Mongo / Java findAndReplace不工作

email{
"isConfirmed" : true/[or false]
"email" : "xxxxxxxxxxx"
}

isConfirmed

List<String> clientEmails = new ArrayList<String>();

Mongo mongoConnection = new Mongo();

DB mongoDatabase = mongoConnection.getDB(DB_NAME);

DBCollection mongoCollection = mongoDatabase.getCollection(COLLECTION_NAME);

int size = clientEmails.size();

for(int i=0;
i
<
size; i++)

{

    BasicDBObject query = new BasicDBObject();

    System.out.println(clientEmails.get(i).toString());

    query.put("email.email", clientEmails.get(i).toString());

    BasicDBObject Update = new BasicDBObject("$set", new   BasicDBObject("email.isConfirmed", false));

    mongoCollection.update(query, Update); 

  //mongoCollection.findAndModify(query, Update);

//             DBCursor cursor = mongoCollection.find(query);
//

//             while(cursor.hasNext()){

//                 BasicDBObject Update = new BasicDBObject("$set", new BasicDBObject("email.isConfirmed", true));

//                 mongoCollection.update(cursor.next(), Update);
//             }