java.net.ProtocolException: Exceeded stated content-length of: '668' bytes

[wjw200404]

实现文件下载的代码如下：
response.reset();
response.setContentType("application/octet-stream");
response.setContentLength((int) file.length());
response.setHeader("Content-Disposition", "attachment; filename =" + URLEncoder.encode(fileName, "UTF-8"));
fileInputStream = new FileInputStream(file);
bufferedInputStream = new BufferedInputStream(fileInputStream);
byte[] b = new byte[1024];
int size = 0;
outputStream = response.getOutputStream();
while ((size = bufferedInputStream.read(b)) != -1) {
outputStream.write(b, 0, size);
}
下载时，出现如下异常：
error 500--internal server error
java.net.ProtocolException: Exceeded stated content-length of: '339' bytes
at weblogic.servlet.internal.ServletOutputStreamImpl.checkCL(ServletOutputStreamImpl.java:220)
at weblogic.servlet.internal.ServletOutputStreamImpl.write(ServletOutputStreamImpl.java:167)
at java.io.OutputStream.write(OutputStream.java:58)

求助！