jQuery条件分页 代替离线查询（附代码）

importjavax.persistence.criteria.CriteriaBuilder;importjavax.persistence.criteria.CriteriaQuery;importjavax.persistence.

import javax.persistence.criteria.CriteriaBuilder;
import javax.persistence.criteria.CriteriaQuery;
import javax.persistence.criteria.Join;
import javax.persistence.criteria.Predicate;
import javax.persistence.criteria.Root;

import net.sf.json.JSONObject;
import net.sf.json.JsonConfig;

 @Action("courierAction_pageQuery")
 public String pageQuery() throws Exception {
 Pageable pageable = new PageRequest(page-1, rows);
 final String courierNum = model.getCourierNum();
 final String company = model.getCompany();
 final String type = model.getType();
 final Standard standard = model.getStandard();
 
 //相当于DetchedCriteria对象.通过specification封装过滤条件
 Specification<Courier> specification = new Specification<Courier>() {
 
 @Override
 public Predicate toPredicate(Root<Courier> root, CriteriaQuery<?> query, CriteriaBuilder cb) {
 //root：根实体 query：排序，封装条件 CriteriaBuilder：Predicate断言工厂，产生Predicate对象
 //添加过滤条件:添加快递员编号条件
 //p1:实体中属性 p2:条件
 List<Predicate> list = new ArrayList<>();
 if(StringUtils.isNotBlank(courierNum)){
 Predicate p1 = cb.equal(root.get("courierNum").as(String.class), courierNum);
 list.add(p1);
 }
 if(StringUtils.isNotBlank(company)){
 Predicate p2 = cb.equal(root.get("company").as(String.class), company);
 list.add(p2);
 }
 if(StringUtils.isNotBlank(type)){
 Predicate p3 = cb.equal(root.get("type").as(String.class), type);
 list.add(p3);
 }
 //sql : select * from T_COURIER t inner join t_Standard s on t.c_standard_id = s.c_id
// where s.c_name = '标准一（100公斤）';
 //JPQL: from Courier c inner join c.standard s where s.name = "";
 if(standard!=null && StringUtils.isNotBlank(standard.getName())){
 //返回关联对象
 Join<Object, Object> join = root.join("standard");
 Predicate p4 = cb.equal(join.get("name").as(String.class), standard.getName());
 list.add(p4);
 }
 if(list.size()==0){
 return null;
 }
 //list集合转为数组
 Predicate[] restrictions = new Predicate[list.size()];
 restrictions = list.toArray(restrictions);
 return cb.and(restrictions);
 }
 };
 Page<Courier> page = courierService.findAll(specification, pageable);
 
 Map<String, Object> map = new HashMap<>();
 map.put("total", page.getTotalElements());
 map.put("rows", page.getContent());
 
 //将fixedares集合属性排除掉，不转json
 JsonConfig jsonConfig = new JsonConfig();
 jsonConfig.setExcludes(new String[]{"fixedAreas"});
 
 String json = JSONObject.fromObject(map, jsonConfig).toString();
 
 ServletActionContext.getResponse().setContentType("text/json;charset=utf-8");
 ServletActionContext.getResponse().getWriter().write(json);
 return NONE;
 }
Dao:
public interface CourierDao extends JpaRepository<Courier, Integer>, JpaSpecificationExecutor<Courier> {

}

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jq 条件分页 离线查询 条件分页代替离线