package com.xctdemo.main;

import java.util.ArrayList;
import java.util.List;

import org.bson.Document;

import com.mongodb.MongoClient;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;
import com.mongodb.client.model.Filters;

public class HelloMongoDB {

    public static void main(String[] args) {
        System.out.println("---- Hello MongoDB ----");
        try {
            // 连接到 mongodb 服务
            MongoClient mongoClient = new MongoClient("localhost", 27017);

            // 连接到数据库
            MongoDatabase mongoDatabase = mongoClient.getDatabase("world");
            System.out.println("Connect to database successfully");

            /*
             * mongoDatabase.createCollection("city");
             * System.out.println("集合city创建成功"); //
             */

            // 获取集合
            MongoCollection<Document> collection = mongoDatabase
                    .getCollection("city");
            System.out.println("集合 city 选择成功");

            // 在集合中插入文档
            /**
             * 1. 创建文档 org.bson.Document 参数为key-value的格式 2. 创建文档集合List<Document>
             * 3. 将文档集合插入数据库集合中 mongoCollection.insertMany(List<Document>)
             * 插入单个文档可以用 mongoCollection.insertOne(Document)
             * */
            Document document = new Document("name", "beijing")
                    .append("country", "china").append("provice", "BEIJING")
                    .append("people-count", 1000);
            List<Document> documents = new ArrayList<Document>();
            documents.add(document);
            collection.insertMany(documents);
            System.out.println("文档插入成功-Many");

            Document mydocument = new Document("name", "washington")
                    .append("country", "america")
                    .append("provice", "WASHINGTON")
                    .append("people-count", 1200);
            collection.insertOne(mydocument);

            System.out.println("文档插入成功-One");

            // 检索所有文档
            showDocuments(collection);

            // 删除符合条件的第一个文档
            // collection.deleteOne(Filters.eq("name", "beijing"));
            // 删除所有符合条件的文档
            collection.deleteMany(Filters.eq("name", "beijing"));
            System.out.println("----     deleted OK   ----");
            System.out.println("--------------------------");

            // 更新文档 将文档中likes=100的文档修改为likes=200
            collection.updateMany(Filters.eq("name", "washington"), 
                    new Document("$set", new Document("country", "JAPAN")));
            // 检索所有文档
            showDocuments(collection);

        } catch (Exception e) {
            System.err.println(e.getClass().getName() + ": " + e.getMessage());
        }

        System.out.println("---- over ----");
    }

    private static void showDocuments(MongoCollection<Document> collection) {
        /**
         * 1. 获取迭代器FindIterable<Document> 2. 获取游标MongoCursor<Document> 3.
         * 通过游标遍历检索出的文档集合
         * */
        FindIterable<Document> findIterable = collection.find();
        MongoCursor<Document> mongoCursor = findIterable.iterator();
        while (mongoCursor.hasNext()) {
            System.out.println(mongoCursor.next()); // .get("name")
        }
    }

}