📝 Add docstrings to feat/#315

src/main/java/com/beat/BeatApplication.java

@@ -19,6 +19,14 @@
 @ImportAutoConfiguration({FeignAutoConfiguration.class})
 public class BeatApplication {
 
+	/**
+	 * Main entry point for the BeatApplication Spring Boot application.
+	 *
+	 * <p>This method bootstraps the application by invoking SpringApplication.run
+	 * with the BeatApplication class and the provided command-line arguments.</p>
+	 *
+	 * @param args command-line arguments passed to the application
+	 */
 	public static void main(String[] args) {
 		SpringApplication.run(BeatApplication.class, args);
 	}

src/main/java/com/beat/domain/member/application/MemberRegistrationService.java

@@ -24,6 +24,16 @@ public class MemberRegistrationService {
 	private final UserRepository userRepository;
 	private final MemberRepository memberRepository;
 
+	/**
+	 * Registers a new member and its associated user account.
+	 *
+	 * <p>This method creates a user with the MEMBER role and a corresponding member record using the
+	 * provided member information. It saves both entities transactionally and publishes a registration event
+	 * with the member's nickname.
+	 *
+	 * @param memberInfoResponse the data required for member registration, including nickname, email, social ID, and social type
+	 * @return the identifier of the newly registered member
+	 */
 	@Transactional
 	public Long registerMemberWithUserInfo(final MemberInfoResponse memberInfoResponse) {
 		Users users = Users.createWithRole(Role.MEMBER);

src/main/java/com/beat/domain/member/application/MemberService.java

@@ -36,13 +36,33 @@ public boolean checkMemberExistsBySocialIdAndSocialType(final Long socialId, fin
 		return memberRepository.findBySocialTypeAndSocialId(socialId, socialType).isPresent();
 	}
 
+	/**
+	 * Retrieves a member using the specified social ID and social type.
+	 * <p>
+	 * Searches the member repository for a member matching the provided social ID and social type.
+	 * If no such member exists, a NotFoundException with error code MEMBER_NOT_FOUND is thrown.
+	 *
+	 * @param socialId the unique social identifier of the member
+	 * @param socialType the social platform type associated with the member
+	 * @return the member corresponding to the given social credentials
+	 * @throws NotFoundException if no matching member is found
+	 */
 	@Override
 	@Transactional(readOnly = true)
 	public Member findMemberBySocialIdAndSocialType(final Long socialId, final SocialType socialType) {
 		return memberRepository.findBySocialTypeAndSocialId(socialId, socialType)
 			.orElseThrow(() -> new NotFoundException(MemberErrorCode.MEMBER_NOT_FOUND));
 	}
 
+	/**
+	 * Deletes a user identified by the specified ID.
+	 *
+	 * <p>This method retrieves the user from the repository and removes it. If no user is found with the
+	 * given ID, a {@link NotFoundException} is thrown with the error code {@link MemberErrorCode#MEMBER_NOT_FOUND}.
+	 *
+	 * @param id the unique identifier of the user to delete
+	 * @throws NotFoundException if no user with the specified ID is found
+	 */
 	@Override
 	@Transactional
 	public void deleteUser(final Long id) {
@@ -52,6 +72,11 @@ public void deleteUser(final Long id) {
 		userRepository.delete(users);
 	}
 
+	/**
+	 * Retrieves the total count of members.
+	 *
+	 * @return the total number of members
+	 */
 	@Override
 	@Transactional(readOnly = true)
 	public long countMembers() {

src/main/java/com/beat/domain/member/application/SocialLoginService.java

@@ -96,11 +96,14 @@ private LoginSuccessResponse generateLoginResponseFromMemberInfo(final MemberInf
 	}
 
 	/**
-	 * 사용자 정보(Social ID와 Social Type)를 통해 기존 회원을 찾거나,
-	 * 없으면 새로운 회원을 등록하는 메서드.
+	 * Finds an existing member by their social ID and social type, or registers a new member if none exists.
 	 *
-	 * @param memberInfoResponse 소셜 서비스에서 가져온 사용자 정보
-	 * @return 등록된 회원 또는 기존 회원의 ID
+	 * <p>This method checks whether a member with the specified social details (contained in
+	 * {@code memberInfoResponse}) already exists. If found, the member's ID is returned after logging
+	 * their role; otherwise, the method registers a new member using the provided information and returns the new member's ID.
+	 *
+	 * @param memberInfoResponse user information retrieved from the social service, including social ID and type
+	 * @return the ID of the existing or newly registered member
 	 */
 	private Long findOrRegisterMember(final MemberInfoResponse memberInfoResponse) {
 		boolean memberExists = memberUseCase.checkMemberExistsBySocialIdAndSocialType(memberInfoResponse.socialId(),

src/main/java/com/beat/domain/member/port/in/MemberUseCase.java

@@ -10,7 +10,17 @@ public interface MemberUseCase {
 
 	Member findMemberBySocialIdAndSocialType(Long socialId, SocialType socialType);
 
