refactor: nullSafeBooleanBuilder로 NPE를 방지한다.

src/main/java/com/moneymong/domain/agency/repository/AgencyRepositoryImpl.java

@@ -2,6 +2,7 @@
 
 import com.moneymong.domain.agency.entity.Agency;
 import com.moneymong.domain.agency.entity.enums.AgencyType;
+import com.querydsl.core.BooleanBuilder;
 import com.querydsl.core.types.dsl.BooleanExpression;
 import com.querydsl.jpa.impl.JPAQuery;
 import com.querydsl.jpa.impl.JPAQueryFactory;
@@ -12,6 +13,7 @@
 import org.springframework.stereotype.Repository;
 
 import java.util.List;
+import java.util.function.Supplier;
 
 import static com.moneymong.domain.agency.entity.QAgency.agency;
 
@@ -38,7 +40,7 @@ public Page<Agency> findByUniversityNameByPaging(String universityName, Pageable
     public Page<Agency> findByUniversityNameAndAgencyTypeByPaging(String universityName, AgencyType type,
         Pageable pageable) {
         JPAQuery<Agency> query = queryFactory.selectFrom(agency)
-            .where(eqUniversityName(universityName).or(agency.agencyType.eq(type)))
+            .where(agency.agencyType.eq(type).or(eqUniversityName(universityName)))
             .limit(pageable.getPageSize())
             .offset(pageable.getOffset());
 
@@ -58,7 +60,16 @@ private JPAQuery<Agency> getCountQuery(String universityName, AgencyType type) {
         return queryFactory.selectFrom(agency)
             .where(eqUniversityName(universityName).or(agency.agencyType.eq(type)));
     }
-    private BooleanExpression eqUniversityName(String universityName) {
-        return universityName != null ? agency.universityName.eq(universityName) : null;
+
+    private BooleanBuilder eqUniversityName(String universityName) {
+        return nullSafeBooleanBuilder(() -> agency.universityName.eq(universityName));
+    }
+
+    private BooleanBuilder nullSafeBooleanBuilder(Supplier<BooleanExpression> supplier) {
+        try {
+            return new BooleanBuilder(supplier.get());
+        } catch (IllegalArgumentException e) {
+            return new BooleanBuilder();
+        }
     }
 }