code: public Map<String, String> getRoleMap() {
          if (mapAllMethods != null) {
              return getRoleMapFromAllMap();
          }
          Map<String, List<String>> outputRTMNormal = null;
          Map<String, List<String>> outputRTMOmission = null;
  
          if (mapMethod != null) {
              outputRTMNormal = getRoleToMethodMap(getMethod(mapMethod, ROLE, true));
              if (tc.isDebugEnabled())
                  Tr.debug(tc, "outputRTMNormal: " + outputRTMNormal);
          }
          if (mapMethodOmission != null) {
              // it genereate output only following condition:
              // 1.role is assigned.
              // 2.neither unchecked or excluded.
              Map<String, MethodConstraint> omissionRole = getMethod(mapMethodOmission, ROLE_NO_CHECK, true);
              Map<String, MethodConstraint> validRole = getMethod(mapMethodOmission, EXCLUDED_OR_UNCHECKED_NO_ROLE, true);
              Map<String, MethodConstraint> uncheckedOrExcluded = getMethod(mapMethodOmission, EXCLUDED_OR_UNCHECKED, true);
  
              if (tc.isDebugEnabled())
                  Tr.debug(tc, "omissionRole: " + omissionRole + " validRole : " + validRole + " uncheckedOrExcluded : " + uncheckedOrExcluded);
              if (omissionRole != null && ((uncheckedOrExcluded != null && validRole != null) || uncheckedOrExcluded == null)) {
                  outputRTMOmission = getRoleToMethodMap(omissionRole);
                  if (tc.isDebugEnabled())
                      Tr.debug(tc, "outputRTMOmission: " + outputRTMOmission);
              }
          }
  
          // now merge both tables and generate method strings.
          Map<String, String> output = mergeRTM(outputRTMNormal, outputRTMOmission);
          if (tc.isDebugEnabled())
              Tr.debug(tc, "getRoleMap: output: " + output);
          return output;
      }
docs: In here, null is used to represent all methods.