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只是一个简单需求：  查询所有部门id 属于  idList 的数据

 Page<WorkWeight> page = workWeightRepository.findAll(new Specification<WorkWeight>() {@Overridepublic Predicate toPredicate(Root<WorkWeight> root, CriteriaQuery<?> query, CriteriaBuilder cb) {List<Predicate> list = new ArrayList<>();if(null != subDepartmentId && !"".equals("subDepartmentId")){list.add(cb.equal(root.<String>get("subDepartmentId"), subDepartmentId));}if(null != status && !"".equals("status")){list.add(cb.equal(root.<String>get("status"), status));}if (null != startTime && !"".equals("startTime")) {list.add(cb.greaterThanOrEqualTo(root.<Date>get("startTime"), DateUtil.stringToDate(startTime)));}if (null != endTime && !"".equals("endTime")) {list.add(cb.lessThanOrEqualTo(root.<Date>get("endTime"), DateUtil.stringToDate(endTime)));}Expression<String> exp = root.<String>get("departmentId");list.add(exp.in(idList)); // 往in中添加所有id 实现in 查询if (list.size() != 0) {Predicate[] p = new Predicate[list.size()];return cb.and(list.toArray(p));} else {return null;}}}, new PageRequest(pageable.getPageNumber(), pageable.getPageSize(), pageable.getSort()));

重点代码：

 

 

  Expression<String> exp = root.<String>get("departmentId");list.add(exp.in(idList)); // idList是部门id集合， 实现in 查询