void JvmtiBreakpoint::each_method_version_do(method_action meth_act) {

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

      ((methodOopDesc*)_method->*meth_act)(_bci);

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

      // add/remove breakpoint to/from versions of the method that
      // are EMCP. Directly or transitively obsolete methods are
      // not saved in the PreviousVersionInfo.

  {- -------------------------------------------
  (1) (変数宣言など)
      ---------------------------------------- -}

      Thread *thread = Thread::current();
      instanceKlassHandle ikh = instanceKlassHandle(thread, _method->method_holder());
      Symbol* m_name = _method->name();
      Symbol* m_signature = _method->signature();

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

      {
        ResourceMark rm(thread);
        // PreviousVersionInfo objects returned via PreviousVersionWalker
        // contain a GrowableArray of handles. We have to clean up the
        // GrowableArray _after_ the PreviousVersionWalker destructor
        // has destroyed the handles.
        {
          // search previous versions if they exist
          PreviousVersionWalker pvw((instanceKlass *)ikh()->klass_part());
          for (PreviousVersionInfo * pv_info = pvw.next_previous_version();
               pv_info != NULL; pv_info = pvw.next_previous_version()) {
            GrowableArray<methodHandle>* methods =
              pv_info->prev_EMCP_method_handles();

            if (methods == NULL) {
              // We have run into a PreviousVersion generation where
              // all methods were made obsolete during that generation's
              // RedefineClasses() operation. At the time of that
              // operation, all EMCP methods were flushed so we don't
              // have to go back any further.
              //
              // A NULL methods array is different than an empty methods
              // array. We cannot infer any optimizations about older
              // generations from an empty methods array for the current
              // generation.
              break;
            }

            for (int i = methods->length() - 1; i >= 0; i--) {
              methodHandle method = methods->at(i);
              if (method->name() == m_name && method->signature() == m_signature) {
                RC_TRACE(0x00000800, ("%sing breakpoint in %s(%s)",
                  meth_act == &methodOopDesc::set_breakpoint ? "sett" : "clear",
                  method->name()->as_C_string(),
                  method->signature()->as_C_string()));
                assert(!method->is_obsolete(), "only EMCP methods here");

                ((methodOopDesc*)method()->*meth_act)(_bci);
                break;
              }
            }
          }
        } // pvw is cleaned up
      } // rm is cleaned up
    }