BooleanBuilder public void dynamicQuery_BooleanBuilder() { String usernameParam = "member1"; Integer ageParam = null; List result = searchMember(usernameParam, ageParam); } private List searchMember(String usernameCond, Integer ageCond) { BooleanBuilder builder = new BooleanBuilder(); if (usernameCond != null) builder.and(member.username.eq(usernameCond)); } if (ageCond != null) { builder.and(me..