문제 발단
- image를 업로드하여 요청을 보내지 않으면 게시판에서
String index out of range오류가 발생했다.
Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.StringIndexOutOfBoundsException: String index out of range: -1] with root cause
- 예외코드 전문:
Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is java.lang.StringIndexOutOfBoundsException: String index out of range: -1] with root cause
java.lang.StringIndexOutOfBoundsException: String index out of range: -1
at java.base/java.lang.String.substring(String.java:1837) ~[na:na]
at com.growstory.global.aws.service.S3Uploader.uploadImageToS3(S3Uploader.java:29) ~[main/:na]
at com.growstory.domain.journal.service.JournalService.createJournal(JournalService.java:52) ~[main/:na]
at com.growstory.domain.journal.service.JournalService$$FastClassBySpringCGLIB$$157ba05f.invoke(<generated>) ~[main/:na]
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793) ~[spring-aop-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.29.jar:5.3.29]
at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:123) ~[spring-tx-5.3.29.jar:5.3.29]
at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:388) ~[spring-tx-5.3.29.jar:5.3.29]
at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:119) ~[spring-tx-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708) ~[spring-aop-5.3.29.jar:5.3.29]
at com.growstory.domain.journal.service.JournalService$$EnhancerBySpringCGLIB$$ca5b2ba4.createJournal(<generated>) ~[main/:na]
at com.growstory.domain.journal.controller.JournalController.postJournal(JournalController.java:46) ~[main/:na]
at com.growstory.domain.journal.controller.JournalController$$FastClassBySpringCGLIB$$22bfaea9.invoke(<generated>) ~[main/:na]
at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:218) ~[spring-core-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:793) ~[spring-aop-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:163) ~[spring-aop-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.29.jar:5.3.29]
at org.springframework.validation.beanvalidation.MethodValidationInterceptor.invoke(MethodValidationInterceptor.java:123) ~[spring-context-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.proceed(CglibAopProxy.java:763) ~[spring-aop-5.3.29.jar:5.3.29]
at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:708) ~[spring-aop-5.3.29.jar:5.3.29]
at com.growstory.domain.journal.controller.JournalController$$EnhancerBySpringCGLIB$$9c9e16a4.postJournal(<generated>) ~[main/:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:566) ~[na:na]
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:205) ~[spring-web-5.3.29.jar:5.3.29]
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:150) ~[spring-web-5.3.29.jar:5.3.29]
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117) ~[spring-webmvc-5.3.29.jar:5.3.29]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895) ~[spring-webmvc-5.3.29.jar:5.3.29]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808) ~[spring-webmvc-5.3.29.jar:5.3.29]
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.3.29.jar:5.3.29]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1072) ~[spring-webmvc-5.3.29.jar:5.3.29]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:965) ~[spring-webmvc-5.3.29.jar:5.3.29]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.29.jar:5.3.29]
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909) ~[spring-webmvc-5.3.29.jar:5.3.29]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:555) ~[tomcat-embed-core-9.0.79.jar:4.0.FR]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.29.jar:5.3.29]
at javax.servlet.http.HttpServlet.service(HttpServlet.java:623) ~[tomcat-embed-core-9.0.79.jar:4.0.FR]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:209) ~[tomcat-embed-core-9.0.79.jar:9.0.79]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) ~[tomcat-embed-core-9.0.79.jar:9.0.79]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51) ~[tomcat-embed-websocket-9.0.79.jar:9.0.79]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) ~[tomcat-embed-core-9.0.79.jar:9.0.79]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) ~[tomcat-embed-core-9.0.79.jar:9.0.79]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:111) ~[spring-web-5.3.29.jar:5.3.29]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) ~[tomcat-embed-core-9.0.79.jar:9.0.79]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) ~[tomcat-embed-core-9.0.79.jar:9.0.79]
at org.springframework.web.servlet.resource.ResourceUrlEncodingFilter.doFilter(ResourceUrlEncodingFilter.java:67) ~[spring-webmvc-5.3.29.jar:5.3.29]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:178) ~[tomcat-embed-core-9.0.79.jar:9.0.79]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:153) ~[tomcat-embed-core-9.0.79.jar:9.0.79]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:337) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.access.intercept.AuthorizationFilter.doFilter(AuthorizationFilter.java:96) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:122) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:116) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:126) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:81) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:109) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:149) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:223) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:217) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at com.growstory.global.auth.filter.JwtVerificationFilter.doFilterInternal(JwtVerificationFilter.java:42) ~[main/:na]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.29.jar:5.3.29]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:223) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.authentication.AbstractAuthenticationProcessingFilter.doFilter(AbstractAuthenticationProcessingFilter.java:217) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.oauth2.client.web.OAuth2AuthorizationRequestRedirectFilter.doFilterInternal(OAuth2AuthorizationRequestRedirectFilter.java:178) ~[spring-security-oauth2-client-5.7.10.jar:5.7.10]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.29.jar:5.3.29]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:103) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:89) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.web.filter.CorsFilter.doFilterInternal(CorsFilter.java:91) ~[spring-web-5.3.29.jar:5.3.29]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.29.jar:5.3.29]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:90) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:75) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.29.jar:5.3.29]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:112) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:82) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:55) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.29.jar:5.3.29]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.session.DisableEncodeUrlFilter.doFilterInternal(DisableEncodeUrlFilter.java:42) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117) ~[spring-web-5.3.29.jar:5.3.29]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:346) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:221) ~[spring-security-web-5.7.10.jar:5.7.10]
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:186) ~[spring-security-web-5.7.10.jar:5.7.10]문제 해결 과정
-
이미지 없는 게시판 하나를 post 요청하기 위해 이미지를 업로드하지 않고 POST 요청을 보냈더니 StringIndexOutOfBoundsException: String index out of range: -1 가 발생했다.
