code: private void involveMCInTran(MCWrapper mcWrapper, UOWCoordinator uowCoord, com.ibm.ejs.j2c.ConnectionManager inUseCM) throws ResourceException {
  
          final boolean isTraceOn = TraceComponent.isAnyTracingEnabled();
          if (isTraceOn && tc.isEntryEnabled()) {
              Tr.entry(this, tc, "involveMCInTran", inUseCM.toString());
          }
  
          if (!mcWrapper.involvedInTransaction()) { // this whole first part of the if statement is new.
  
              // Not involved in transaction, need to get involved in transaction.
              // Set a Reference to this CM instance into the McWrapper
              mcWrapper.setConnectionManager(inUseCM);
  
              /*
               * If isEnlistmentDisabled is true, log a message and return.
               */
              if (mcWrapper.isEnlistmentDisabled()) {
  
                  if (isTraceOn && tc.isDebugEnabled()) {
                      Tr.debug(this, tc, "Managed connection isEnlistmentDisabled is true.");
                      Tr.debug(this, tc, "Returning without calling method initializeForUOW.");
                  }
                  if (isTraceOn && tc.isEntryEnabled()) {
                      Tr.exit(this, tc, "involveMCInTran");
                  }
  
                  return;
  
              }
              mcWrapper.setUOWCoordinator(uowCoord);
  
              // Do the transactional setup if required.
              initializeForUOW(mcWrapper, false);
  
          }
  
          if (isTraceOn && tc.isEntryEnabled()) {
              Tr.exit(this, tc, "involveMCInTran");
          }
  
      }
docs: This method is called internally by the CM obtain a ManagedConnection wrapped in a MCWrapper.
  Used by: allocateConnection, reAssociate, and associateConnection.
  
  @param mcWrapper The managed connection wrapper to involve.