新闻管理的条件查询、分页展示、新增、编辑功能
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2024-03-04 09:50:17
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新闻管理的条件查询、分页展示、新增、编辑功能
1.Type与News是一对多的关系,News与Tag是多对多的关系
Tag类中:
@ManyToMany(mappedBy = "tags")
private List<News> newsList=new ArrayList<>();
Type类中:
//指定type和news的关系
@OneToMany(mappedBy = "type")
private List<News> news=new ArrayList<>();
News类中:
@ManyToOne
private Type type;
@ManyToOne
private User user;
@ManyToMany(cascade = CascadeType.PERSIST) //级联
private List<Tag> tags=new ArrayList<>();
@Transient
private String tagIds;
2.新建vo包,在vo包下新建NewQuery类,这里的实体不进入数据库:
package com.zr0726.news.vo;
public class NewQuery {
private String title;
private Long typeId;
private boolean recommend;
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
public Long getTypeId() {
return typeId;
}
public void setTypeId(Long typeId) {
this.typeId = typeId;
}
public boolean isRecommend() {
return recommend;
}
public void setRecommend(boolean recommend) {
this.recommend = recommend;
}
@Override
public String toString() {
return "NewQuery{" +
"title='" + title + '\'' +
", typeId=" + typeId +
", recommend=" + recommend +
'}';
}
}
3.在NewRepository中:
package com.zr0726.news.dao;
import com.zr0726.news.po.News;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.jpa.repository.JpaRepository;
import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
import org.springframework.data.jpa.repository.Query;
import java.util.stream.Stream;
public interface NewRepository extends JpaRepository<News,Long> , JpaSpecificationExecutor<News> {
// @Query("select n from News n where n.title like ?1 or n.content like ?1")
// Page<News> findByQuery(String query, Pageable pageable);
}
4.在Service层新建NewService类:
package com.zr0726.news.service;
import com.zr0726.news.po.News;
import com.zr0726.news.vo.NewQuery;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
public interface NewService {
Page<News> listNew(Pageable pageable, NewQuery newQuery);
News saveNew(News news);
News getNew(Long id);
News updateNew(Long id,News news);
}
在NewServiceImpl中实现接口方法:
package com.zr0726.news.service.impl;
import com.zr0726.news.dao.NewRepository;
import com.zr0726.news.po.News;
import com.zr0726.news.service.NewService;
import com.zr0726.news.vo.NewQuery;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.jpa.domain.Specification;
import org.springframework.stereotype.Service;
import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Predicate;
import javax.persistence.criteria.Root;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
@Service
public class NewServiceImpl implements NewService {
@Autowired
private NewRepository newRepository;
//新闻管理中的列表(包含了查询)
@Override
public Page<News> listNew(Pageable pageable, NewQuery newQuery) {
return newRepository.findAll(new Specification<News>() {
@Override
public Predicate toPredicate(Root<News> root, CriteriaQuery<?> cq, CriteriaBuilder cb) {
List<Predicate> predicates=new ArrayList<>();
if(!"".equals(newQuery.getTitle())&&newQuery.getTitle()!=null){
predicates.add(cb.like(root.<String>get("title"),"%"+newQuery.getTitle()+"%"));
}
if(newQuery.getTypeId()!=null){
predicates.add(cb.equal(root.get("type").get("id"),newQuery.getTypeId()));
}
if(newQuery.isRecommend()){
predicates.add(cb.equal(root.get("recommend"),newQuery.isRecommend()));
}
cq.where(predicates.toArray(new Predicate[predicates.size()]));
return null;
}
},pageable);
}
@Override
public News saveNew(News news) {
if(news.getId()==null){
news.setCreateTime(new Date());
news.setUpdateTime(new Date());
}
return newRepository.save(news);
}
@Override
public News getNew(Long id) {
return newRepository.findById(id).orElse(null);
}
@Override
public News updateNew(Long id, News news) {
