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());%>
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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