JSP彩色验证码，javax.imageio.IIOException: Can't create output stream! 解决方法

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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