// Unmarked shared Strings in the StringTable (which got there due to
// being in the constant pools of as-yet unloaded shared classes) were
// not marked and therefore did not have their mark words preserved.
// These entries are also deliberately not purged from the string
// table during unloading of unmarked strings. If an identity hash
// code was computed for any of these objects, it will not have been
// cleared to zero during the forwarding process or by the
// RecursiveAdjustSharedObjectClosure, and will be confused by the
// adjusting process as a forwarding pointer. We need to skip
// forwarding StringTable entries which contain unmarked shared
// Strings. Actually, since shared strings won't be moving, we can
// just skip adjusting any shared entries in the string table.

void SharedHeap::process_weak_roots(OopClosure* root_closure,
                                    CodeBlobClosure* code_roots,
                                    OopClosure* non_root_closure) {

  {- -------------------------------------------
  (1) Weak global JNI references に対して処理を行う.
      ---------------------------------------- -}

      // Global (weak) JNI handles
      JNIHandles::weak_oops_do(&always_true, root_closure);

  {- -------------------------------------------
  (1) 
      ---------------------------------------- -}

      CodeCache::blobs_do(code_roots);
      if (UseSharedSpaces && !DumpSharedSpaces) {
        SkipAdjustingSharedStrings skip_closure(root_closure);
        StringTable::oops_do(&skip_closure);
      } else {
        StringTable::oops_do(root_closure);
      }
    }