[스프링] 게시판 페이징 오류 도와주세요ㅠㅠ

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[오류페이지]HTTP 상태 500 – 내부 서버 오류타입 예외 보고메시지 Request processing failed; nested exception is java.lang.NullPointerException설명 서버가, 해당 요청을 충족시키지 못하게 하는 예기치 않은 조건을 맞닥뜨렸습니다.예외org.springframework.web.util.NestedServletException: Request processing failed; nested exception is java.lang.NullPointerException org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:894) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778) javax.servlet.http.HttpServlet.service(HttpServlet.java:634) javax.servlet.http.HttpServlet.service(HttpServlet.java:741) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) 근본 원인 (root cause)java.lang.NullPointerException com.book.model.PageMakerVO.calcData(PageMakerVO.java:22) com.book.model.PageMakerVO.setTotalCount(PageMakerVO.java:71) com.book.controller.NoticeController.getList(NoticeController.java:42) java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) java.base/java.lang.reflect.Method.invoke(Method.java:566) org.springframework.web.method.support.InvocableHandlerMethod.invoke(InvocableHandlerMethod.java:213) org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:126) org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:96) org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:617) org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:578) org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:80) org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:923) org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:852) org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:882) org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:778) javax.servlet.http.HttpServlet.service(HttpServlet.java:634) javax.servlet.http.HttpServlet.service(HttpServlet.java:741) org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:88) org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:76) 비고 근본 원인(root cause)의 풀 스택 트레이스를, 서버 로그들에서 확인할 수 있습니다.Apache Tomcat/9.0.22 package com.book.controller; import java.util.List; import javax.inject.Inject; import org.springframework.stereotype.Controller; import org.springframework.ui.Model; import org.springframework.web.bind.annotation.ModelAttribute; import org.springframework.web.bind.annotation.RequestMapping; import org.springframework.web.bind.annotation.RequestMethod; import org.springframework.web.bind.annotation.RequestParam; import org.springframework.web.servlet.ModelAndView; import com.book.model.NoticeVO; import com.book.model.PageMakerVO; import com.book.model.PagingVO; import com.book.model.SearchPagingVO; import com.book.service.NoticeService; @Controller @RequestMapping("/notice/*") public class NoticeController { @Inject NoticeService service; //공지사항 목록 @RequestMapping(value = "/list", method = RequestMethod.GET) public void getList(@ModelAttribute("pagingVO") PagingVO pagingVO, Model model) throws Exception { System.out.println("get NoticeList"); List list =null; System.out.println("get NoticeList2"); list = service.list(pagingVO); System.out.println("get NoticeList3"); // 게시글 총 수 PageMakerVO pageMakerVO = new PageMakerVO(); System.out.println("get NoticeList4"); pageMakerVO.setTotalCount(service.count()); System.out.println("get NoticeList5"); model.addAttribute("pageMakerVO", pageMakerVO); System.out.println("get NoticeList6"); model.addAttribute("list",list); } //공지사항 조회 @RequestMapping(value = "/view", method = RequestMethod.GET) public void getView(@RequestParam("notice_id") int notice_id, Model model) throws Exception{ NoticeVO vo = service.view(notice_id); model.addAttribute("view", vo); } //공지사항 작성 (GET) @RequestMapping(value = "/write", method = RequestMethod.GET) public void getWirte() throws Exception{ } //공지사항 작성 (POST) @RequestMapping(value = "/write", method =RequestMethod.POST) public String posttWirte(NoticeVO vo) throws Exception{ service.write(vo); return "redirect:/notice/list"; } //공지사항 수정 (GET) @RequestMapping(value = "/modify", method = RequestMethod.GET) public void getModify(@RequestParam("notice_id") int notice_id, Model model) throws Exception { NoticeVO vo = service.view(notice_id); model.addAttribute("view", vo); } //공지사항 수정 (POST) @RequestMapping(value = "/modify", method = RequestMethod.POST) public String postModify(NoticeVO vo) throws Exception{ service.modify(vo); //수정 return "redirect:/notice/view?notice_id=" + vo.getNotice_id(); } //공지사항 삭제 @RequestMapping(value = "/delete", method = RequestMethod.GET) public String getDelete(@RequestParam("notice_id") int notice_id) throws Exception{ service.delete(notice_id); return "redirect:/notice/list"; } }package com.book.dao; import java.util.List; import com.book.model.NoticeVO; import com.book.model.PagingVO; public interface NoticeDAO { //공지사항 목록 public List list(PagingVO PagingVO) throws Exception; //공지사항 조회 public NoticeVO view(int notice_id) throws Exception; //공지사항 작성 public void write(NoticeVO vo) throws Exception; //공지사항 수정 public void modify(NoticeVO vo) throws Exception; //공지사항 삭제 public void delete(int notice_id) throws Exception; //공지사항 총 개수 count public int count() throws Exception; } package com.book.dao; package com.book.dao; import java.util.List; import javax.inject.Inject; import org.apache.ibatis.session.SqlSession; import org.springframework.stereotype.Repository; import com.book.model.NoticeVO; import com.book.model.PagingVO; @Repository public class NoticeDAOImpl implements NoticeDAO { @Inject private SqlSession sql; private static String namespace="com.book.mappers.noticeMapper"; //공지사항 목록 @Override public List list(PagingVO PagingVO) throws Exception { return sql.selectList(namespace+".list"); } //공지사항 조회 @Override public NoticeVO view(int notice_id) throws Exception { return sql.selectOne(namespace+".view", notice_id); } //공지사항 작성 @Override public void write(NoticeVO vo) throws Exception { sql.insert(namespace+".write", vo); } //공지사항 수정 @Override public void modify(NoticeVO vo) throws Exception { sql.update(namespace+".modify", vo); } //공지사항 삭제 @Override public void delete(int notice_id) throws Exception { sql.delete(namespace + ".delete", notice_id); } //공지사항 총 개수 @Override public int count() throws Exception { // TODO Auto-generated method stub return sql.selectOne(namespace + ".count"); } package com.book.service; import java.util.List; import com.book.model.NoticeVO; import com.book.model.PagingVO; public interface NoticeService { //공지사항 목록 public List list(PagingVO PagingVO) throws Exception; //공지사항 작성 public void write(NoticeVO vo) throws Exception; //공지사항 조회 public NoticeVO view(int notice_id) throws Exception; //공지사항 수정 public void modify(NoticeVO vo) throws Exception; //공지사항 삭제 public void delete(int notice_id) throws Exception; //공지사항 총 개수 public int count() throws Exception; } } package com.book.service; import java.util.List; import javax.inject.Inject; import org.springframework.stereotype.Service; import org.springframework.transaction.annotation.Isolation; import org.springframework.transaction.annotation.Transactional; import com.book.dao.NoticeDAO; import com.book.model.NoticeVO; import com.book.model.PagingVO; @Service public class NoticeServiceImpl implements NoticeService { @Inject private NoticeDAO dao; //공지사항 목록 @Override public List list(PagingVO PagingVO) throws Exception { return dao.list(PagingVO); } //공지사항 작성 @Override public void write(NoticeVO vo) throws Exception { dao.write(vo); } //공지사항 수정 @Override public void modify(NoticeVO vo) throws Exception { dao.modify(vo); } //공지사항 삭제 @Override public void delete(int notice_id) throws Exception { dao.delete(notice_id); } //공지사항 조회 @Override public NoticeVO view(int notice_id) throws Exception { //하나의 데이터를 읽어서 리턴 return dao.view(notice_id); } //공지사항 총 개수 @Override public int count() throws Exception { return dao.count(); } } insert into boddarinotice (notice_id,notice_title,notice_content,user_id) values(boddarinotice_seq.nextval, #{notice_title},#{notice_content},#{user_id}) update boddarinotice set notice_title = #{notice_title}, notice_content = #{notice_content}, user_id = #{user_id} where notice_id = #{notice_id} delete from boddarinotice where notice_id= #{notice_id} //공지사항 조회 @Override public NoticeVO view(int notice_id) throws Exception { return sql.selectOne(namespace+".view", notice_id); } //공지사항 작성 @Override public void write(NoticeVO vo) throws Exception { sql.insert(namespace+".write", vo); } //공지사항 수정 @Override public void modify(NoticeVO vo) throws Exception { sql.update(namespace+".modify", vo); } //공지사항 