For example:

in src/hotspot/share/cds/metaspaceShared.cpp:
class CountSharedSymbols : public SymbolClosure {
 private:
   int _count;

src/hotspot/share/classfile/symbolTable.cpp:
   return CompactHashtableWriter::estimate_size(int(_items_cont));
    ....
   CompactHashtableWriter writer(int(_items_count), ArchiveBuilder::symbol_stats());

For clarity, it's better to use size_t for these counters (even if we know that there will be fewer than 0x7fffffff symbols due to ArchiveBuilder::MAX_SHARED_DELTA).