ChineseVal.jsp
<%@
page
pageEncoding
=
"gb2312" contentType="image/jpeg"
import
=
"javax.imageio.*,java.util.*,java.awt.image.*,java.awt.*"
%>
<%!
//在此处
获取并生成随机颜色
Color getRandColor(Random random,
int
ff,
int
cc) {
if
(ff > 255)
ff = 255;
if
(cc > 255)
cc = 255;
int
r = ff + random.nextInt(cc - ff);
int
g = ff + random.nextInt(cc - ff);
int
b = ff + random.nextInt(cc - ff);
return
new
Color(r, g, b);
}
%>
<%
//在此处
设置JSP页面无缓存
response.setHeader(
"Pragma"
,
"No-cache"
);
response.setHeader(
"Cache-Control"
,
"no-cache"
);
response.setDateHeader(
"Expires"
, 0);
//
设置图片的长宽
int
width = 130;
int height = 30;
//设定被随机选取的中文字，此处中文字内容过多，不一一列出，只是举例说明下。
String base =
"\u9752\u534a\u706b\u6cd5\u9898\u5efa\u8d76\u4f4d\u5531\u6d77\u4e03\u5973\u4efb\u4ef6\u611f\u51c6\u97f3\u7b54\u54e5\u9645\u65e7\u795e\u5ea7\u7ae0\u538b\u6162\u53d4\u80cc\u7ec6...省略文字。。。"
;
//设置
备选随机汉字的个数
int
length = base.length();
//
创建缓存图像
BufferedImage image =
new
BufferedImage(width, height,
BufferedImage.TYPE_INT_RGB);
//
获取图像
Graphics g = image.getGraphics();
//
创建随机函数的实例
Random random =
new
Random();
//此处
设定图像背景色
g.setColor(getRandColor(random, 188, 235));
g.fillRect(0, 0, width, height);
//设置随机
备选的字体类型
String[] fontTypes = {
"\u5b8b\u4f53"
,
"\u65b0\u5b8b\u4f53"
,
"\u9ed1\u4f53"
,
"\u6977\u4f53"
,
"\u96b6\u4e66"
};
int
fontTypesLength = fontTypes.length;
//
在图片背景上增加噪点，增加图片分析难度
g.setColor(getRandColor(random, 180, 199));
g.setFont(
new
Font(
"Times New Roman"
, Font.PLAIN, 14));
for
(
int
i = 0; i < 4; i++) {
g.drawString(
"@*@*@*@*@*@*@*"
,
0, 5 * (i + 2));
}
//
取随机产生的验证码
(4
个汉字
)
//
保存生成的汉字字符串
String sRand =
""
;
for
(
int
i = 0; i < 4; i++) {
int
start = random.nextInt(length);
String rand = base.substring(start, start + 1);
sRand += rand;
//
设置图片上字体的颜色
g.setColor(getRandColor(random, 10, 150));
//
设置字体格式
g.setFont(
new
Font(fontTypes[random.nextInt(fontTypesLength)],
Font.BOLD, 18 + random.nextInt(6)));
//
将此汉字画到验证图片上面
g.drawString(rand, 24 * i + 10 + random.nextInt(8), 24);
}
//
将验证码存入S
ession中
session.setAttribute(
"rand"
, sRand);
g.dispose();
//将
图象输出到JSP页面中
ImageIO.write(image,
"JPEG"
, response.getOutputStream());
//关闭流
out.clear();
out=pageContext.pushBody();
%>