mongodb java api

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>org.example</groupId>
    <artifactId>A01mongodb</artifactId>
    <version>1.0-SNAPSHOT</version>

    <dependencies>
        <!-- https://mvnrepository.com/artifact/org.mongodb/mongodb-driver -->
        <dependency>
            <groupId>org.mongodb</groupId>
            <artifactId>mongodb-driver</artifactId>
            <version>3.12.7</version>
        </dependency>
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-compiler-plugin</artifactId>
                <configuration>
                    <source>1.9</source>
                    <target>1.9</target>
                </configuration>
            </plugin>
        </plugins>
    </build>
</project>

package com.wuxi.test;

import com.mongodb.MongoClient;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

public class MyTest {
    private MongoDatabase student = null;
    private MongoClient client = null;

    @Before
    public void before() {
        //链接mongo服务器
        client = new MongoClient("127.0.0.1");
        //得到要操作的数据库
        student = client.getDatabase("student");
    }

    @After
    public void after() {
        client.close();
    }

    @Test
    public void test01() {
        //得到要操作的表
        MongoCollection<Document> persons = student.getCollection("person");
        //操作表

        //查询所有
        FindIterable<Document> documents = persons.find();
        for (Document document : documents) {
            String str = "{_id:" + document.getString("_id") + ",name:" +
                    document.getString("name") + ",age:" + document.getInteger("age") + "}";
            System.out.println(str);
        }

/*
        //简单条件查询
        BasicDBObject bson = new BasicDBObject("name", "mengmeiqi");
        FindIterable<Document> documents = persons.find(bson);
        for (Document document : documents) {
            String str = "{_id:" + document.getString("_id") + ",name:" +
                    document.getString("name") + ",age:" + document.getInteger("age") + "}";
            System.out.println(str);
        }

        //复杂条件查询
        BasicDBObject bson = new BasicDBObject("age", new BasicDBObject("$lt", 20));
        FindIterable<Document> documents = persons.find(bson);
        for (Document document : documents) {
            String str = "{_id:" + document.getString("_id") + ",name:" +
                    document.getString("name") + ",age:" + document.getInteger("age") + "}";
            System.out.println(str);
        }

        //添加数据
        Map<String, Object> map = new HashMap<>();
        map.put("_id", "6");
        map.put("name", "baixiaowu");
        map.put("age", 27);
        Document document = new Document(map);
        persons.insertOne(document);
*/
    }
}