code: @Override
      public int getIsolationLevel() {
          if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled())
              Tr.debug(tc, "getIsolationLevel : " + currentIsolationLevel);
          return currentIsolationLevel;
      }
docs: Get isolation level currently associated with this session
  bean instance. This is used for determining the isolation level
  to use in a bean managed transaction.
  
  The current isolation level is maintained in a stack with the
  assistance of the EJSDeployedSupport instance passed to
  preInvoke/postInvoke.