spring data jpa : custom repository

spring-data-jpa/src/main/java/com/example/springdatajpa/repository/MemberRepository.java

@@ -14,7 +14,7 @@ import java.util.Collection;
 import java.util.List;
 import java.util.Optional;
 
-public interface MemberRepository extends JpaRepository<Member, Long> {
+public interface MemberRepository extends JpaRepository<Member, Long>, MemberRepositoryCustom{
 
     List<Member> findByUsernameAndAgeGreaterThan(String username, int age);
 

spring-data-jpa/src/main/java/com/example/springdatajpa/repository/MemberRepositoryCustom.java

@@ -0,0 +1,10 @@
+package com.example.springdatajpa.repository;
+
+import com.example.springdatajpa.entity.Member;
+
+import java.util.List;
+
+public interface MemberRepositoryCustom {
+
+    List<Member> findMemberCustom();
+}

spring-data-jpa/src/main/java/com/example/springdatajpa/repository/MemberRepositoryImpl.java

@@ -0,0 +1,19 @@
+package com.example.springdatajpa.repository;
+
+import com.example.springdatajpa.entity.Member;
+import lombok.RequiredArgsConstructor;
+
+import javax.persistence.EntityManager;
+import java.util.List;
+
+@RequiredArgsConstructor
+public class MemberRepositoryImpl implements MemberRepositoryCustom {
+
+    private final EntityManager em;
+
+    @Override
+    public List<Member> findMemberCustom() {
+        return em.createQuery("select m from Member m", Member.class)
+                .getResultList();
+    }
+}

spring-data-jpa/src/test/java/com/example/springdatajpa/repository/MemberRepositoryTest.java

@@ -306,5 +306,11 @@ public class MemberRepositoryTest {
         Member findMember = memberRepository.findLockByUsername("member1");
 
     }
+
+    @Test
+    void callCustom() {
+        List<Member> result = memberRepository.findMemberCustom();
+
+    }
 }