Most effective way to write File to ServletOutputStream

Question

ServletOutputStream output = response.getOutputStream();
output.write(byte[]);

What is the most effective way to write File to javax.servlet.Servle

Answer 1

If you don't want to add that jar to your application then you have to copy it by hand. Just copy the method implementation from here: http://svn.apache.org/viewvc/commons/proper/io/trunk/src/main/java/org/apache/commons/io/IOUtils.java?revision=1004358&view=markup:

private static final int DEFAULT_BUFFER_SIZE = 1024 * 4;

public static int copy(InputStream input, OutputStream output) throws IOException {
  long count = copyLarge(input, output);
  if (count > Integer.MAX_VALUE) {
    return -1;
  }
  return (int) count;
}

public static long copyLarge(InputStream input, OutputStream output)
    throws IOException {
   byte[] buffer = new byte[DEFAULT_BUFFER_SIZE];
   long count = 0;
   int n = 0;
   while (-1 != (n = input.read(buffer))) {
     output.write(buffer, 0, n);
     count += n;
   }
   return count;
}

put those 2 methods in one of your helper classes and you're good to go.