localhost8080 에서 json 경로만 500 서버 오류가 납니다

[질문 템플릿]
1. 강의 내용과 관련된 질문인가요? (예/아니오)
2. 인프런의 질문 게시판과 자주 하는 질문에 없는 내용인가요? (예/아니오)
3. 질문 잘하기 메뉴얼을 읽어보셨나요? (예/아니오)

[질문 내용]
영한님 수업 잘 따라오면서 나머지 강의들은 잘 프로그램이 작동했는데 HTTP요청 데이터 -API 메시지 바디 -JSON강의 실습이후 json요청 페이지에서만 오류가 뜨고 localhost8080에서는 백지 화면이 뜹니다 제가 무지해 혹시 오류가 따로 있을거같아 컴파일보드 메모장으로 첨부해봅니다..

오후 11:15:43: Executing ':ServletApplication.main()'...

> Task :compileJava UP-TO-DATE
> Task :processResources UP-TO-DATE
> Task :classes UP-TO-DATE

> Task :ServletApplication.main()

  .   ____          _            __ _ _
 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )
  '  |____| .__|_| |_|_| |_\__, | / / / /
 =========|_|==============|___/=/_/_/_/
 :: Spring Boot ::                (v3.2.2)

2024-01-22T23:15:44.017+09:00  INFO 4424 --- [           main] hello.servlet.ServletApplication         : Starting ServletApplication using Java 21.0.1 with PID 4424 (C:\Users\�赿��\Desktop\Spring-mvc\servlet\build\classes\java\main started by �赿�� in C:\Users\�赿��\Desktop\Spring-mvc\servlet)
2024-01-22T23:15:44.018+09:00  INFO 4424 --- [           main] hello.servlet.ServletApplication         : No active profile set, falling back to 1 default profile: "default"
2024-01-22T23:15:44.667+09:00  INFO 4424 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port 8080 (http)
2024-01-22T23:15:44.676+09:00  INFO 4424 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]
2024-01-22T23:15:44.677+09:00  INFO 4424 --- [           main] o.apache.catalina.core.StandardEngine    : Starting Servlet engine: [Apache Tomcat/10.1.18]
2024-01-22T23:15:44.711+09:00  INFO 4424 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext
2024-01-22T23:15:44.712+09:00  INFO 4424 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 652 ms
2024-01-22T23:15:44.787+09:00  INFO 4424 --- [           main] o.s.b.a.w.s.WelcomePageHandlerMapping    : Adding welcome page: ServletContext resource [/index.html]
2024-01-22T23:15:44.968+09:00  INFO 4424 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat started on port 8080 (http) with context path ''
2024-01-22T23:15:44.973+09:00  INFO 4424 --- [           main] hello.servlet.ServletApplication         : Started ServletApplication in 1.2 seconds (process running for 1.426)
2024-01-22T23:15:49.563+09:00 DEBUG 4424 --- [nio-8080-exec-1] o.a.coyote.http11.Http11InputBuffer      : Before fill(): parsingHeader: [true], parsingRequestLine: [true], parsingRequestLinePhase: [0], parsingRequestLineStart: [0], byteBuffer.position(): [0], byteBuffer.limit(): [0], end: [0]
2024-01-22T23:15:49.564+09:00 DEBUG 4424 --- [nio-8080-exec-1] o.a.coyote.http11.Http11InputBuffer      : Received [GET / HTTP/1.1
Host: localhost:8080
Connection: keep-alive
Cache-Control: max-age=0
sec-ch-ua: "Not_A Brand";v="8", "Chromium";v="120", "Google Chrome";v="120"
sec-ch-ua-mobile: ?0
sec-ch-ua-platform: "Windows"
Upgrade-Insecure-Requests: 1
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.7
Sec-Fetch-Site: none
Sec-Fetch-Mode: navigate
Sec-Fetch-User: ?1
Sec-Fetch-Dest: document
Accept-Encoding: gzip, deflate, br
Accept-Language: ko-KR,ko;q=0.9,en-US;q=0.8,en;q=0.7

