Java版纯字母、纯数字、字母数字组合验证码的生成 (二)

2014-11-24 09:56:15 · 作者: · 浏览: 5
;//输出图片方法
} catch (Exception e) {
e.printStackTrace();
}
}
}
下面就是验证码生成的主要类了

[java]
public class RandomValidateCode {
public static final String RANDOMCODEKEY = "RANDOMVALIDATECODEKEY";// 放到session中的key
private Random random = new Random();
// 随机产生数字与字母组合的字符串
private String randString = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
/*
* private String randString = "0123456789";//随机产生只有数字的字符串 private String
* randString = "ABCDEFGHIJKLMNOPQRSTUVWXYZ";//随机产生只有字母的字符串
*/
private int width = 80;// 图片宽
private int height = 26;// 图片高
private int lineSize = 40;// 干扰线数量
private int stringNum = 4;// 随机产生字符数量

/*
* 获得字体
*/
private Font getFont() {
return new Font("Fixedsys", Font.CENTER_BASELINE, 18);
}

/*
* 获得颜色
*/
private Color getRandColor(int fc, int bc) {
if (fc > 255)
fc = 255;
if (bc > 255)
bc = 255;
int r = fc + random.nextInt(bc - fc - 16);
int g = fc + random.nextInt(bc - fc - 14);
int b = fc + random.nextInt(bc - fc - 18);
return new Color(r, g, b);
}

/**
* 生成随机图片
*/
public void getRandcode(HttpServletRequest request,
HttpServletResponse response) {
HttpSession session = request.getSession();
// BufferedImage类是具有缓冲区的Image类,Image类是用于描述图像信息的类
BufferedImage image = new BufferedImage(width, height,
BufferedImage.TYPE_INT_BGR);
Graphics g = image.getGraphics();// 产生Image对象的Graphics对象,改对象可以在图像上进行各种绘制操作
g.fillRect(0, 0, width, height);
g.setFont(new Font("Times New Roman", Font.ROMAN_BASELINE, 18));
g.setColor(getRandColor(110, 133));

// 绘制干扰线
for (int i = 0; i <= lineSize; i++) {
drowLine(g);
}
// 绘制随机字符
String randomString = "";
for (int i = 1; i <= stringNum; i++) {
randomString = drowString(g, randomString, i);
}
//将生成的随机字符串保存到session中,而jsp界面通过session.getAttribute("RANDOMCODEKEY"),
//获得生成的验证码,然后跟用户输入的进行比较
session.removeAttribute(RANDOMCODEKEY);
session.setAttribute(RANDOMCODEKEY, randomString);
g.dispose();
try {
// 将内存中的图片通过流动形式输出到客户端
ImageIO.write(image, "JPEG", response.getOutputStream());
} catch (Exception e) {
e.printStackTrace();
}

}

/*
* 绘制字符串
*/
private String drowString(Graphics g, String randomString, int i) {
g.setFont(getFont());
g.setColor(new Color(random.nextInt(101), random.nextInt(111), random
.nextInt(121)));
String rand = String.valueOf(getRandomString(random.nextInt(randString
.length())));
randomString += rand;
g.translate(random.nextInt(3), random.nextInt(3));
g.drawString(rand, 13 * i, 16);
return randomString;
}

/*
* 绘制干扰线
*/
private void drowLine(Graphics g) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(13);
int yl = random.nextInt(15);
g.drawLine(x, y, x + xl, y + yl);
}

/*
* 获取随机的字符
*/
public String getRandomString(int num) {
return String.valueOf(randString.char