如何编写用于在Spring中将数组转换为对象的MongoDB聚合查询？

Question

这是我的mongoDB聚合查询，可在mongoDB shell中完美运行：

const storage = this._storage.getStoredData();

我试图在Java中获得相同的东西Springboot。令我震惊的是获得“参与”部分，即获得这一点：

db.objectData.aggregate([{$project:{newFieldList:{$arrayToObject: { "$map" : { "input" : "$fieldList", "as" : "fieldList", "in" : { k: "$$fieldList.fieldVal", v: "$$fieldList.value" } } }}}}]).pretty()

这是我现在拥有的：

{ k: "$$fieldList.fieldVal", v: "$$fieldList.value" }

上面的代码打印：

Map map = VariableOperators.Map.itemsOf("fieldList").as("fieldList").andApply(ArrayOperators.ArrayElemAt.arrayOf("fieldList.fieldVal"));
ArrayToObject arrayToObject = ArrayOperators.ArrayToObject.arrayToObject(map);
ProjectionOperationBuilder projectBuilder = Aggregation.project().and(arrayToObject);
ProjectionOperation projectStage = projectBuilder.as("newFieldList");
Aggregation agg = Aggregation.newAggregation(projectStage);
System.out.println("query = " + agg.toString());

您能帮我找到要在springboot中用'andApply'编写的聚合表达式吗？

query = { "aggregate" : "__collection__", "pipeline" : [{ "$project" : { "newFieldList" : { "$arrayToObject" : { "$map" : { "input" : "$fieldList", "as" : "fieldList", "in" : { "$arrayElemAt" : ["$$fieldList.fieldVal"] } } } } } }] }