diff --git a/spring-security/src/main/java/com/spring/security1/config/auth/PrincipalDetails.java b/spring-security/src/main/java/com/spring/security1/config/auth/PrincipalDetails.java
index fdb760d4..ad6b8e70 100644
--- a/spring-security/src/main/java/com/spring/security1/config/auth/PrincipalDetails.java
+++ b/spring-security/src/main/java/com/spring/security1/config/auth/PrincipalDetails.java
@@ -9,13 +9,17 @@ package com.spring.security1.config.auth;
 // Security Session => Authentication => UserDetails
 
 import com.spring.security1.model.User;
+import lombok.Data;
 import org.springframework.security.core.GrantedAuthority;
 import org.springframework.security.core.userdetails.UserDetails;
+import org.springframework.security.oauth2.core.user.OAuth2User;
 
 import java.util.ArrayList;
 import java.util.Collection;
+import java.util.Map;
 
-public class PrincipalDetails implements UserDetails {
+@Data
+public class PrincipalDetails implements UserDetails, OAuth2User {
 
     private User user;
 
@@ -68,4 +72,14 @@ public class PrincipalDetails implements UserDetails {
         // 현재시간 - 로그인 시간 => 1년을 초과하면 false 리턴
         return true;
     }
+
+    @Override
+    public Map<String, Object> getAttributes() {
+        return null;
+    }
+    
+    @Override
+    public String getName() {
+        return null;
+    }
 }
diff --git a/spring-security/src/main/java/com/spring/security1/config/oauth/PrincipalOauth2UserService.java b/spring-security/src/main/java/com/spring/security1/config/oauth/PrincipalOauth2UserService.java
index 5946bc20..116dd925 100644
--- a/spring-security/src/main/java/com/spring/security1/config/oauth/PrincipalOauth2UserService.java
+++ b/spring-security/src/main/java/com/spring/security1/config/oauth/PrincipalOauth2UserService.java
@@ -12,10 +12,13 @@ public class PrincipalOauth2UserService extends DefaultOAuth2UserService {
     // 구글로부터 받은 userRequest 데이터에 대한 후처리 되는 함수
     @Override
     public OAuth2User loadUser(OAuth2UserRequest userRequest) throws OAuth2AuthenticationException {
-        System.out.println("userRequest: "+ userRequest.getClientRegistration());
+        System.out.println("userRequest: "+ userRequest.getClientRegistration()); // registrationId로 어떤oauth로 로그인했는지 확인가능.
         System.out.println("userRequest: "+ userRequest.getAccessToken().getTokenValue());
+        // 구글 로그인 버튼 클릭 -> 구글 로그인 창 -> 로그인을 완료 -> code를 리턴(OAuth-Client 라이브러리) -> AccessToken 요청
+        // userRequest 정보 -> loadUser함수 -> 구글로 부터 회원 프로필 받아준다.
         System.out.println("userRequest: "+ super.loadUser(userRequest).getAttributes());
 
+        OAuth2User auth2User = super.loadUser(userRequest);
         return super.loadUser(userRequest);
     }
 }
diff --git a/spring-security/src/main/java/com/spring/security1/controller/IndexController.java b/spring-security/src/main/java/com/spring/security1/controller/IndexController.java
index 6f896ab2..63666394 100644
--- a/spring-security/src/main/java/com/spring/security1/controller/IndexController.java
+++ b/spring-security/src/main/java/com/spring/security1/controller/IndexController.java
@@ -1,11 +1,16 @@
 package com.spring.security1.controller;
 
+import com.spring.security1.config.auth.PrincipalDetails;
 import com.spring.security1.model.User;
 import com.spring.security1.repository.UserRepository;
 import lombok.RequiredArgsConstructor;
 import org.springframework.security.access.annotation.Secured;
 import org.springframework.security.access.prepost.PreAuthorize;
+import org.springframework.security.core.Authentication;
+import org.springframework.security.core.annotation.AuthenticationPrincipal;
+import org.springframework.security.core.userdetails.UserDetails;
 import org.springframework.security.crypto.bcrypt.BCryptPasswordEncoder;
+import org.springframework.security.oauth2.core.user.OAuth2User;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.GetMapping;
 import org.springframework.web.bind.annotation.PostMapping;
@@ -18,6 +23,30 @@ public class IndexController {
     private final UserRepository userRepository;
     private final BCryptPasswordEncoder bCryptPasswordEncoder;
 
+    @ResponseBody
+    @GetMapping("/test/login")
+    public String testLogin(Authentication authentication,
+                            @AuthenticationPrincipal PrincipalDetails userDetails) {
+        System.out.println("/test/logtin ================");
+        PrincipalDetails principalDetails = (PrincipalDetails) authentication.getPrincipal();
+        System.out.println("authentication: " + principalDetails.getUser());
+
+        System.out.println("userDetails: " + userDetails.getUser());
+        return "세션 정보 확인하기";
+    }
+
+    @ResponseBody
+    @GetMapping("/test/oauth/login")
+    public String testOAuthLogin(Authentication authentication,
+                                 @AuthenticationPrincipal OAuth2User oAuth) {
+        System.out.println("/test/logtin ================");
+        OAuth2User oAuth2User = (OAuth2User) authentication.getPrincipal();
+        System.out.println("authentication: " + oAuth2User.getAttributes());
+        System.out.println("Oauth2User: " + oAuth.getAttributes());
+
+        return "OAuth 세션 정보 확인하기";
+    }
+
     @GetMapping({"", "/"})
     public String index() {
         // 머스테치 기본폴더 src/main/resources/