@Override
        public Builder addMember(MemberShape member) {
            if (!member.getTarget().equals(UnitTypeTrait.UNIT)) {
                throw new SourceException(String.format(
                        "intEnum members may only target `smithy.api#Unit`, but found `%s`",
                        member.getTarget()), getSourceLocation());
            }
            members.get().put(member.getMemberName(), member);

            return this;
        }
Replaces the members of the builder.

@param members Members to add to the builder.
@return Returns the builder.
smithy-model/src/main/java/software/amazon/smithy/model/shapes/IntEnumShape.java