}
html
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="content-type" content="text/html; charset=UTF-8">
<meta charset="utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge,chrome=1" />
<meta name="renderer" content="webkit"/>
<meta name="format-detection" content="telephone=no,email=no"/>
<title>Verification Code</title>
<link rel="stylesheet" href="/css/login.css"/>
</head>
<body>
<div class="yzm">
<input type="text" name="" id="verifyCode" value="" placeholder="请输入验证码"/>
<img id="kaptcha" onClick="javascript:changeKaptcha();"
src="/captchaImage/kaptcha"/>
</div>
</body>
</html>
<script src="/js/jquery.js"></script>
<script type="text/javascript">
function changeKaptcha(){
$("#kaptcha").attr("src","/captchaImage/kaptcha?" + Math.floor(Math.random() * 100));
$("#verify").select();
}
</script>