- 음수 인덱스에 접근, 유효 범위를 벗어난 인덱스에 접근, 빈 문자열에서 인덱스에 접근
-
오류가 발생한 엔드포인트 : Journal(일지) 게시판 등록과정
postJournal()메서드
-
실제 오류가 발생한 파트 : at com.growstory.global.aws.service.S3Uploader.uploadImageToS3(S3Uploader.java:29) ~[main/:na]
Image.getOriginalFilename에서 확장자를 추출할 때StringIndexOutOfBoundsException이 발생했기 때문에 다음을 의심할 수 있었다.
일지 등록 관련 서비스에서 null처리가 제대로 이루어지지 않았다.
public JournalDto.Response createJournal(Long leafId, JournalDto.Post postDto, MultipartFile image)메서드
하지만 분명히 image가 null로 넘어올 경우를 대비해서 null처리를 했었다. 저기서 잡히지 않은 이유가 뭘까?
디버깅을 해보았다. 이유는 곧바로 발견할 수 있었다.
원인 발견
null 처리가 안되는 이유가 있었다. 파일 업로드를 하지 않으면 이미지가 null로 들어오는 것이 아닌, filename만 비워져 있는 채로 역직렬화하게 된다. 따라서 서비스 단에서도 null처리를 건너뛰게 되는 것이다.
해결방법
-
org.springframework.web.multipart.MultipartFile에는isEmpty()라는 메소드가 존재한다.
MultipartFile 인터페이스의 isEmpty() 메소드는 업로드된 파일이 비어있는지 여부를 확인하는 데 사용됩니다. 이 메소드는 파일 업로드 요청에서 전송된 파일이 존재하지 않을 때 또는 파일의 크기가 0일 때 true를 반환하며, 그렇지 않은 경우에는 false를 반환합니다.
일반적으로 웹 어플리케이션에서 파일 업로드를 처리할 때, 클라이언트가 파일을 첨부하지 않은 경우 또는 파일의 크기가 0일 경우에 대한 예외 처리 또는 유효성 검사를 수행하는 데 사용됩니다. 이를 통해 불필요한 파일 처리나 오류를 방지할 수 있습니다. -
해당 조건식을 사용해준다.
단, 주의해야할 점은 null 처리 이후에도 위 사진처럼 다른 메서드가 연결될 경우 해당 메서드의 null 처리 여부를 확인해야 한다는 것이다.
-
이후 요청이 정상적으로 처리되었다. (Journal 로우는 생성되었지만 JournalImage는 생성되지 않음.)
다른 해결 방법
- 애초에 upload 메서드에 try~catch문으로 해당 예외를 잡는 방법이 있다.
소감
-
파일, 이미지 입출력에서
isEmpty()라는 메소드를 사용해야하는 이유를 알게되었다. null과""(빈 문자열)은 다른 개념임을 재확인 했다. -
null 처리를 항상 신경써야 함을 깨달았다.
숙제
- 예외가 발생했을 때 Controller에서 발생하지 않는 예외도 Http 응답 메시지로 보낼 수 있을까?
지금 특정 서비스단에서 잡힌 예외는@RestControllerAdvice에서 잡히지 않고 500상태코드만 반환한다.
9에서 0으로, 백엔드 개발블로그