java - Mongodb:如何使用 mongodb java 驱动程序更改嵌套文档的值

Question

我的文档看起来像这样:

{
"_id" : ObjectId("5a5081321d5e182e14f20589"),
"building_number" : "01",
"floor_1" : {
    "roomA" : {
        "occupant" : "vacant",
        "department" : "science",
        "space_code" : "103",
        "space_type" : "office",
        "furniture_assets" : {
            "number_1" : {
                "barcode" : "8076809513456",
                "description" : "Metal Desk",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_2" : {
                "barcode" : "9780444505156",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_3" : {
                "barcode" : "5209533250890",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_4" : {
                "barcode" : "9303939104545",
                "description" : "Gas-lift Chair",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            }
        }
    },
    "roomB" : {
        "occupant" : "vacant",
        "department" : "science",
        "space_code" : "103",
        "space_type" : "office",
        "furniture_assets" : {
            "number_1" : {
                "barcode" : "7258029188960",
                "description" : "Metal Desk",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_2" : {
                "barcode" : "4219366494100",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_3" : {
                "barcode" : "985355502553",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_4" : {
                "barcode" : "930393910527",
                "description" : "Gas-lift Chair",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_4" : {
                "barcode" : "93039391033",
                "description" : "Gas-lift Chair",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            }
        }
    },
    "roomC" : {
        "occupant" : "vacant",
        "department" : "science",
        "space_code" : "103",
        "space_type" : "office",
        "furniture_assets" : {
            "number_1" : {
                "barcode" : "7258021234960",
                "description" : "Metal Desk",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_2" : {
                "barcode" : "4219366741236",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_3" : {
                "barcode" : "985355509513",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_4" : {
                "barcode" : "987593910527",
                "description" : "Gas-lift Chair",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            }
        }
    }
},
"floor_2" : {
    "roomA" : {
        "occupant" : "vacant",
        "department" : "mathematics",
        "space_code" : "105",
        "space_type" : "office",
        "furniture_assets" : {
            "number_1" : {
                "barcode" : "7776809513456",
                "description" : "Metal Desk",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_2" : {
                "barcode" : "9120444505156",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_3" : {
                "barcode" : "4209533250890",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_4" : {
                "barcode" : "9303939104545",
                "description" : "Gas-lift Chair",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            }
        }
    },
    "roomB" : {
        "occupant" : "vacant",
        "department" : "mathematics",
        "space_code" : "105",
        "space_type" : "office",
        "furniture_assets" : {
            "number_1" : {
                "barcode" : "3658029188960",
                "description" : "Metal Desk",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_2" : {
                "barcode" : "2119366494100",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_3" : {
                "barcode" : "495355502553",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_4" : {
                "barcode" : "930393910527",
                "description" : "Gas-lift Chair",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_4" : {
                "barcode" : "46039391033",
                "description" : "Gas-lift Chair",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            }
        }
    },
    "roomC" : {
        "occupant" : "vacant",
        "department" : "mathematics",
        "space_code" : "105",
        "space_type" : "office",
        "furniture_assets" : {
            "number_1" : {
                "barcode" : "7258074124960",
                "description" : "Metal Desk",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_2" : {
                "barcode" : "4219367896236",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_3" : {
                "barcode" : "22535512313",
                "description" : "Pine bookcase",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            },
            "number_4" : {
                "barcode" : "142593910527",
                "description" : "Gas-lift Chair",
                "acquisition_date" : "07/07/2008",
                "cost" : "$100"
            }
        }
    }
  }


}

如何使用 java 驱动程序更改空的对象？

我使用了下面的代码，但它似乎不起作用。

  DBCollection coll = db.getCollection("Facilities");
        String buildingNum = (String) buildingBox.getValue();
        String floorNum = (String) floorBox.getValue();
        String roomNum = (String) roomBox.getValue();
        BasicDBObject document = new BasicDBObject();
        document.put("building_number", buildingNum);
        DBCursor dbCursor = coll.find(document);
        while(dbCursor.hasNext()) {
           DBObject dbo =  dbCursor.next();
        //DBObject  dbObject1 = (DBObject) (((DBObject)  dbo.get(floorNum)).get(roomNum));
         //  String change =  floorNum;
        String email = userDetails.get(0);
         BasicDBObject occupant = new BasicDBObject();

            occupant.append("$set",new BasicDBObject().append( "occupant",email));
         DBObject findRoom = (DBObject) ((DBObject) dbo.get(floorNum)).get(roomNum);

         coll.update(findRoom,occupant,false,false);

即使没有错误，它也不会更改数据库中的值。那么如何使用 java 驱动程序更新“占用者”值呢？有没有办法改变这个值？喜欢此代码的改编吗？

Answer 1

由于您获取了楼层和房间号，因此您可以将文档与建筑物号相匹配，并将更新 key 与楼层和房间号连接起来以更新占用者字段

    String buildingNum = "01";
    String floorNum = "1";
    String roomNum = "A";

    Bson filter = Filters.eq("building_number", buildingNum);
    String key = "floor_" + floorNum + ".room" + roomNum + ".occupant";
    Document update = new Document("$set", new Document(key, "occupied"));
    UpdateOptions options = new UpdateOptions().upsert(false);
    UpdateResult updateResult = coll.updateOne(filter, update, options); // change to many if required

    System.out.println(updateResult.getMatchedCount() + " " + updateResult.getModifiedCount() + " " + updateResult.getUpsertedId());

系统输出

1 1 null

蒙戈集合

> db.Facilities.find({"building_number":"01"},{"floor_2.roomA.occupant" : 1})
{ "_id" : ObjectId("5a51b6c6baf48d5ef9db9f38"), "floor_2" : { "roomA" : { "occupant" : "vacant" } } }
> db.Facilities.find({"building_number":"01"},{"floor_1.roomA.occupant" : 1})
{ "_id" : ObjectId("5a51b6c6baf48d5ef9db9f38"), "floor_1" : { "roomA" : { "occupant" : "occupied" } } } // updated with occupied
> 

编辑

与BasicDBObject

    DBCollection coll = db.getCollection("Facilities");
    String buildingNum = (String) buildingBox.getValue();
    String floorNum = (String) floorBox.getValue();
    String roomNum = (String) roomBox.getValue();
    String key = "floor_" + floorNum + ".room" + roomNum + ".occupant";
    BasicDBObject docFilter = new BasicDBObject("building_number", buildingNum);
    BasicDBObject docUpdate = new BasicDBObject("$set",
            new BasicDBObject(key, "occupied"));
    WriteResult updateResult = coll.update(docFilter, docUpdate);