157   // Unload classes and purge the SystemDictionary.

   157   {

   158   bool purged_class = SystemDictionary::do_unloading(&GenMarkSweep::is_alive);

   158     GCTraceTime(Debug, gc) trace("Class Unloading", gc_timer());

   159 

   159 

   160   // Unload nmethods.

   160     // Unload classes and purge the SystemDictionary.

   161   CodeCache::do_unloading(&GenMarkSweep::is_alive, purged_class);

   161     bool purged_class = SystemDictionary::do_unloading(&GenMarkSweep::is_alive);

   162 

   162 

   163   // Prune dead klasses from subklass/sibling/implementor lists.

   163     // Unload nmethods.

   164   Klass::clean_weak_klass_links(&GenMarkSweep::is_alive);

   164     CodeCache::do_unloading(&GenMarkSweep::is_alive, purged_class);

   165 

   165 

   166   // Delete entries for dead interned string and clean up unreferenced symbols in symbol table.

   166     // Prune dead klasses from subklass/sibling/implementor lists.

   167   g1h->unlink_string_and_symbol_table(&GenMarkSweep::is_alive);

   167     Klass::clean_weak_klass_links(&GenMarkSweep::is_alive);

   168   }

   169 

   170   {

   171     GCTraceTime(Debug, gc) trace("Scrub String and Symbol Tables", gc_timer());

   172     // Delete entries for dead interned string and clean up unreferenced symbols in symbol table.

   173     g1h->unlink_string_and_symbol_table(&GenMarkSweep::is_alive);

   174   }

   175 

   176   if (G1StringDedup::is_enabled()) {

   177     GCTraceTime(Debug, gc) trace("String Deduplication Unlink", gc_timer());

   178     G1StringDedup::unlink(&GenMarkSweep::is_alive);

   179   }