Java連線Mongo 限制欄位返回數

資料庫中的資料 :

程式碼:

package com.java.module.mongo.mongo_test_1;

import com.mongodb.BasicDBObject;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.MongoClient;

import java.net.UnknownHostException;

/**
 * Java限制欄位返回數
 */
public class JavaFindFields {

    public static void main(String[] args) {
        try {

            MongoClient mongoClient = new MongoClient("localhost", 27017);
            DB db = mongoClient.getDB("test");
            DBCollection dbCollection = db.getCollection("user");


            String[] strArr = new String[]{"name"};
            excludeFields(dbCollection, strArr);

        } catch (UnknownHostException e) {
            e.printStackTrace();
        }
    }


    public static void excludeFields(DBCollection dbCollection, String[] fields) {

        BasicDBObject query = new BasicDBObject("age", new BasicDBObject("$lt", 100));
        BasicDBObject fieldDoc = new BasicDBObject();

        for (int i = 0; i < fields.length; i++) {
            String field = fields[i];
            fieldDoc.append(field, false);
        }


        DBCursor dbCursor = dbCollection.find(query,fieldDoc);
        while (dbCursor.hasNext()) {
            System.out.println(dbCursor.next());
        }


    }

}