java - 如何使用java代码根据building_Id和floor_Id从MongoDB获取数据？

Question

如何使用java代码根据building_Id和floor_Id从MongoDB获取数据？

例如:如果我发送building_Id = 3 & Floor_Id = 23。我只需要基于building_Id = 3 & Floor_Id = 23 的特定数据列表。

这是 MongoDB 中的示例数据

{
    "_id" : ObjectId("5a685c9bf35e8155da228460"),
    "building_Id" : "3",
    "floor_Id" : "23",
    "x" : "363.0876770019531",
    "y" : "430.05975341796875"
}
{
    "_id" : ObjectId("5a685c9cf35e8155da228462"),
    "building_Id" : "3",
    "floor_Id" : "23",
    "x" : "367.85260009765625",
    "y" : "429.10675048828125"
}
{
    "_id" : ObjectId("5a685c9cf35e8155da228464"),
    "building_Id" : "2",
    "floor_Id" : "22",
    "x" : "375.47650146484375",
    "y" : "429.10675048828125"
}
{
    "_id" : ObjectId("5a685c9cf35e8155da228466"),
    "building_Id" : "2",
    "floor_Id" : "22",
    "x" : "387.8653259277344",
    "y" : "429.10675048828125"
}

这是我从 MongoDb 获取数据的 Java 代码，但我正在从 MongoDb 获取所有数据

    try {           
        MongoClient mongoClient = new MongoClient("localhost", 27017);
        DB db = mongoClient.getDB("trackbitDB");

        DBCollection col = db.getCollection("objects_path");

        BasicDBObject doc = new BasicDBObject();

        // Selecting Records from MongoDB
        col.insert(doc);
        System.out.println("Collection has selected successfully");
        DBCursor cursor = col.find();
        int index = 1;

        while (cursor.hasNext()) {
            System.out.println("Inserted Document: " + index);
            System.out.println(cursor.next());
            index++;
        }           
    } catch(Exception e) {
        e.printStackTrace();
    }

Answer 1

//Build the query
BasicDBObject query = new BasicDBObject("building_Id", "3").append("floor_Id", "23");

//Provide the query as an argumnt to the find()
DBCursor cursor = col.find(query);

//Iterate the cursor
while (cursor.hasNext()) {
    System.out.println(cursor.next());
}