code: @Override
      public void setDestroyConnectionOnReturn() {
  
          final boolean isTracingEnabled = TraceComponent.isAnyTracingEnabled();
  
          if (isTracingEnabled && tc.isEntryEnabled()) {
              Tr.entry(this, tc, "setDestroyConnectionOnReturn");
          }
  
          --fatalErrorValue;
          if (isTracingEnabled && tc.isEntryEnabled()) {
              Tr.exit(this, tc, "setDestroyConnectionOnReturn", fatalErrorValue);
          }
  
      }
docs: This method is used for marking a connection to destroy.
  The connection state does not matter. The connection still
  can be useable. When the connection is returned to the
  free pool, this connection will be cleaned up and destroyed.
  
  This method may be called when total connection count is being
  decreased.