code: public void reward(RuleContext kcontext, long weightMultiplier) {
          Rule rule = kcontext.getRule();
          BiConsumer<RuleContext, Long> matchExecutor = matchExecutorByNumberMap.get(rule);
          if (matchExecutor == null) {
              throw new IllegalStateException("The DRL rule (" + rule.getPackageName() + ":" + rule.getName()
                      + ") does not match a @" + ConstraintWeight.class.getSimpleName() + " on the @"
                      + ConstraintConfiguration.class.getSimpleName() + " annotated class.");
          }
          matchExecutor.accept(kcontext, weightMultiplier);
      }
docs: Reward a match by the {@link ConstraintWeight} multiplied with the weightMultiplier for all score levels.
  @param kcontext never null, the magic variable in DRL
  @param weightMultiplier at least 0