我是 mongoDB 的新手。我想在 json 中获取所有时间值,例如:
{ "_id" : { "$oid" : "4ceb753a70fdf877ef5113ca"}, "LoginRequest" : { "Time" : "11-06-2012 11:59:33", "innerAttr4" : "innerValue4"} }
{ "_id" : { "$oid" : "4ceb753a70fdf877ef5113cb"}, "LoginRequest" : { "Time" : "11-06-2012 12:34:05", "innerAttr4" : "innerValue4"} }
搜索后我发现使用点符号。但是点符号在java中对我不起作用。有人可以告诉我该怎么做吗?
我以这种方式使用点符号。但它返回null。
String selectedCollection = "user01"; //WILL CONTAIN THE SELECTED USERNAME
DBCollection coll = db.getCollection(selectedCollection);
ArrayList<String> result = new ArrayList<String>();
//DBObject obj = coll.findOne("LoginRequest.Time");
BasicDBObject query = new BasicDBObject();
BasicDBObject field = new BasicDBObject();
field.put("LoginRequest.Time", 1);
DBCursor cursor = coll.find(query,field);
while (cursor.hasNext()) {
BasicDBObject obj = (BasicDBObject) cursor.next();
result.add(obj.getString("LoginRequest.Time"));
System.out.println(obj.getString("LoginRequest.Time") );
}
如果我在任何地方都用 LoginRequest 替换 LoginRequest.Time,它工作正常。感谢帮助。