삭제 @Override public void delete(int notice_id) throws Exception { sql.delete(namespace + ".delete", notice_id); } //공지사항 총 개수 @Override public int count() throws Exception { // TODO Auto-generated method stub return sql.selectOne(namespace + ".count"); } } 페이징 package com.book.model; public class PagingVO { // 시작값과 끝값 private int page; private int perPageNum; // 한 페이지에 나올 게시글 수 private int rowStart; // 한 페이지 시작 게시글 private int rowEnd; // 한 페이지 끝 게시글 public PagingVO() { this.page = 1; this.perPageNum = 10; } public int getPage() { return page; } public void setPage(int page) { if (page <= 0) { this.page = 1; return; } this.page = page; } public int getPerPageNum() { return perPageNum; } public void setPerPageNum(int perPageNum) { if (perPageNum <= 0 || perPageNum > 100) { this.perPageNum = 10; return; } this.perPageNum = perPageNum; } public int getRowStart() { rowStart = ((page - 1) * perPageNum) + 1; return rowStart; } public void setRowStart(int rowStart) { this.rowStart = rowStart; } public int getRowEnd() { rowEnd = rowStart + perPageNum - 1; return rowEnd; } public void setRowEnd(int rowEnd) { this.rowEnd = rowEnd; } public int getPageStart() { return (this.page - 1) * perPageNum; } @Override public String toString() { return "PagingVO [page=" + page + ", perPageNum=" + perPageNum + "" + ", rowStart=" + getRowStart() + ", rowEnd=" + getRowEnd() + "]"; } } package com.book.model; import java.io.UnsupportedEncodingException; import java.net.URLEncoder; import org.springframework.web.util.UriComponents; import org.springframework.web.util.UriComponentsBuilder; public class PageMakerVO { // 페이지 블럭 처리 private int totalCount; // 게시물 총 수 private int startPage; // 현재 페이지 시작 번호 (1, 11, 21 등) private int endPage; // 현재 페이지 끝 번호 (10, 20, 30 등) private boolean prev; // 이전 페이지로 이동하는 링크 존재 여부 private boolean next; // 다음 페이지로 이동하는 링크 존재 여부 private int displayPageNum = 10; private PagingVO pVO; // PagingVO DTO public void calcData() { endPage = (int) (Math.ceil(pVO.getPage() / (double)displayPageNum) * displayPageNum); startPage = (endPage - displayPageNum) + 1; int tempEndPage = (int) (Math.ceil(totalCount / (double)pVO.getPerPageNum())); if (endPage > tempEndPage) { endPage = tempEndPage; } prev = startPage == 1 ? false : true; next = endPage * pVO.getPerPageNum() >= totalCount ? false : true; } // perPageNum 파라미터가 주소창에 뜨도록 public String makeQuery(int page) { UriComponents uriComponents = UriComponentsBuilder.newInstance() .queryParam("page", page) .queryParam("perPageNum", pVO.getPerPageNum()) .build(); return uriComponents.toUriString(); } // searchType과 keyword 파라미터가 주소창에 뜨도록 public String makeSearch(int page) { UriComponents uriComponents = UriComponentsBuilder.newInstance() .queryParam("page", page) .queryParam("perPageNum", pVO.getPerPageNum()) .queryParam("searchType", ((SearchPagingVO)pVO).getSearchType()) .queryParam("keyword", encoding(((SearchPagingVO)pVO).getKeyword())) .build(); return uriComponents.toUriString(); } private String encoding(String keyword) { if(keyword == null || keyword.trim().length() == 0) { return ""; } try { return URLEncoder.encode(keyword, "UTF-8"); } catch(UnsupportedEncodingException e) { return ""; } } public int getTotalCount() { return totalCount; } public void setTotalCount(int totalCount) { this.totalCount = totalCount; calcData(); } public int getStartPage() { return startPage; } public void setStartPage(int startPage) { this.startPage = startPage; } public int getEndPage() { return endPage; } public void setEndPage(int endPage) { this.endPage = endPage; } public boolean isPrev() { return prev; } public void setPrev(boolean prev) { this.prev = prev; } public boolean isNext() { return next; } public void setNext(boolean next) { this.next = next; } public int getDisplayPageNum() { return displayPageNum; } public void setDisplayPageNum(int displayPageNum) { this.displayPageNum = displayPageNum; } public PagingVO getpVO() { return pVO; } public void setpVO(PagingVO pVO) { this.pVO = pVO; } }

워르송 · Answer

음 .. 다른분들 보실수잇게 전체적인 코드말고 어디부분이 에러있는지 적어주시면 더 좋은답변 받을수있지않을까 싶습니다.. 예를들어 페이징 자체가 생성이 안된다던지 페이징 갯수가 안맞는다던지 이런식으로여

htofu · Answer

PageMakerVO 에 정의된 int 변수도 초기화를 시켜주세요.

[스프링] 게시판 페이징 오류 도와주세요ㅠㅠ

2개의 답변

#nullpointerexception 목록