mongodb QuickStart Demo

本文主要是介绍mongodb QuickStart Demo，对大家解决编程问题具有一定的参考价值，需要的程序猿们随着小编来一起学习吧！

import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoClients;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;
import com.mongodb.client.result.DeleteResult;
import com.mongodb.client.result.UpdateResult;
import org.bson.Document;

import java.util.ArrayList;
import java.util.List;
import java.util.function.Consumer;

import static com.mongodb.client.model.Accumulators.sum;
import static com.mongodb.client.model.Aggregates.group;
import static com.mongodb.client.model.Aggregates.match;
import static com.mongodb.client.model.Aggregates.project;
import static com.mongodb.client.model.Filters.and;
import static com.mongodb.client.model.Filters.eq;
import static com.mongodb.client.model.Filters.exists;
import static com.mongodb.client.model.Filters.gt;
import static com.mongodb.client.model.Filters.gte;
import static com.mongodb.client.model.Filters.lt;
import static com.mongodb.client.model.Filters.lte;
import static com.mongodb.client.model.Projections.excludeId;
import static com.mongodb.client.model.Sorts.descending;
import static com.mongodb.client.model.Updates.inc;
import static com.mongodb.client.model.Updates.set;
import static java.util.Arrays.asList;
import static java.util.Collections.singletonList;
public class QuickTour {
    /**
     * Run this main method to see the output of this quick example.
     *
     * @param args takes an optional single argument for the connection string
     */
    public static void main(final String[] args) throws Exception{
        MongoClient mongoClient;

        if (args.length == 0) {
            // connect to the local database server
            mongoClient = MongoClients.create();
        } else {
            mongoClient = MongoClients.create(args[0]);
        }

        // get handle to "mydb" database
        MongoDatabase database = mongoClient.getDatabase("mydb");


        // get a handle to the "test" collection
        MongoCollection<Document> collection = database.getCollection("test");

        // drop all the data in it
        collection.drop();

        // make a document and insert it
        Document doc = new Document("name", "MongoDB")
                .append("type", "database")
                .append("count", 1)
                .append("info", new Document("x", 203).append("y", 102));

        collection.insertOne(doc);

        // get it (since it's the only one in there since we dropped the rest earlier on)
        Document myDoc = collection.find().first();
        System.out.println(myDoc.toJson());

        // now, lets add lots of little documents to the collection so we can explore queries and cursors
        List<Document> documents = new ArrayList<Document>();
        for (int i = 0; i < 100; i++) {
            documents.add(new Document("i", i));
        }
        collection.insertMany(documents);
        System.out.println("total # of documents after inserting 100 small ones (should be 101) " + collection.countDocuments());

        // find first
        myDoc = collection.find().first();
        System.out.println(myDoc.toJson());

        // lets get all the documents in the collection and print them out
        MongoCursor<Document> cursor = collection.find().iterator();
        try {
            while (cursor.hasNext()) {
                System.out.println(cursor.next().toJson());
            }
        } finally {
            cursor.close();
        }

        for (Document cur : collection.find()) {
            System.out.println(cur.toJson());
        }

        // now use a query to get 1 document out
        myDoc = collection.find(eq("i", 71)).first();
        System.out.println(myDoc.toJson());

        // now use a range query to get a larger subset
        cursor = collection.find(gt("i", 50)).iterator();

        try {
            while (cursor.hasNext()) {
                System.out.println(cursor.next().toJson());
            }
        } finally {
            cursor.close();
        }

        // range query with multiple constraints
        cursor = collection.find(and(gt("i", 50), lte("i", 100))).iterator();

        try {
            while (cursor.hasNext()) {
                System.out.println(cursor.next().toJson());
            }
        } finally {
            cursor.close();
        }

        // Query Filters
        myDoc = collection.find(eq("i", 71)).first();
        System.out.println(myDoc.toJson());

        // now use a range query to get a larger subset
        Consumer<Document> printBlock = new Consumer<Document>() {
            @Override
            public void accept(final Document document) {
                System.out.println(document.toJson());
            }
        };
        collection.find(gt("i", 50)).forEach(printBlock);

        // filter where; 50 < i <= 100
        collection.find(and(gt("i", 50), lte("i", 100))).forEach(printBlock);

        // Sorting
        myDoc = collection.find(exists("i")).sort(descending("i")).first();
        System.out.println(myDoc.toJson());

        // Projection
        myDoc = collection.find().projection(excludeId()).first();
        System.out.println(myDoc.toJson());

        // Aggregation
        collection.aggregate(asList(
                match(gt("i", 0)),
                project(Document.parse("{ITimes10: {$multiply: ['$i', 10]}}")))
        ).forEach(printBlock);

        myDoc = collection.aggregate(singletonList(group(null, sum("total", "$i")))).first();
        System.out.println(myDoc.toJson());

        // Update One
        collection.updateOne(eq("i", 10), set("i", 110));

        // Update Many
        UpdateResult updateResult = collection.updateMany(lt("i", 100), inc("i", 100));
        System.out.println(updateResult.getModifiedCount());

        // Delete One
        collection.deleteOne(eq("i", 110));

        // Delete Many
        DeleteResult deleteResult = collection.deleteMany(gte("i", 100));
        System.out.println(deleteResult.getDeletedCount());

        // Create Index
        collection.createIndex(new Document("i", 1));

        // Clean up
        database.drop();

        // release resources
        mongoClient.close();
    }
}

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