code: public void enter(Symbol sym, Scope s, Scope origin, boolean staticallyImported) {
          Assert.check(shared == 0);
          if (nelems * 3 >= hashMask * 2)
              dble();
          int hash = getIndex(sym.name);
          Entry old = table[hash];
          if (old == null) {
              old = sentinel;
              nelems++;
          }
          Entry e = makeEntry(sym, old, elems, s, origin, staticallyImported);
          table[hash] = e;
          elems = e;
  
          //notify listeners
          for (List<ScopeListener> l = listeners; l.nonEmpty(); l = l.tail) {
              l.head.symbolAdded(sym, this);
          }
      }
docs: Enter symbol sym in this scope, but mark that it comes from
  given scope `s' accessed through `origin'.  The last two
  arguments are only used in import scopes.