源代码：service实现类：
String select_sql = "select cguid,(case isrz when 1 then ‘PASS‘ when 0 then ‘FAIL‘ end) as smrzzt from t_jb_user where mobile=?";
List<Map<String,Object>> list = ydbsDaoI.findList(select_sql, new Object[]{phoneno});//将查询得到的结果取出
String cguid = list.get(0).get("cguid")==null?"":list.get(0).get("cguid").toString();
String smrzzt = list.get(0).get("smrzzt")==null?"":list.get(0).get("smrzzt").toString();
因为没有对取出的结果加判断是否为空，直接取出，所以报错 index：0，size：0
加上if判断后便能正常运行：
String select_sql = "select cguid,(case isrz when 1 then ‘PASS‘ when 0 then ‘FAIL‘ end) as smrzzt from t_jb_user where mobile=?"; List<Map<String,Object>> list = ydbsDaoI.findList(select_sql, new Object[]{phoneno});
if(list != null && list.size() > 0){
//将查询得到的结果取出 String cguid = list.get(0).get("cguid")==null?"":list.get(0).get("cguid").toString(); String smrzzt = list.get(0).get("smrzzt")==null?"":list.get(0).get("smrzzt").toString();
} else {
return;
}
原文：https://www.cnblogs.com/gonghuixin/p/10689009.html