Method serializeOld

src/Scanner.java:1400–1461

Serializes this request for HBase 0.94 and before.

(final byte server_version)

    /** Serializes this request for HBase 0.94 and before.  */
    private ChannelBuffer serializeOld(final byte server_version) {
      final ChannelBuffer buf = newBuffer(server_version,
                                          predictSerializedSize());
      buf.writeInt(2);  // Number of parameters.

      // 1st param: byte array containing region name
      writeHBaseByteArray(buf, super.region.name());

      // 2nd param: Scan object
      buf.writeByte(39);   // Code for a `Scan' parameter.
      buf.writeByte(39);   // Code again (see HBASE-2877).
      buf.writeByte(1);    // Manual versioning of Scan.
      writeByteArray(buf, start_key);
      writeByteArray(buf, stop_key);
      buf.writeInt(versions);  // Max number of versions to return.

      // Max number of KeyValues to get per RPC.
      buf.writeInt(max_num_kvs);

      // Unused field, only used by HBase's client.  This value should represent
      // how many rows per call the client will fetch, but the server doesn't
      // care about this value, neither do we, because we use a different API.
      buf.writeInt(0xDEADBA5E);

      // Whether or not to populate the blockcache.
      buf.writeByte(populate_blockcache ? 0x01 : 0x00);

      if (filter == null) {
        buf.writeByte(0x00); // boolean (false): don't use a filter.
      } else {
        buf.writeByte(0x01); // boolean (true): use a filter.
        filter.serializeOld(buf);
      }

      // TimeRange
      buf.writeLong(min_timestamp);  // Minimum timestamp.
      buf.writeLong(max_timestamp);  // Maximum timestamp.
      // Boolean: "all time".
      buf.writeByte(min_timestamp != 0 || max_timestamp != Long.MAX_VALUE
                    ? 0x00 : 0x01);

      // Families.
      if (families != null) {
        buf.writeInt(families.length);  // Number of families that follow.
        for (int i = 0; i < families.length; i++) {
          // Each family is then written like so:
          writeByteArray(buf, families[i]);  // Column family name.
          if (qualifiers != null && qualifiers[i] != null) {
            buf.writeInt(qualifiers[i].length);  // How many qualifiers do we want?
            for (byte[] qualifier : qualifiers[i]) {
              writeByteArray(buf, qualifier);  // Column qualifier name.
            }
          } else {
            buf.writeInt(0);  // No qualifiers.
          }
        }
      } else {
        buf.writeInt(0);  // No families.