code: public static void writeUnsignedVarLong(long value, DataOutputStream out) throws IOException {
          while ((value & 0xFFFFFFFFFFFFFF80L) != 0L) {
              out.writeByte(((int) value & 0x7F) | 0x80);
              value >>>= 7;
          }
          out.writeByte((int) value & 0x7F);
      }
docs: Encodes a value using the variable-length encoding from
  <a href="http://code.google.com/apis/protocolbuffers/docs/encoding.html">
  Google Protocol Buffers</a>. Zig-zag is not used, so input must not be negative.
  If values can be negative, use {@link #writeSignedVarLong(long, java.io.DataOutputStream)}
  instead. This method treats negative input as like a large unsigned value.
  
  @param value value to encode
  @param out to write bytes to
  @throws java.io.IOException if {@link java.io.DataOutputStream} throws {@link java.io.IOException}