Jpa 使用Specification构建复杂查询

JPA and中添加or查询条件
eg: 查询当前用户支付状态为1，任务运行状态为1或0的所有任务信息。
sql: select * from task where user_id=1 and billing_status=1 and status=1 or 0

怎样将查询条件封装到jpa的查询对象中呢？

public List<EmailGradeTask> findTaskByUserIdAndStatusAndBillingStatus(Integer userId){

	List<EmailGradeTask> gradeTaskList = emailGradeTaskRepository.findAll(new Specification<EmailGradeTask>() {
		@Nullable
		@Override
		public Predicate toPredicate(Root<EmailGradeTask> root, CriteriaQuery<?> criteriaQuery, CriteriaBuilder 
		criteriaBuilder) {
			//封装and查询条件
			List<Predicate> list = new ArrayList<>();
			list.add(criteriaBuilder.equal(root.get("userId"), userId));
			list.add(criteriaBuilder.equal(root.get("billingStatus"), "1"));
			Predicate[] predicates = new Predicate[list.size()];
			Predicate predicateWhere = criteriaBuilder.and(list.toArray(predicates));
			//封装or查询条件
			List<Predicate> listPermission = new ArrayList<>();
			listPermission.add(criteriaBuilder.equal(root.get("status"), 1));
			listPermission.add(criteriaBuilder.equal(root.get("status"), 0));
			Predicate[] predicatesPermissionArr = new Predicate[listPermission.size()];
			Predicate predicatesPermission = criteriaBuilder.or(listPermission.toArray(predicatesPermissionArr));
			//两条件合并
			Predicate restriction = criteriaQuery.where(predicateWhere, predicatesPermission).getRestriction();
			return restriction;
		}
	});
	return  gradeTaskList;
}
}