-	void deleteUser(Long id);
+	/**
+ * Deletes a user identified by the given ID.
+ *
+ * @param id the unique identifier of the user to delete
+ */
+void deleteUser(Long id);
 
-	long countMembers();
+	/**
+ * Returns the total number of members.
+ *
+ * @return the total member count
+ */
+long countMembers();
 }

src/main/java/com/beat/global/common/config/AsyncThreadConfig.java

@@ -21,6 +21,17 @@
 public class AsyncThreadConfig implements AsyncConfigurer {
 	private final ThreadPoolProperties threadPoolProperties;
 
+	/**
+	 * Creates and returns an Executor for asynchronous task execution.
+	 *
+	 * <p>The executor is configured with a core pool size and thread name prefix sourced from
+	 * the thread pool properties. It employs a CallerRunsPolicy to handle task rejections,
+	 * ensuring that when the pool is saturated, tasks execute in the calling thread.
+	 * The ThreadPoolTaskExecutor is wrapped in a DelegatingSecurityContextExecutor to preserve
+	 * the Spring Security context across asynchronous execution.
+	 *
+	 * @return the security-aware executor for asynchronous tasks
+	 */
 	@Override
 	@Bean(name = "taskExecutor")
 	public Executor getAsyncExecutor() {
@@ -32,6 +43,14 @@ public Executor getAsyncExecutor() {
 		return new DelegatingSecurityContextExecutor(executor.getThreadPoolExecutor());
 	}
 
+	/**
+	 * Returns the asynchronous uncaught exception handler.
+	 *
+	 * <p>This bean provides a global handler for uncaught exceptions thrown by asynchronous
+	 * methods, using an instance of {@link GlobalAsyncExceptionHandler}.</p>
+	 *
+	 * @return an instance of {@link GlobalAsyncExceptionHandler} for handling uncaught async exceptions
+	 */
 	@Override
 	@Bean
 	public AsyncUncaughtExceptionHandler getAsyncUncaughtExceptionHandler() {

src/main/java/com/beat/global/common/handler/GlobalAsyncExceptionHandler.java

@@ -11,6 +11,17 @@
 @Slf4j
 public class GlobalAsyncExceptionHandler implements AsyncUncaughtExceptionHandler {
 
+	/**
+	 * Handles uncaught exceptions thrown during asynchronous method execution.
+	 *
+	 * This method logs an error message with the method name and exception details. If the provided
+	 * parameters array is null, it logs that no parameters were provided; otherwise, it logs the string
+	 * representation of the parameters.
+	 *
+	 * @param ex the exception that occurred (non-null)
+	 * @param method the method where the exception was thrown (non-null)
+	 * @param params the parameters passed to the method; may be null
+	 */
 	@Override
 	public void handleUncaughtException(@NonNull Throwable ex, @NonNull Method method, @Nullable Object... params) {
 		if (params == null) {

src/main/java/com/beat/global/external/notification/slack/application/SlackClient.java

@@ -10,6 +10,14 @@
 @FeignClient(name = "slackClient", url = "${slack.webhook.url}")
 public interface SlackClient {
 
+	/**
+	 * Sends a JSON payload as a Slack message to the configured webhook.
+	 *
+	 * <p>This method posts the provided payload to the Slack webhook specified in the application properties.
+	 * The payload should contain key-value pairs representing the Slack message details.
+	 *
+	 * @param payload JSON payload containing details of the Slack message
+	 */
 	@PostMapping(consumes = MediaType.APPLICATION_JSON_VALUE)
 	void sendMessage(@RequestBody Map<String, String> payload);
 }

src/main/java/com/beat/global/external/notification/slack/application/SlackService.java

@@ -12,6 +12,13 @@ public class SlackService {
 
 	private final SlackClient slackClient;
 
+	/**
+	 * Sends a Slack message using the provided payload.
+	 *
+	 * This method forwards the message payload to the Slack client.
+	 *
+	 * @param payload a map containing key-value pairs representing the details of the Slack message
+	 */
 	public void sendMessage(Map<String, String> payload) {
 		slackClient.sendMessage(payload);
 	}

src/main/java/com/beat/global/external/notification/slack/event/MemberRegisteredEventListener.java

@@ -26,6 +26,15 @@ public class MemberRegisteredEventListener {
 	private final MemberUseCase memberUseCase;
 	private final SlackService slackService;
 
+	/**
+	 * Asynchronously sends a Slack notification when a new member registers.
+	 *
+	 * <p>This method is triggered after a transaction commits and builds a payload with a welcome
+	 * message that includes the current number of members and the new member's nickname. It then tries
+	 * to send this payload to Slack. If the message fails to send, a RuntimeException is thrown.
+	 *
+	 * @param event the member registration event containing details about the new member
+	 */
 	@Async("taskExecutor")
 	@TransactionalEventListener(phase = TransactionPhase.AFTER_COMMIT)
 	public void sendSlackNotification(MemberRegisteredEvent event) {