How to delete document by _id in MongoDB 3.3 using Java

Question

I'm having a bit of an issue figuring out how to delete a document by _id in MongoDB. I can delete by other attributes no problem but I seem to be missing the correct syntax for deleting by _id.

My document has the following format :

{ "_id" : { "$oid" : "57a49c6c33b10927ff09623e" }, "name" : "Brad" }

And here is the Java code I am using :

// Boiler plate
MongoClient client = new MongoClient( "localhost" , 27017 );
MongoDatabase db = client.getDatabase("my-database");
MongoCollection<Document> collection = db.getCollection("my-collection")

// This works
collection.deleteOne(new Document("name", "Brad"));

// This does not work
collection.deleteOne(new Document("_id", "57a49c6c33b10927ff09623e"));

Anyone have any idea where I am going wrong?

Answer 1

Field _id has type ObjectId, and "57a49c6c33b10927ff09623e" has type String.

Instead try

collection.deleteOne(new Document("_id", new ObjectId("57a49c6c33b10927ff09623e")));