code: public static final boolean isContainerAtBoundary(EmbeddableWebSphereTransactionManager tm) {
          boolean isContainerResolved = false; // RESOLVER_APPLICATION - the default
          UOWCurrent uowCurrent = (UOWCurrent) tm;
          UOWCoordinator uowCoord = uowCurrent == null ? null : uowCurrent.getUOWCoord();
  
          if (uowCoord != null) {
              if (!uowCoord.isGlobal()) { 
                  isContainerResolved = ((LocalTransactionCoordinator) uowCoord).isContainerResolved();
              } else { 
                  if (tc.isDebugEnabled()) {
                      Tr.debug(tc, "isContainerAtBoundary unexpectedly called within a global tran and the value is defaulted to APPLICATION");
                  }
              } 
          }
  
          if (tc.isDebugEnabled())
              Tr.debug(tc, "isContainerAtBoundary=" + isContainerResolved); 
  
          return isContainerResolved;
  
      }
docs: The <b>res-resolution-control</b> local transaction property specifies for relational
  resource adapters the resolution control to be used by the backend database.
  
  @param tm transaction manager
  @return True if resolution control is "ContainerAtBoundary". False if "Application".