验证码生成
根据传入的count值，生成count位的验证码
/*
* 验证码生成器
*/
@Controller
@RequestMapping("/tools/identiry")
public class IdentifyCodeController {
@RequestMapping("/code")
public void init(HttpServletRequest request, HttpServletResponse response){
//生成随机字符串，保存在SessionContext中，还可以保存在redis中
String random=RandomStringUtils.randomAlphanumeric(4);
SessionContext.setAttribute(request, SessionContext.IDENTIFY_CODE_KEY, random);
response.setContentType("image/jpeg");
response.addHeader("pragma", "NO-cache");
response.addHeader("Cache-Control","no-cache");
//浏览器不响应缓存
response.addDateHeader("Expries",0);
//将随机字符串显示在图像中，前端直接显示这里生成的带随机字符串的图像
int width=110, height=33;
//创建一个全新的BufferImage图像对象
//width表示图像的宽度，height表示图像的高度，最后一个参数表示图像字节灰度图像
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
//创建Graphics对象，用来获取画笔
Graphics g = image.getGraphics();
//以下填充背景色
g.setColor(new Color(225,225,225));
Font DeFont=new Font("SansSerif", Font.PLAIN, 26);
g.setFont(DeFont);
g.fillRect(0, 0, width, height);
//设置字体色
g.setColor(Color.BLACK);
//图像中要绘制的文本
g.drawString(random,20,25);
//graphics释放资源
g.dispose();
try {
ServletOutputStream outStream = response.getOutputStream();
//将JPG格式的BufferImage图像对象写入输出流
ImageIO.write(image, "JPG", outStream);
outStream.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
可直接生成random随机数，传入count值为4，start=0,end=0,letters=true，number=true,chars=null,random=new Random()
public static String random(int count, int start, int end, boolean letters, boolean numbers, char[] chars, Random random) {
if (count == 0) {
return "";
} else if (count < 0) {
throw new IllegalArgumentException("Requested random string length " + count + " is less than 0.");
} else {
if (start == 0 && end == 0) {
end = 123;
start = 32;
if (!letters && !numbers) {
start = 0;
end = 2147483647;
}
}
char[] buffer = new char[count];
int gap = end - start;
while(true) {
while(true) {
//根据count生成随机数，传入的count为4，则生成4个随机数
while(count-- != 0) {
char ch;
if (chars == null) {
ch = (char)(random.nextInt(gap) + start);
} else {
ch = chars[random.nextInt(gap) + start];
}
if (letters && Character.isLetter(ch) || numbers && Character.isDigit(ch) || !letters && !numbers) {
if (ch >= '\udc00' && ch <= '\udfff') {
if (count == 0) {
++count;
} else {
buffer[count] = ch;
--count;
buffer[count] = (char)('\ud800' + random.nextInt(128));
}
} else if (ch >= '\ud800' && ch <= '\udb7f') {
if (count == 0) {
++count;
} else {
buffer[count] = (char)('\udc00' + random.nextInt(128));
--count;
buffer[count] = ch;
}
} else if (ch >= '\udb80' && ch <= '\udbff') {
++count;
} else {
buffer[count] = ch;
}
} else {
++count;
}
}
return new String(buffer);
}
}
}
}
方法二：
也可根据当前时间生成随机验证码，同样是传入count值
//使用到Algerian字体，系统里没有的话需要安装字体，字体只显示大写，去掉了1,0,i,o几个容易混淆的字符
public static final String VERIFY_CODES = "23456789ABCDEFGHJKLMNPQRSTUVWXYZ";
private static Random random = new Random();
/**
* 使用指定源生成验证码
* @param verifySize 验证码长度
* @param sources 验证码字符源
* @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)));
}
System.out.println("java底层生成图形验证码字符：" + verifyCode.toString());
return verifyCode.toString();
}
直接显示验证码图像
/**
* 输出指定验证码图片流
* @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);// 设置边框色
g2.fillRect(0, 0, w, h);
Color c = getRandColor(200, 250);
g2.setColor(c);// 设置背景色
g2.fillRect(0, 2, w, h-4);
//绘制干扰线
Random random = new Random();
g2.setColor(getRandColor(160, 200));// 设置线条的颜色
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);
}
// 添加噪点
float yawpRate = 0.05f;// 噪声率
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);// 使图片扭曲
//g2.setColor(getRandColor(100, 160));
g2.setColor(new Color(197,54,12));
int fontSize = h-4;
//Font font = new Font("Algerian", Font.ITALIC, fontSize);
Font font = new Font("Cancun", Font.PLAIN, 22);
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);
}
前端页面直接调用后端接口，后端直接创建ImageIO对象，通过response.getOutputStream()输出流显示验证码：
<form id="registerForm" method="post" action="${s.base}/auth/doRegister.html" class="oc-form" style="text-align: center;border: 1px solid #CCC;width: 600px;margin:0 auto;padding:20px;" >
<li><label>用户名</label>
<input maxlength="20" id="username" name="username" type="text" class="input-text" placeholder="请输入用户名（英文数字）" >
</li>
<li><label>密码</label>
<input maxlength="20" id="password" name="password" type="password" class="input-text" placeholder="请输入密码" autocomplete="off" />
</li>
<li><label>验证码</label>
<input id="identiryCode" name="identiryCode" maxlength="6" class="input-text" type="text" style="width: 150px;" placeholder="请输入验证码"/>
<a class="vali-base"><img onclick="reloadIndityImg('indeityImgRegister');" id="indeityImgRegister" src="${s.base}/tools/identiry/code.html" style="width:80px;height:40px;float:left;margin-left:10px;"/></a>
</li>
<li id="errorMsg" class="clearfix" style="display: none;color:red;">用户名密码不能为空</li>
<li class="clearfix" style="margin-top: 30px;">
<input type="button" value="注册保存" class="btn" onclick="doSubmit();">
</li>
<li>
<a style="float: left;" href="${s.base}/auth/login.html">已有账号，去登录</a>
</li>
</form>
