@Override
    public void read(org.apache.thrift.protocol.TProtocol prot, TScan struct) throws org.apache.thrift.TException {
      org.apache.thrift.protocol.TTupleProtocol iprot = (org.apache.thrift.protocol.TTupleProtocol) prot;
      java.util.BitSet incoming = iprot.readBitSet(18);
      if (incoming.get(0)) {
        struct.startRow = iprot.readBinary();
        struct.setStartRowIsSet(true);
      }
      if (incoming.get(1)) {
        struct.stopRow = iprot.readBinary();
        struct.setStopRowIsSet(true);
      }
      if (incoming.get(2)) {
        {
          org.apache.thrift.protocol.TList _list123 = iprot.readListBegin(org.apache.thrift.protocol.TType.STRUCT);
          struct.columns = new java.util.ArrayList<TColumn>(_list123.size);
          @org.apache.thrift.annotation.Nullable TColumn _elem124;
          for (int _i125 = 0; _i125 < _list123.size; ++_i125)
          {
            _elem124 = new TColumn();
            _elem124.read(iprot);
            struct.columns.add(_elem124);
          }
        }
        struct.setColumnsIsSet(true);
      }
      if (incoming.get(3)) {
        struct.caching = iprot.readI32();
        struct.setCachingIsSet(true);
      }
      if (incoming.get(4)) {
        struct.maxVersions = iprot.readI32();
        struct.setMaxVersionsIsSet(true);
      }
      if (incoming.get(5)) {
        struct.timeRange = new TTimeRange();
        struct.timeRange.read(iprot);
        struct.setTimeRangeIsSet(true);
      }
      if (incoming.get(6)) {
        struct.filterString = iprot.readBinary();
        struct.setFilterStringIsSet(true);
      }
      if (incoming.get(7)) {
        struct.batchSize = iprot.readI32();
        struct.setBatchSizeIsSet(true);
      }
      if (incoming.get(8)) {
        {
          org.apache.thrift.protocol.TMap _map126 = iprot.readMapBegin(org.apache.thrift.protocol.TType.STRING, org.apache.thrift.protocol.TType.STRING); 
          struct.attributes = new java.util.HashMap<java.nio.ByteBuffer,java.nio.ByteBuffer>(2*_map126.size);
          @org.apache.thrift.annotation.Nullable java.nio.ByteBuffer _key127;
          @org.apache.thrift.annotation.Nullable java.nio.ByteBuffer _val128;
          for (int _i129 = 0; _i129 < _map126.size; ++_i129)
          {
            _key127 = iprot.readBinary();
            _val128 = iprot.readBinary();
            struct.attributes.put(_key127, _val128);
          }
        }
        struct.setAttributesIsSet(true);
      }
      if (incoming.get(9)) {
        struct.authorizations = new TAuthorization();
        struct.authorizations.read(iprot);
        struct.setAuthorizationsIsSet(true);
      }
      if (incoming.get(10)) {
        struct.reversed = iprot.readBool();
        struct.setReversedIsSet(true);
      }
      if (incoming.get(11)) {
        struct.cacheBlocks = iprot.readBool();
        struct.setCacheBlocksIsSet(true);
      }
      if (incoming.get(12)) {
        {
          org.apache.thrift.protocol.TMap _map130 = iprot.readMapBegin(org.apache.thrift.protocol.TType.STRING, org.apache.thrift.protocol.TType.STRUCT); 
          struct.colFamTimeRangeMap = new java.util.HashMap<java.nio.ByteBuffer,TTimeRange>(2*_map130.size);
          @org.apache.thrift.annotation.Nullable java.nio.ByteBuffer _key131;
          @org.apache.thrift.annotation.Nullable TTimeRange _val132;
          for (int _i133 = 0; _i133 < _map130.size; ++_i133)
          {
            _key131 = iprot.readBinary();
            _val132 = new TTimeRange();
            _val132.read(iprot);
            struct.colFamTimeRangeMap.put(_key131, _val132);
          }
        }
        struct.setColFamTimeRangeMapIsSet(true);
      }
      if (incoming.get(13)) {
        struct.readType = org.apache.hadoop.hbase.thrift2.generated.TReadType.findByValue(iprot.readI32());
        struct.setReadTypeIsSet(true);
      }
      if (incoming.get(14)) {
        struct.limit = iprot.readI32();
        struct.setLimitIsSet(true);
      }
      if (incoming.get(15)) {
        struct.consistency = org.apache.hadoop.hbase.thrift2.generated.TConsistency.findByValue(iprot.readI32());
        struct.setConsistencyIsSet(true);
      }
      if (incoming.get(16)) {
        struct.targetReplicaId = iprot.readI32();
        struct.setTargetReplicaIdIsSet(true);
      }
      if (incoming.get(17)) {
        struct.filterBytes = iprot.readBinary();
        struct.setFilterBytesIsSet(true);
      }
    }
Returns true if field corresponding to fieldID is set (has been assigned a value) and false otherwise
hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift2/generated/TScan.java