場(chǎng)景

mysql數(shù)據(jù)庫(kù)中

字段為`authority_id` bigint(20) NOT NULL AUTO_INCREMENT COMMENT '權(quán)限ID',

問(wèn)題

public interface BmRoleAuthorityRepository extends JpaRepository{
 
@Query(value = "SELECT authority_id FROM bm_role_authority where role_id = ?1", nativeQuery = true)
List getAllAuthorityIdByRoleId(Long roleId);

直接執(zhí)行，獲取到的List是

之后我想循環(huán)authorityIdList

for (Long authorityId : authorityIdList) {

結(jié)果報(bào)錯(cuò)：

java.lang.ClassCastException: java.math.BigInteger cannot be cast to java.lang.Long

解決方案

沒(méi)有看到有什么特別好的方法，只能將BigInterger的List先轉(zhuǎn)換為String，然后再轉(zhuǎn)換為L(zhǎng)ong List

 
List authorityIdList = bmRoleAuthorityRepository.getAllAuthorityIdByRoleId(roleId);
 
if(authorityIdList == null || authorityIdList.isEmpty()) {
   authorityIdList = new ArrayList<>();
}
String idArray = JSONArray.toJSONString(authorityIdList);

之后再處理這個(gè)String，將其轉(zhuǎn)換為L(zhǎng)ong list

 
// [1,2,3] convert to String[]
String[] split = StringUtils.split(StringUtils.substring(allAuthorityIdByRoleId, 1,
        allAuthorityIdByRoleId.length() - 1), ",");
// guava 將String[] convert to Long[]
authorityIdList.addAll(Lists.transform(Arrays.asList(split), Longs.stringConverter()));