java - 改造 - MongoDB - 预期 BEGIN_ARRAY 但为 BEGIN_OBJECT

Question

我正在尝试从 mongodb 接收一些数据。这是格式，我收到：

 {
  "_id": {
    "$oid": "56906e7ee4b0166e3b6a1a4a"
  },
  "plant": [
    {
      "documentId": "8923597",
      "latitude": "51.504169",
      "longitude": "7.462922",
      "stage": "4",
      "seeds": "erdbeere",
      "createAt": "08.01.2016",
      "seedColor": "red"
    },
    {
      "documentId": "5340284",
      "latitude": "51.5147365",
      "longitude": "7.4640148",
      "stage": "1",
      "seeds": "chili",
      "createAt": "24.12.2015",
      "seedColor": "green"
    }
  ]
}

我正在使用改造来获得它。

MongolabDocumentConnector jsonConnection =
 retrofit.create(MongolabDocumentConnector.class);

Call call = 
 jsonConnection.contributors("myDBData", "myCollection", "myDocumentkey", "myApiKey");

我的结构如下所示：

public class PlantDBStructure {
public final float lat;
public final float lon;
public final int stage;
public final String seeds;
public final Date created;
public final Color seedColor;

public PlantDBStructure(float lat, float lon, int stage, String seeds, Date created, Color seedColor) {
    this.lat = lat;
    this.lon=lon;
    this.stage=stage;
    this.seeds=seeds;
    this.created=created;
    this.seedColor=seedColor;
 }
}

当我运行代码时，我得到了异常：

com.google.gson.JsonSyntaxException: java.lang.IllegalStateException: 预期 BEGIN_ARRAY 但在第 1 行第 2 列路径 $...

我知道我必须更改 PlantDBStructure，但我真的不知道怎么做。请帮忙。非常感谢！