问如何获取ByteArrayInputStream并将其内容另存为文件系统上的文件

EN

 IOUtils.copy(byteArrayInputStream, new FileOutputStream(outputFileName));

InputStream in = //your ByteArrayInputStream here
OutputStream out = new FileOutputStream("filename.jpg");

// Transfer bytes from in to out
byte[] buf = new byte[1024];
int len;
while ((len = in.read(buf)) > 0) {
    out.write(buf, 0, len);
}
in.close();
out.close();

ByteArrayInputStream input = getInputStream();
FileOutputStream output = new FileOutputStream(outputFilename);

int DEFAULT_BUFFER_SIZE = 1024;
byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
long count = 0;
int n = 0;

n = input.read(buffer, 0, DEFAULT_BUFFER_SIZE);

while (n >= 0) {
   output.write(buffer, 0, n);
   n = input.read(buffer, 0, DEFAULT_BUFFER_SIZE);
}