News news1 = newRepository.findById(id).orElse(null);
if(news1==null){
System.out.println("未获得更新对象");
}
BeanUtils.copyProperties(news,news1);
news1.setUpdateTime(new Date());
return newRepository.save(news1);
}
}
5.在TagService中增加接口:
List<Tag> listTag();
List<Tag> listTag(String ids);
在TagServiceImpl中实现:
@Override
public List<Tag> listTag() {
return tagRepository.findAll();
}
@Override
public List<Tag> listTag(String ids) {
return tagRepository.findAllById(convertToList(ids));
}
private List<Long> convertToList(String ids){
System.out.println("service接收id为:"+ids);
List<Long> list=new ArrayList<>();
if(!"".equals(ids) && ids!=null){
String[] idArray=ids.split(",");
for (int i=0;i<idArray.length;i++){
list.add(new Long(idArray[i]));
}
}
System.out.println("Service中处理完成后的id list:"+list);
return list;
}
在TypeService中增加接口:
List<Type> listType();
在TypeServiceImpl中实现:
@Override
public List<Type> listType() {
return typeRepository.findAll();
}
6.在controller层新建NewsController
package com.zr0726.news.web.admin;
import com.zr0726.news.po.News;
import com.zr0726.news.po.User;
import com.zr0726.news.service.NewService;
import com.zr0726.news.service.TagService;
import com.zr0726.news.service.TypeService;
import com.zr0726.news.vo.NewQuery;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.Sort;
import org.springframework.data.web.PageableDefault;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.mvc.support.RedirectAttributes;
import javax.servlet.http.HttpSession;
@Controller
@RequestMapping("/admin")
public class NewController {
private static final String INPUT="admin/news-input";
private static final String LIST="admin/news";
private static final String REDIRECT_LIST="redirect:/admin/news";
@Autowired
private NewService newService;
@Autowired
private TypeService typeService;
@Autowired
private TagService tagService;
@GetMapping("/news")
public String news(@PageableDefault(size=3,sort = {"updateTime"},direction = Sort.Direction.DESC)
Pageable pageable, NewQuery newQuery, Model model){
model.addAttribute("types",typeService.listType());
model.addAttribute("page",newService.listNew(pageable,newQuery));
return LIST;
}
@PostMapping("/news/search")
public String search(@PageableDefault(size=3,sort = {"updateTime"},direction = Sort.Direction.DESC)
Pageable pageable, NewQuery newQuery, Model model){
model.addAttribute("page",newService.listNew(pageable,newQuery));
return "admin/news::newsList";
}
public void setTypeAndTag(Model model){
model.addAttribute("types",typeService.listType());
model.addAttribute("tags",tagService.listTag());
}
@GetMapping("/news/input")
public String input(Model model){
// model.addAttribute("types",typeService.listType());
// model.addAttribute("tag",tagService.listTag());
setTypeAndTag(model);
model.addAttribute("news",new News());
return INPUT;
}
@GetMapping("/news/{id}/toUpdate")
public String toUpdate(@PathVariable Long id, Model model){
setTypeAndTag(model);
News news=newService.getNew(id);
news.init();
model.addAttribute("news",news);
return INPUT;
}
@PostMapping("/news/add")
public String post(News news, RedirectAttributes attributes, HttpSession session){
System.out.println("controller接收的news为:"+news);
news.setUser((User) session.getAttribute("user"));
news.setType(typeService.getType(news.getType().getId()));
news.setTags(tagService.listTag(news.getTagIds()));
News news1;
if(news.getId()==null){
news1=newService.saveNew(news);
}else {
news1=newService.updateNew(news.getId(),news);
}
if(news1==null){
attributes.addFlashAttribute("message","操作失败");
}else {
attributes.addFlashAttribute("message","操作成功");
}
return REDIRECT_LIST;
}
}
7.运行结果:
点击新闻列表:
搜索标签为计算机,标题中包含2的新闻:
点击新增按钮,跳转到新增页:
点击保存按钮,则保存为草稿:
点击编辑按钮,修改新闻信息,点击发布按钮:
可以看到,新闻的状态变为发布,标题也已经修改成功:
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