查找集合Java Mongodb中的所有对象 [英] Find all objects in collection Java Mongodb

问题描述

下面的代码在集合中找到第一个文档:

Below code finds the first document in a collection :

package database;

import com.mongodb.BasicDBObject;
import com.mongodb.BulkWriteOperation;
import com.mongodb.BulkWriteResult;
import com.mongodb.Cursor;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;
import com.mongodb.MongoClient;
import com.mongodb.ParallelScanOptions;
import com.mongodb.ServerAddress;

import java.net.UnknownHostException;
import java.util.List;
import java.util.Set;

import static java.util.concurrent.TimeUnit.SECONDS;

// based on http://mongodb.github.io/mongo-java-driver/2.13/getting-started/quick-tour/

public class Mongo {

    public void getCon() {
        // or
        MongoClient mongoClient;
        try {
            mongoClient = new MongoClient("localhost", 27017);
            DB db = mongoClient.getDB("mydb");
            DBCollection coll = db.getCollection("testCollection");

            BasicDBObject doc = new BasicDBObject("name", "MongoDB")
                    .append("type", "database")
                    .append("count", 1)
                    .append("info",
                            new BasicDBObject("x", 203).append("y", 102));
            coll.insert(doc);

            coll.findOne();
        } catch (UnknownHostException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

    }
}

似乎没有findAll方法.如何在集合testCollection中找到所有文档?

There does not appear to be a findAll method. How to find all the documents in the collection testCollection ?

推荐答案

您必须使用

You have to use the DBCollection.find() method, which

选择集合中的所有文档，然后将光标移至所选文档.

Select all documents in collection and get a cursor to the selected documents.

所以，您要做的是:

DBCursor cursor = coll.find();
while (cursor.hasNext()) {
   DBObject obj = cursor.next();
   //do your thing
}

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