原文：http://blog.csdn.net/huangshulang1234/article/details/51776806
@Action("/getCode1")
public void getCode1() throws IOException{
// TODO Auto-generated method stub
//设置不缓存图片
response.setHeader("Pragma", "No-cache");
response.setHeader("Cache-Control", "No-cache");
response.setDateHeader("Expires", 0);
//指定生成的响应图片
response.setContentType("image/jpeg");
int width=86; //指定生成验证码的宽度
int height=22; //指定生成验证码的高度
BufferedImage image = new BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics g = image.getGraphics();
Graphics2D g2d = (Graphics2D)g; //创建Graphics2D对象
Random random = new Random();
Font mFont = new Font("黑体", Font.BOLD, 16); //定义字体样式
g.setColor(getRandColor(200, 250));
g.fillRect(0, 0, width, height); //绘制背景
g.setFont(mFont); //设置字体
g.setColor(getRandColor(180, 200));
//绘制100根位置和颜色全部为随机产生的线条，该线条为2f
for (int i = 0; i < 100; i++) {
int x = random.nextInt(width-1);
int y = random.nextInt(height-1);
int x1 = random.nextInt(6)+1;
int y1 = random.nextInt(12)+1;
BasicStroke bs = new BasicStroke(2f,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL);
Line2D line = new Line2D.Double(x,y,x+x1,y+y1);
g2d.setStroke(bs);
g2d.draw(line); //绘制直线
}
//输出由英文，数字和中文随机组成的验证文字，具体的组合方式根据生成随机数确定
String sRand = "";
//输出随机的验证文字
String ctmp = "";
int itmp = 0;
for(int i = 0;i<4;i++){
//random = new Random(new java.util.Date().getTime()+i);
switch (random.nextInt(4)) {
case 1:
itmp = random.nextInt(26)+65; //生成A~Z的字母
ctmp = String.valueOf((char)itmp);
break;
case 2://生成汉字
String[] rBase = {"0","1","2","3","4","5","6","7","8","9","a","b","c","d","e","f"};
//生成第一位的区码
int r1 = random.nextInt(3)+11; //生成11~14之间的随机数
String str_r1 = rBase[r1];
//生成第二位的区码
int r2;
if(r1==13){
r2 = random.nextInt(7); //生成0~7之间的随数
}else{
r2 = random.nextInt(16); //生成0~16之间的随机数
}
String str_r2 = rBase[r2];
//生成第一位的位码
int r3 = random.nextInt(6)+10; //生成10~16之间的随机数
String str_r3 = rBase[r3];
//生成第二位的位码
int r4;
if(r3==10){
r4 = random.nextInt(15)+1; //生成1~16之间的随机数
}else if(r3==15){
r4 = random.nextInt(15); //生成0~15之间的随机数
}else {
r4 = random.nextInt(16); //生成0~16之间的随机数
}
String str_r4 = rBase[r4];
//将生成的机内码转换为汉字
byte[] bytes = new byte[2];
//将生成的区码保存到字节数组的第一个元素中
String str_r12 = str_r1+str_r2;
int tempLow=Integer.parseInt(str_r12,16);
bytes[0] = (byte)tempLow;
//将生成的位码保存到字节数组的第二个元素中
String str_r34 = str_r3+str_r4;
int tempHigh = Integer.parseInt(str_r34,16);
bytes[1] = (byte)tempHigh;
ctmp = new String(bytes); //根据字节数组生成汉字
break;
default:
itmp = random.nextInt(10)+48; //生成0~9的数字
ctmp = String.valueOf((char)itmp);
break;
}
sRand+=ctmp;
Color color = new Color(20+random.nextInt(110), 20+random.nextInt(110), 20+random.nextInt(110));
g.setColor(color);
//将生成的随机数进行随机缩放病旋转指定角度
//将文字旋转指定角度
Graphics2D g2d_word = (Graphics2D)g;
AffineTransform trans = new AffineTransform();
trans.rotate(random.nextInt(45)*3.14/180,15*i+8,7);
//缩放文字
float scaleSize = random.nextFloat()+0.8f;
if(scaleSize>1f){
scaleSize = 1f;
}
trans.scale(scaleSize, scaleSize);
g2d_word.setTransform(trans);
g.drawString(ctmp, 15*i+18, 14);
}
//将生成的验证码保存道session中
HttpSession session = request.getSession(true);
session.setAttribute("randCheckCode", sRand);
//输出生成的验证码图片
g.dispose();
ImageIO.write(image, "JPEG", response.getOutputStream());
}
public Color getRandColor(int s,int e){
Random random = new Random();
if(s>255)s = 255;
if(e>255)e = 255;
int r = s+random.nextInt(e-s);
int g = s+random.nextInt(e-s);
int b = s+random.nextInt(e-s);
return new Color(r, g, b);
}