Mongo java driver add fields value population from indexOfArray-CodePudding

db.collection.aggregate([
{
$match : { filterQuery}
},
{
$addFields :{ “customGradeOrder” : { $indexOfArray: [ [“Gold”, “Silver”, “Bronze”] , “$grade” ] }}
},{$sort : { customGradeOrder : 1 } }
]);

Does mongo java driver Aggregates has any method to add fields with values resolved from index of array operator ?

Example ::

Student 1: Name grade A Silver

Student 2 : Name grade B Gold

Student 3: Name grade : C Bronze

The query is to query the student collection and get it sorted in specific value of grades of students (not in simple ascending or descending order.)

Output would be : B Gold A Silver C Bronze

CodePudding user response：

This works as well, apart from the solution you mentioned:

FindIterable<Document> result = collection.aggregate(Arrays.asList(new Document("$addFields", 
    new Document("customGradeOrder", 
    new Document("$indexOfArray", Arrays.asList(Arrays.asList("Gold", "Silver", "Bronze"), "$grade")))), 
    new Document("$sort", 
    new Document("customGradeOrder", 1L))));