以下为原始代码,可能是因为JDK1.4.2之后版本(例如:JDK1.4.2_08或者之后版本)不支持还是怎么的,出现
javax.imageio.IIOException: Can't create output stream!错误
<%
@ page contentType
=
"
image/jpeg
"
import
=
"
java.awt.*,java.awt.image.*,java.util.*,javax.imageio.*,com.sun.image.codec.jpeg.JPEGCodec,com.sun.image.codec.jpeg.JPEGImageEncoder;
"
%><%!

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);
}
%><%
//
response.setHeader(
"
Pragma
"
,
"
No-cache
"
);
response.setHeader(
"
Cache-Control
"
,
"
no-cache
"
);
response.setDateHeader(
"
Expires
"
,
0
);
//
int
width
=
60
, height
=
20
;
BufferedImage image
=
new
BufferedImage(width, height, BufferedImage.TYPE_INT_RGB);
Graphics g
=
image.getGraphics();
Random random
=
new
Random();
g.setColor(getRandColor(
200
,
250
));
g.fillRect(
0
,
0
, width, height);
g.setFont(
new
Font(
"
Times New Roman
"
,Font.PLAIN,
18
));
//
g.setColor(new Color());
//
g.drawRect(0,0,width-1,height-1);
g.setColor(getRandColor(
160
,
200
));
for
(
int
i
=
0
;i
<
155
;i
++
)

...
{
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x,y,x+xl,y+yl);
}
//
String sRand
=
""
;

for
(
int
i
=
0
;i
<
4
;i
++
)
...
{
String rand=String.valueOf(random.nextInt(10));
sRand+=rand;
//
g.setColor(new Color(20+random.nextInt(110),20+random.nextInt(110),20+random.nextInt(110)));
//
g.drawString(rand,13*i+6,16);
}
//
request.getSession().setAttribute(
"
checkcode
"
,sRand);
//
g.dispose();
//
ImageIO.write(image, "jpeg", response.getOutputStream());
%>
最后一行
ImageIO.write(image, "jpeg", response.getOutputStream());
修改为
JPEGImageEncoder encoder = JPEGCodec.createJPEGEncoder(response.getOutputStream());
encoder.encode(image);
就可以了。
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