Spring data JPA先排序再分页。

//工具类，增删改查等等
package com.yunqing.service.impl;
 
import java.util.Map;
 
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.PageRequest;
import org.springframework.data.domain.Pageable;
import org.springframework.data.domain.Sort;
import org.springframework.data.jpa.domain.Specification;
import org.springframework.data.jpa.repository.JpaSpecificationExecutor;
import org.springframework.data.repository.PagingAndSortingRepository;
import org.springframework.transaction.annotation.Transactional;
import org.springside.modules.persistence.DynamicSpecifications;
import org.springside.modules.persistence.SearchFilter;
 
public class RootServiceImpl<T> {
 
    @Autowired
    PagingAndSortingRepository<T, String> pasr;
 
    @Autowired
    JpaSpecificationExecutor<T> jpas;
 
    /**
     * 根据条件查询
     * @param paramMap
     * @param page
     * @param rows
     * @param clazz
     * @return
     */
    @Transactional(readOnly=true)
    public Page<T> findAllByParam(Map<String, Object> paramMap, int page,int rows,Class<T> clazz) {
        Map<String, SearchFilter> filters = SearchFilter.parse(paramMap);
        Specification<T> spec = DynamicSpecifications.bySearchFilter(filters.values(),clazz);
        Pageable pageable = new PageRequest(page, rows);
        Page<T> resultPage = jpas.findAll(spec,pageable);
        return resultPage;
    }
    /**
     * 根据ID查询
     * @param id
     * @return
     */
    //@Transactional(readOnly=true)
    public T findEntityById(String id){
        T t=pasr.findOne(id);
        return t;
    }
    /**
     * 查询全部
     * @return
     */
    @Transactional(readOnly=true)
    public Iterable<T> findAllEntity(){
        Iterable<T> list=pasr.findAll();
        return list;
    }
 
    /**
     * 删除
     * @param id
     */
    @Transactional
    public void deleteEntityById(String id){
        pasr.delete(id);
    }
    /**
     * 删除
     * @param t
     */
    @Transactional
    public void deleteEntity(T t){
        pasr.delete(t);
    }
    /**
     * 删除多个
     * @param ids
     */
    @Transactional
    public void deleteEntity(Iterable<T> iterable){
        pasr.delete(iterable);
    }
 
    /**
     * 保存
     * @param t
     */
    @Transactional
    public void save(T t){
        pasr.save(t);
    }
    /**
     * 保存
     * @param tList
     */
    @Transactional
    public void save(Iterable<T> tList){
        pasr.save(tList);
    }
    /**
     * 删除多个/单个
     * <b>deleteEntity</b>
     * <p><b>详细说明：</b></p>
     *
     *@param ids
     */
    @Transactional
    public void deleteEntity(String ids){
        if(ids!=null&&!"".equals(ids)){
            if(ids.contains(":")){
                String[] idArr = ids.split(":");
                for(String id : idArr){
                    deleteEntityById(id);
                }
            }else{
                    deleteEntityById(ids);
            }
        }
    }
    @Transactional
    public Page<T> findAllByParam(Map<String, Object> paramMap, int page,int rows,Class<T> clazz,Sort sort) {
        Map<String, SearchFilter> filters = SearchFilter.parse(paramMap);
        Specification<T> spec = DynamicSpecifications.bySearchFilter(filters.values(),clazz);
        Pageable pageable = new PageRequest(page, rows,sort);
        Page<T> resultPage = jpas.findAll(spec,pageable);
        return resultPage;
    }
}

service层

package com.yunqing.service.impl;
 
import java.util.Map;
 
import javax.transaction.Transactional;
 
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Sort;
import org.springframework.stereotype.Service;
import com.tideway.live.vo.Student;
import com.tideway.utils.FileUtil;
 
@Service("/studentService")
public class StudentServiceImpl extends RootServiceImpl<Student>{
//查询所有的学生，先排序后查询！！！！！！！！！！！！sort是排序条件参数，在controller层给参数赋值
    public Page<Student> queryStudentList(Map<String, Object> paramMap, int page, int rows,Sort sort) {
        // TODO Auto-generated method stub
        //Page<Student> esultPage = findAllByParam(paramMap, page, rows,Student.class);
        Page<Student> esultPage=findAllByParam(paramMap, page, rows, Student.class,sort);
        return esultPage;
    }
}

controller层

package com.yunqing.controller;
 
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.net.URLDecoder;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
 
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
 
import org.apache.commons.collections4.map.HashedMap;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.domain.Page;
import org.springframework.data.domain.Sort;
import org.springframework.data.domain.Sort.Direction;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.WebDataBinder;
import org.springframework.web.bind.annotation.InitBinder;
import org.springframework.web.bind.annotation.ModelAttribute;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.multipart.MultipartFile;
 
import com.tideway.live.service.impl.StudentServiceImpl;
import com.tideway.live.vo.Student;
import com.tideway.utils.FileUtil;
 
@Controller
@RequestMapping("/student")
public class StudentController extends BaseController{
 
    @InitBinder("student")
    public void initBinder(WebDataBinder binder) {
            binder.setFieldDefaultPrefix("student.");
    }
 
    @Autowired
    private StudentServiceImpl studentService;
 
    /**
     * 获取学员列表
     * @param request
     * @param response
     * @param student
     */
    @RequestMapping("/queryStudentList")
    public void queryStudentList(HttpServletRequest request,HttpServletResponse response,@ModelAttribute("student") Student student){
        Map<String, Object> paramMap = new HashedMap<String, Object>();
        if(student.getName()!=null&&!"".equals(student.getName())){
            paramMap.put("LIKE_name", student.getName());
        }
        //直接创建sort对象，通过排序方法和属性名
        Sort sort=new Sort(Direction.DESC,"createTime");//createTime是学生的录入时间，这样展示的时候就会按录入时间先排序再分页展示。
        //Page<Student> page  = studentService.queryStudentList(paramMap,this.getPage(request), this.getRows(request));
        Page<Student> page  = studentService.queryStudentList(paramMap, this.getPage(request), this.getRows(request),sort);
        List<Student> list = page.getContent();
        Map<String, Object> json = new HashMap<String, Object>();
        json.put("total",page.getTotalElements());
        json.put("rows",list);
        returnJson(response,json);
    }
}

也可以在service层搞定，还可以实现先多条件排序在分页。

public Page<SpecialguardInfo> findAllByParam(Map<String, Object> paramMap, int page, int rows) {
        // 先根据状态倒序排列，再根据创建时间倒序排序，再分页。
        List<Order> orders=new ArrayList<Sort.Order>();
        orders.add(new Order(Direction.DESC, "_state"));
        orders.add(new Order(Direction.DESC, "createtime"));
        //Sort sort = new Sort(Sort.Direction.DESC,"createtime");
        Page<SpecialguardInfo> page1=findAllByParam(paramMap, page, rows, SpecialguardInfo.class, new Sort(orders));//注意参数要修改成这样
        return page1;
    }

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