MongoDB学习(三) --- MongoDB Java入门

1、搭建测试环境

• 步骤一：创建 Maven 项目

• 父项目的pom文件

  
  
      4.0.0
  
      com.tqylxuecheng
      xc_parent
      pom
      1.0-SNAPSHOT
      
          xc_test_parent
      
  
  
      
      
          org.springframework.boot
          spring-boot-starter-parent
          2.1.4.RELEASE
      
      
      
          UTF-8
          1.8
          Greenwich.RELEASE
          1.3.2
          2.0.3
          1.2.3
          1.1.9
          5.1.32
          1.16.20
          2.6
          1.3.2
          1.3.3
          1.10
          3.6
          3.9.1
          8.18.0
          2.7.0
          1.2.9
          1.27.0.0
          24.0-jre
      
  
      
      
          
              
              
                  org.springframework.cloud
                  spring-cloud-dependencies
                  ${spring-cloud-release.version}
                  pom
                  import
              
  
              
              
                  org.mybatis.spring.boot
                  mybatis-spring-boot-starter
                  ${mybatis.starter.version}
              
              
              
                  tk.mybatis
                  mapper-spring-boot-starter
                  ${mapper.starter.version}
              
              
                  com.GitHub.pagehelper
                  pagehelper-spring-boot-starter
                  ${pageHelper.starter.version}
              
              
              
                  com.alibaba
                  druid-spring-boot-starter
                  ${druid.starter.version}
              
              
                  Mysql
                  mysql-connector-java
                  ${mysql-connector-java.version}
              
  
              
                  com.squareup.okHttp3
                  okhttp
                  ${okhttp.version}
              
              
                  com.netflix.feign
                  feign-okhttp
                  ${feign-okhttp.version}
              
              
                  commons-io
                  commons-io
                  ${commons-io.version}
              
              
                  org.apache.commons
                  commons-io
                  ${org.apache.commons.io.version}
              
              
                  commons-fileupload
                  commons-fileupload
                  ${commons-fileupload.version}
              
              
                  commons-codec
                  commons-codec
                  ${commons-codec.version}
              
              
                  org.apache.commons
                  commons-lang3
                  ${commons-lang3.version}
              
  
              
              
                  io.springfox
                  springfox-swagger2
                  ${springfox-swagger.version}
              
              
                  io.springfox
                  springfox-swagger-ui
                  ${springfox-swagger.version}
              
  
              
              
                  net.oschina.zcx7878
                  fastdfs-client-java
                  ${fastdfs-client-java.version}
              
  
              
                  com.Google.guava
                  guava
                  ${guava.version}
              
  
          
      
      
      
          
              spring-milestones
              Spring Milestones
              https://repo.spring.io/milestone
              
                  false
              
          
      
  
  
  

• 步骤三：子模块测试

• 结构目录

• test_mongo 的 pom文件添加依赖

   
          
          
              org.springframework.boot
              spring-boot-starter-test
          
          
          
              org.mongoDB
              mongo-java-driver
              3.4.3
          
  
      
  

2、基本操作

• 创建测试类 Test01

2.1、获得连接

• 方式1：连接本地数据库

   @Test
      public void testConnection() {
          //获得本地连接
          MongoClient mongoClient = new MongoClient("localhost", 27017);
          System.out.println(mongoClient);
      }
  

• 方式2：采用连接字符串

  @Test
      public void testConnection2() {
          //获得连接
          //拼凑连接字符串
          MongoClientURI connectionString = new MongoClientURI("mongodb://root:1234@localhost:27017");  
          //获得连接
          MongoClient mongoClient = new MongoClient(connectionString);
          System.out.println(mongoClient);
      }
  

2.2、查询第一个

    @Test
    public void testFindOne(){
        //查询一个
        //1 获得连接
        MongoClientURI mongoClientURI = new MongoClientURI("mongodb://root:1234@localhost:27017");
        MongoClient mongoClient = new MongoClient(mongoClientURI);

        // 2 获得数据库
        MongoDatabase database = mongoClient.getDatabase("demo");

