为了适应前端的列表动态加载,添加了getNewsByRange及其相关内容。

This commit is contained in:
高子兴 2024-07-04 12:20:04 +08:00
parent 9de8c77764
commit e66695cbff
3 changed files with 61 additions and 10 deletions

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@ -1,6 +1,7 @@
package org.cmh.backend.NewsManagement.controller; package org.cmh.backend.NewsManagement.controller;
import jakarta.persistence.EntityNotFoundException; import jakarta.persistence.EntityNotFoundException;
import org.cmh.backend.NewsManagement.dto.GetNewsListResponse;
import org.cmh.backend.NewsManagement.dto.MessageResponse; import org.cmh.backend.NewsManagement.dto.MessageResponse;
import org.cmh.backend.NewsManagement.dto.NewsRequest; import org.cmh.backend.NewsManagement.dto.NewsRequest;
import org.cmh.backend.NewsManagement.model.News; import org.cmh.backend.NewsManagement.model.News;
@ -8,7 +9,6 @@ import org.cmh.backend.NewsManagement.service.NewsService;
import org.cmh.backend.Utils.JwtVerify; import org.cmh.backend.Utils.JwtVerify;
import org.springframework.beans.factory.annotation.Autowired; import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.dao.DataIntegrityViolationException; import org.springframework.dao.DataIntegrityViolationException;
import org.springframework.data.domain.Page;
import org.springframework.http.HttpStatus; import org.springframework.http.HttpStatus;
import org.springframework.http.ResponseEntity; import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.*; import org.springframework.web.bind.annotation.*;
@ -20,8 +20,13 @@ public class NewsController {
private NewsService newsService; private NewsService newsService;
@GetMapping @GetMapping
public ResponseEntity<Page<News>> getNewsPage(@RequestParam Integer pageNo, @RequestParam Integer pageSize) { @JwtVerify
return new ResponseEntity<>(newsService.getNewsByPage(pageNo, pageSize), HttpStatus.OK); public ResponseEntity<GetNewsListResponse> getNewsByRange(@RequestParam Integer start, @RequestParam Integer end, @RequestParam String token) {
if (start >= end) {
return new ResponseEntity<>(HttpStatus.BAD_REQUEST);
}
long newsCount = newsService.getNewsCount();
return new ResponseEntity<>(new GetNewsListResponse(newsCount, newsService.getNewsByRange(start, end)), HttpStatus.OK);
} }
@GetMapping("/{id}") @GetMapping("/{id}")

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@ -0,0 +1,17 @@
package org.cmh.backend.NewsManagement.dto;
import lombok.AllArgsConstructor;
import lombok.Getter;
import lombok.Setter;
import org.cmh.backend.NewsManagement.model.News;
import java.util.List;
@Getter
@Setter
@AllArgsConstructor
public class GetNewsListResponse {
Long newsCount;
List<News> newsList;
}

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@ -10,22 +10,47 @@ import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable; import org.springframework.data.domain.Pageable;
import org.springframework.stereotype.Service; import org.springframework.stereotype.Service;
import java.util.ArrayList;
import java.util.List;
@Service @Service
public class NewsService { public class NewsService {
@Autowired @Autowired
private NewsRepository newsRepository; private NewsRepository newsRepository;
public Page<News> getNewsByPage(int pageNo, int pageSize) { public List<News> getNewsByRange(int start, int end) {
if (pageNo < 1) { if (start < 0 || end <= start) {
pageNo = 1; throw new IllegalArgumentException("Invalid start or end range");
} }
if (pageSize < 1) {
pageSize = 10; int pageSize = end - start; // 计算每页的大小
int startPageNumber = start / pageSize; // 计算起始页码
int endPageNumber = (end - 1) / pageSize; // 计算结束页码
List<News> result = new ArrayList<>();
for (int pageNumber = startPageNumber; pageNumber <= endPageNumber; pageNumber++) {
Pageable pageable = PageRequest.of(pageNumber, pageSize);
Page<News> newsPage = newsRepository.findAllByOrderByIdDesc(pageable);
if (newsPage.hasContent()) {
result.addAll(newsPage.getContent());
} else {
break; // 如果没有更多内容提前退出
}
} }
Pageable pageable = PageRequest.of(pageNo - 1, pageSize);
return newsRepository.findAllByOrderByIdDesc(pageable); int startIndex = start % pageSize;
int endIndex = startIndex + (end - start);
if (endIndex > result.size()) {
endIndex = result.size();
}
return result.subList(startIndex, endIndex);
} }
public void createNews(NewsRequest request) { public void createNews(NewsRequest request) {
News news = new News(); News news = new News();
news.setTitle(request.getTitle()); news.setTitle(request.getTitle());
@ -61,4 +86,8 @@ public class NewsService {
} }
return newsRepository.findById(id).orElse(null); return newsRepository.findById(id).orElse(null);
} }
public long getNewsCount() {
return newsRepository.count();
}
} }