Spring mvc 部分代码
@RequestMapping(value = "/getAuthImg", method = RequestMethod.GET)
@ResponseBody
public void getAuthImg(HttpServletResponse response) throws IOException {
new AuthImg().service(response);
}
验证码生成代码 AuthImg.java ,将生成的验证码的码值放在了session中(这是shiro的部分代码,所以session获取是通过SecurityUtils.getSubject().getSession()得到的)
package com.util;
import javax.servlet.http.*;
import java.io.*;
import java.awt.*;
import java.awt.image.*;
import java.util.*;
import javax.imageio.*;
import org.apache.shiro.SecurityUtils;
public class AuthImg {
//设置字体
private final Font mFont = new Font("Arial Black", Font.PLAIN, 21);
private final int IMG_WIDTH = 75;
private final int IMG_HEIGTH = 36;
public void service( HttpServletResponse response) throws IOException {
response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0);
response.setContentType("image/jpeg");
BufferedImage image = new BufferedImage(IMG_WIDTH, IMG_HEIGTH, BufferedImage.TYPE_INT_RGB);
Graphics g = image.getGraphics();
Random random = new Random();
g.setColor(getRandColor(200, 250));
g.fillRect(1, 1, IMG_WIDTH - 1, IMG_HEIGTH - 1);
g.setColor(new Color(102, 102, 102));
g.drawRect(0, 0, IMG_WIDTH - 1, IMG_HEIGTH - 1);
g.setColor(getRandColor(160, 200));
for (int i = 0; i < 30; i++) {
int x = random.nextInt(IMG_WIDTH - 1);
int y = random.nextInt(IMG_HEIGTH - 1);
int xl = random.nextInt(6) + 1;
int yl = random.nextInt(12) + 1;
g.drawLine(x, y, x + xl, y + yl);
}
g.setColor(getRandColor(160, 200));
for (int i = 0; i < 30; i++) {
int x = random.nextInt(IMG_WIDTH - 1);
int y = random.nextInt(IMG_HEIGTH - 1);
int xl = random.nextInt(12) + 1;
int yl = random.nextInt(6) + 1;
g.drawLine(x, y, x - xl, y - yl);
}
g.setFont(mFont);
String sRand = "";
for (int i = 0; i < 4; i++) {
String tmp = getRandomChar();
sRand += tmp;
g.setColor(new Color(20 + random.nextInt(110), 20 + random.nextInt(110), 20 + random.nextInt(110)));
//设置字体位置
g.drawString(tmp, 15 * i + 11, 25);
}
SecurityUtils.getSubject().getSession().setAttribute("rand", sRand);
g.dispose();
ImageIO.write(image, "JPEG", response.getOutputStream());
}
private String getRandomChar() {
int rand = (int) Math.round(Math.random() * 2);
long itmp = 0;
char ctmp = '\u0000';
switch (rand) {
case 1:
itmp = Math.round(Math.random() * 25 + 65);
ctmp = (char) itmp;
return String.valueOf(ctmp);
case 2:
itmp = Math.round(Math.random() * 25 + 97);
ctmp = (char) itmp;
return String.valueOf(ctmp);
default:
itmp = Math.round(Math.random() * 9);
return itmp + "";
}
}
private Color getRandColor(int fc, int bc) {
Random random = new Random();
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);
}
}
显示部分
<img src="getAuthImg" id="AuthImg">
js动态修改部分,防止浏览器缓存,加入一个时间属性
$('#AuthImg').on('click', function() {
var timestamp = new Date().getTime();
$(this).attr("src", $("#AuthImg").attr('src') + '?' + timestamp);
});