]
[��ü �Ķ���� ��ȸ] - start
[��ü �Ķ���� ��ȸ] - end
2024-01-22T23:15:49.582+09:00 DEBUG 4424 --- [nio-8080-exec-1] o.a.coyote.http11.Http11InputBuffer      : Before fill(): parsingHeader: [true], parsingRequestLine: [true], parsingRequestLinePhase: [0], parsingRequestLineStart: [0], byteBuffer.position(): [0], byteBuffer.limit(): [0], end: [704]
2024-01-22T23:15:49.582+09:00 DEBUG 4424 --- [nio-8080-exec-1] o.a.coyote.http11.Http11InputBuffer      : Received []
2024-01-22T23:15:49.583+09:00 DEBUG 4424 --- [nio-8080-exec-1] o.apache.coyote.http11.Http11Processor   : Socket: [org.apache.tomcat.util.net.NioEndpoint$NioSocketWrapper@41b5971e:org.apache.tomcat.util.net.NioChannel@8c53d83:java.nio.channels.SocketChannel[connected local=/[0:0:0:0:0:0:0:1]:8080 remote=/[0:0:0:0:0:0:0:1]:51861]], Status in: [OPEN_READ], State out: [OPEN]
2024-01-22T23:15:49.598+09:00 DEBUG 4424 --- [nio-8080-exec-3] o.a.coyote.http11.Http11InputBuffer      : Before fill(): parsingHeader: [true], parsingRequestLine: [true], parsingRequestLinePhase: [0], parsingRequestLineStart: [0], byteBuffer.position(): [0], byteBuffer.limit(): [0], end: [704]
2024-01-22T23:15:49.599+09:00 DEBUG 4424 --- [nio-8080-exec-3] o.a.coyote.http11.Http11InputBuffer      : Received [GET /favicon.ico HTTP/1.1
Host: localhost:8080
Connection: keep-alive
sec-ch-ua: "Not_A Brand";v="8", "Chromium";v="120", "Google Chrome";v="120"
sec-ch-ua-mobile: ?0
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36
sec-ch-ua-platform: "Windows"
Accept: image/avif,image/webp,image/apng,image/svg+xml,image/*,*/*;q=0.8
Sec-Fetch-Site: same-origin
Sec-Fetch-Mode: no-cors
Sec-Fetch-Dest: image
Referer: http://localhost:8080/
Accept-Encoding: gzip, deflate, br
Accept-Language: ko-KR,ko;q=0.9,en-US;q=0.8,en;q=0.7

]
[��ü �Ķ���� ��ȸ] - start
[��ü �Ķ���� ��ȸ] - end
2024-01-22T23:15:49.601+09:00 DEBUG 4424 --- [nio-8080-exec-3] o.a.coyote.http11.Http11InputBuffer      : Before fill(): parsingHeader: [true], parsingRequestLine: [true], parsingRequestLinePhase: [0], parsingRequestLineStart: [0], byteBuffer.position(): [0], byteBuffer.limit(): [0], end: [604]
2024-01-22T23:15:49.601+09:00 DEBUG 4424 --- [nio-8080-exec-3] o.a.coyote.http11.Http11InputBuffer      : Received []
2024-01-22T23:15:49.601+09:00 DEBUG 4424 --- [nio-8080-exec-3] o.apache.coyote.http11.Http11Processor   : Socket: [org.apache.tomcat.util.net.NioEndpoint$NioSocketWrapper@41b5971e:org.apache.tomcat.util.net.NioChannel@8c53d83:java.nio.channels.SocketChannel[connected local=/[0:0:0:0:0:0:0:1]:8080 remote=/[0:0:0:0:0:0:0:1]:51861]], Status in: [OPEN_READ], State out: [OPEN]