code: public boolean pinOnce()
      {
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              Tr.entry(tc, "pinOnce: " + ivBeanId);
  
          boolean pinnedOnce = false;
  
          synchronized (ivBucket)
          {
              if (pinned == 0)
              {
                  pinned++;
                  pinnedOnce = true;
              }
          }
  
          if (TraceComponent.isAnyTracingEnabled() && tc.isEntryEnabled())
              Tr.exit(tc, "pinOnce : " + pinned);
  
          return pinnedOnce;
      }
docs: d195605