public static void writeByteArray(final DataOutput out, final byte[] b, final int offset,
                                      final int length) throws IOException {
        WritableUtils.writeVInt(out, length);
        out.write(b, offset, length);
    }
Write byte-array to out with a vint length prefix.

@param out    output stream
@param b      array
@param offset offset into array
@param length length past offset
@throws IOException e
stroom-bytebuffer/src/main/java/stroom/bytebuffer/hbase/Bytes.java