Spring data mon go Ошибка агрегации [Не удалось создать экземпляр java .util.List с помощью конструктора NO_CONSTRUCTOR с аргументами] - PullRequest
Новая
       62

Spring data mon go Ошибка агрегации [Не удалось создать экземпляр java .util.List с помощью конструктора NO_CONSTRUCTOR с аргументами]

0 голосов
/ 19 февраля 2020

У меня есть следующая структура документа для student_details и subject_details в mongodb. 

student_details
================
{
    "_id" : "STD-1",
    "name" : "XYZ",
    "subjects" : [ 
        {
            "$ref" : "subject_details",
            "$id" : "SUB-1"
        },
        {
            "$ref" : "subject_details",
            "$id" : "SUB-2"
        },
        {
            "$ref" : "subject_details",
            "$id" : "SUB-3"
        }
    ]
}

subject_details
===============
{
    "_id" : "SUB-1",
    "name" : "MATHEMATICS",
    "status" : "ACTIVE"
}

{
    "_id" : "SUB-2",
    "name" : "PHYSICS",
    "status" : "ACTIVE"
}

{
    "_id" : "SUB-3",
    "name" : "CHEMISTRY",
    "status" : "INACTIVE"
}

Теперь, когда я запускаю приведенный ниже запрос с консоли mon go, он выдает мне правильный вывод.

Mon go query 

db.student_details.aggregate([
    {
        $unwind: '$subjects'
    },
    {
        $set: {
            'fk': {
                $arrayElemAt: [{
                    $objectToArray: '$subjects'
                }, 1]
            }
        }
    },
    {
        $lookup: {
            'from': 'subject_details',
            'localField': 'fk.v',
            'foreignField': '_id',
            'as': 'subject'
        }
    },
    {
        $match: {
            'subject.status': 'ACTIVE'
        }
    },
    {
        $group: {
            '_id': '$_id',
            'name': {
                $first: '$name'
            },
            'subjects': {
                $push: {
                    $arrayElemAt: ['$subject', 0]
                }
            }
        }
    }
])

Вывод запроса 

{
    "_id" : "STD-1",
    "name" : "XYZ",
    "subjects" : [ 
        {
            "_id" : "SUB-1",
            "name" : "MATHEMATICS",
            "status" : "ACTIVE"
        }, 
        {
            "_id" : "SUB-2",
            "name" : "PHYSICS",
            "status" : "ACTIVE"
        }
    ]
}

Но когда я пытаюсь преобразовать его в Spring data mon go aggeragation framework, он выдает ошибку Failed to instantiate java.util.List using constructor NO_CONSTRUCTOR with arguments ] with root cause org.springframework.beans.BeanInstantiationException: Failed to instantiate [java.util.List]: Specified class is an interface

Репозиторий данных Spring 

@Repository
public interface StudentDetailRepo extends MongoRepository<StudentDetail, String> {

    @Aggregation(pipeline = {
            "   {" + 
            "        $match: {" + 
            "            'name': 'XYZ'" + 
            "        }" + 
            "    }," + 
            "    {" + 
            "        $unwind: '$subjects'" + 
            "    }," + 
            "    {" + 
            "        $set: {" + 
            "            'fk': {" + 
            "                $arrayElemAt: [{" + 
            "                    $objectToArray: '$subjects'" + 
            "                }, 1]" + 
            "            }" + 
            "        }" + 
            "    }," + 
            "    {" + 
            "        $lookup: {" + 
            "            'from': 'subject_details'," + 
            "            'localField': 'fk.v'," + 
            "            'foreignField': '_id'," + 
            "            'as': 'subject'" + 
            "        }" + 
            "    }," + 
            "    {" + 
            "        $match: {" + 
            "            'subject.status': 'ACTIVE'" + 
            "        }" + 
            "    }," + 
            "    {" + 
            "        $group: {" + 
            "            '_id': '$_id'," + 
            "            'name': {" + 
            "                $first: '$name'" + 
            "            }," + 
            "            'subjects': {" + 
            "                $push: {" + 
            "                    $arrayElemAt: ['$subject', 0]" + 
            "                }" + 
            "            }" + 
            "        }" + 
            "    }"})
    public List<StudentDetail> findStudentWithActiveSubjects();

}
...