        //3 获得集合
        MongoCollection studentCollection = database.getCollection("student");

        //4 查询操作
        Document document = studentCollection.find().first();

        //5 将文档转换JSON，并输出
        System.out.println(document.tojson());

    }

2.3、创建集合

    @Test
    public void testCreateColl(){
        //1 获得连接
        MongoClientURI mongoClientURI = new MongoClientURI("mongodb://root:1234@localhost:27017");
        MongoClient mongoClient = new MongoClient(mongoClientURI);
        //2 获得数据库
        MongoDatabase database = mongoClient.getDatabase("demo");
        //3 创建集合
        database.createCollection("teacher");
    }

2.4、插入一个文档

    @Test
    public void testInsertDocument(){
        //1 获得连接
        MongoClientURI mongoClientURI = new MongoClientURI("mongodb://root:1234@localhost:27017");
        MongoClient mongoClient = new MongoClient( mongoClientURI );
        //2 获得数据库
        MongoDatabase database = mongoClient.getDatabase("demo");

        //3 获得集合
        MongoCollection collection = database.getCollection("teacher");

        //4 准备文档
        Document document = new Document();
        document.append("username","jack");
        document.append("passWord","1234");
        document.append("age", 18 );

        //5 录入文档
        collection.insertOne(document);
    }

2.5、批量插入文档

    @Test
    public void testInsertManyDocument(){
        //批量插入
        //1 获得连接
        MongoClientURI mongoClientURI = new MongoClientURI("mongodb://root:1234@localhost:27017");
        MongoClient mongoClient = new MongoClient(mongoClientURI);
        //2 获得数据库
        MongoDatabase database = mongoClient.getDatabase("demo");
        //3 获得集合
        MongoCollection collection = database.getCollection("teacher");
        //4 准备一组数据
        Document doc = new Document();
        doc.append("username","rose");
        doc.append("password","1234");
        doc.append("age", 21 );

        Document doc2 = new Document();
        doc2.append("username","tom");
        doc2.append("password","666");
        doc2.append("age", 25 );

        List list = new ArrayList<>();
        list.add( doc );
        list.add( doc2 );

        //5 批量插入
        collection.insertMany( list );

    }

2.6、查询所有

 @Test
    public void testFindAll(){

        //1 获得连接
        MongoClientURI mongoClientURI = new MongoClientURI("mongodb://root:1234@localhost:27017");
        MongoClient mongoClient = new MongoClient(mongoClientURI);
        //2 获得数据库
        MongoDatabase database = mongoClient.getDatabase("demo");
        //3 获得集合
        MongoCollection collection = database.getCollection("teacher");
        //4 查询所有
        FindIterable findIterable = collection.find();
        //5 处理数据（遍历迭代器）
        MongoCursor it = findIterable.iterator();
        while( it.hasNext() ){
            Document document = it.next();
            String username = document.get("username", String.class);
            String password = document.get("password", String.class);
            Integer age = document.get("age", Integer.class);

            System.out.println(username + "_" + password + "_" + age);
        }

2.7、更新文档

@Test
public void testUpdate() {
    // 采用连接字符串
    MongoClientURI connectionString = new MongoClientURI("mongodb://root:1234@localhost:27017");
    MongoClient mongoClient = new MongoClient(connectionString);
    // 连接数据库
    MongoDatabase database = mongoClient.getDatabase("demo");
    // 获得集合
    MongoCollection collection = database.getCollection("teacher");

    // 更新
    collection.updateOne(Filters.eq("age",20), new Document("$set", new Document("name","YY老师")));

}

2.8、删除文档

@Test
public void testDelete() {
    // 采用连接字符串
    MongoClientURI connectionString = new MongoClientURI("mongodb://root:1234@localhost:27017");
    MongoClient mongoClient = new MongoClient(connectionString);
    // 连接数据库
    MongoDatabase database = mongoClient.getDatabase("demo");
    // 获得集合
    MongoCollection collection = database.getCollection("teacher");

    // 删除
    collection.deleteOne(Filters.eq("age",20));

}