Spring Data Jpa分页显示

深碍√TFBOYSˉ_ 2022-03-26 03:06 255阅读 0赞

/**
    	 * 分页查询电影动态信息
    	 * @param page
    	 * @param pageSize
    	 * @return
    	 */ 
            @Override
    	public List<WebSiteInfo> list(WebSiteInfo webSiteInfo, Integer page, Integer pageSize) {
    		Pageable pageable=new PageRequest(page, pageSize,Sort.Direction.DESC,"publishDate");
    		Page<WebSiteInfo> pageWebSite=webSiteInfoRepository.findAll(new Specification<WebSiteInfo>() {
    			
    			@Override
    			public Predicate toPredicate(Root<WebSiteInfo> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
    				Predicate predicate=cb.conjunction();
    				if(webSiteInfo!=null){
    					if(StringUtil.isNotEmpty(webSiteInfo.getInfo())){
    						predicate.getExpressions().add(cb.like(root.get("info"), "%"+webSiteInfo.getInfo().trim()+"%"));
    					}
    				}
    				return predicate;
    			}
    		}, pageable);
    		return pageWebSite.getContent();
    	}
            /**
    	 * 获取总记录数
    	 * @return
    	 */
    	@Override
    	public Long getCount(WebSiteInfo webSiteInfo) {
    		Long count=webSiteInfoRepository.count(new Specification<WebSiteInfo>() {
    
    			@Override
    			public Predicate toPredicate(Root<WebSiteInfo> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
    				Predicate predicate=cb.conjunction();
    				if(webSiteInfo!=null){
    					if(StringUtil.isNotEmpty(webSiteInfo.getInfo())){
    						predicate.getExpressions().add(cb.like(root.get("info"), "%"+webSiteInfo.getInfo().trim()+"%"));
    					}
    				}
    				return predicate;
    			}
    		});
    		return count;
    	}

/**
    	 * 生成分页代码
    	 * @param targetUrl 目标地址
    	 * @param totalNum 总记录数
    	 * @param currentPage 当前页
    	 * @param pageSize 每页大小
    	 * @return
    	 */
    	public static String genPagination(String targetUrl,long totalNum,int currentPage,int pageSize){
    		long totalPage=totalNum%pageSize==0?totalNum/pageSize:totalNum/pageSize+1;
    		if(totalPage==0){
    			return "未查询到数据";
    		}else{
    			StringBuffer pageCode=new StringBuffer();
    			pageCode.append("<li><a href='"+targetUrl+"/1'>首页</a></li>");
    			if(currentPage>1){
    				pageCode.append("<li><a href='"+targetUrl+"/"+(currentPage-1)+"'>上一页</a></li>");			
    			}else{
    				pageCode.append("<li class='disabled'><a href='#'>上一页</a></li>");		
    			}
    			for(int i=currentPage-2;i<=currentPage+2;i++){
    				if(i<1||i>totalPage){
    					continue;
    				}
    				if(i==currentPage){
    					pageCode.append("<li class='active'><a href='"+targetUrl+"/"+i+"'>"+i+"</a></li>");	
    				}else{
    					pageCode.append("<li><a href='"+targetUrl+"/"+i+"'>"+i+"</a></li>");	
    				}
    			}
    			if(currentPage<totalPage){
    				pageCode.append("<li><a href='"+targetUrl+"/"+(currentPage+1)+"'>下一页</a></li>");		
    			}else{
    				pageCode.append("<li class='disabled'><a href='#'>下一页</a></li>");	
    			}
    			pageCode.append("<li><a href='"+targetUrl+"/"+totalPage+"'>尾页</a></li>");
    			return pageCode.toString();
    		}
    	}

/**
    	 * 分页查询 电影网站动态信息
    	 * @param page
    	 * @return
    	 * @throws Exception
    	 */
    	@RequestMapping("/list/{id}")
    	public ModelAndView list(@PathVariable(value="id",required=false)Integer page)throws Exception{
    		ModelAndView mav=new ModelAndView();
    		List<WebSiteInfo> webSiteInfoList=webSiteInfoService.list(null, page-1, 20);
    		Long total=webSiteInfoService.getCount(null);
    		mav.addObject("webSiteInfoList", webSiteInfoList);
    		mav.addObject("pageCode", PageUtil.genPagination("/webSiteInfo/list", total, page, 20));
    		mav.addObject("title", "电影网站动态信息列表");
    		mav.addObject("mainPage", "webSiteInfo/list");
    		mav.addObject("mainPageKey", "#f");
    		mav.setViewName("index");
    		return mav;
    	}