MongoUpdateNested.java

package com.conveyal.datatools.manager.persistence;

import com.mongodb.MongoClient;
import com.mongodb.MongoClientOptions;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;
import org.bson.codecs.configuration.CodecRegistry;
import org.bson.codecs.pojo.PojoCodecProvider;
import org.bson.types.ObjectId;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import static com.mongodb.client.model.Filters.eq;
import static com.mongodb.client.model.Updates.set;
import static org.bson.codecs.configuration.CodecRegistries.fromProviders;
import static org.bson.codecs.configuration.CodecRegistries.fromRegistries;

/**
 * Demonstrate updating a single field of a document in Mongo. 
 * This can be done with JSON or with Java objects.
 */
public class MongoUpdateNested {

    public static final Logger LOG = LoggerFactory.getLogger(MongoUpdateNested.class);

    public ObjectId id = new ObjectId();

    public Nest1 inside;

    public static void main (String[] args) {

        PojoCodecProvider pojoCodecProvider = PojoCodecProvider.builder().automatic(true).build();

        CodecRegistry pojoCodecRegistry = fromRegistries(MongoClient.getDefaultCodecRegistry(),
                fromProviders(pojoCodecProvider));

        MongoClient mongoClient = new MongoClient("localhost",
                MongoClientOptions.builder().codecRegistry(pojoCodecRegistry).build());

        MongoDatabase mongoDatabase = mongoClient.getDatabase("nest_test");

        MongoCollection<MongoUpdateNested> collection = mongoDatabase.getCollection(MongoUpdateNested.class.getSimpleName(), MongoUpdateNested.class);

        MongoUpdateNested nest0 = new MongoUpdateNested();

        collection.insertOne(nest0);

        // Update the top level object, giving it a nested object from a JSON document (which could be parsed from text)

        Document subDocument = new Document("content", 12345)
                .append("more", "a")
                .append("blah", "b");

        collection.updateOne(eq(nest0.id), set("inside", subDocument));
        MongoUpdateNested nest0Deserialized = collection.find(eq(nest0.id)).first();
        LOG.info("content: {}", nest0Deserialized.inside.content);

        // Now update the nested field using a Java object rather than a JSON document.

        Nest1 nest1 = new Nest1();
        nest1.content = 9999;
        collection.updateOne(eq(nest0.id), set("inside", nest1));
        nest0Deserialized = collection.find(eq(nest0.id)).first();
        LOG.info("content: {}", nest0Deserialized.inside.content);

    }
    
    public static class Nest1 {
        public int content = 0;
    }

}