LoginUser user = LoginUser.builder()
    .email("user@example.com")
    .nickname("user")
    .age(25)
    .build();

@Getter
@NoArgsConstructor
@AllArgsConstructor
@Builder
public class LoginUser {
    private String email;
    private String nickname;
    private int age;
}

LoginUser user = LoginUser.builder()
    .email("user@example.com")
    .nickname("Kobe")
    .age(28)
    .build();

public class LoginUser {
    public static class LoginUserBuilder {
        private String email;
        private String nickname;
        private int age;
        
        public LoginUserBuilder email(String email) {
            this.email = email;
            return this;
        }
        
        public LoginUser build() {
            return new LoginUser(email, nickname, age);
        }
    }
}

@Builder
public class LoginUser {
    private String email;
    
    @Builder.Default
    private String role = "USER"; // 기본값 설정
}