MongoDB：在 Java 中使用 MongoDB

本是古典何须时尚 2023-09-23 21:13 39阅读 0赞

> 除了通过启动 mongo 进程进如 Shell 环境访问数据库外，MongoDB 还提供了其他基于编程语言的访问数据库方法。MongoDB 官方提供了 Java 语言的驱动包，利用这些驱动包可使用多种编程方法来连接并操作 MongoDB 数据库。
> 
> 想要在 Java 程序中使用 MongoDB，需要确保您的电脑上已经安装了 MongoDB，并搭建好了 Java 的环境。
> 
> 本篇内容主要介绍：Java 实现对 MongDB 的操作、Java 操作 MongoDB 数据库 Demo

--------------------

### 文章目录 ###

*   *  一、Java 实现对 MongDB 的操作
     *   *   *  1、前提条件
             *  2、添加依赖
     *  二、Java 操作 MongoDB 数据库 Demo
     *   *   *  1、连接数据库
             *  2、创建集合
             *  3、列出所有集合
             *  4、获取/选择集合
             *  5、插入文档
             *  6、查询文档
             *  7、更新文档
             *  8、删除文档
             *  9、删除集合

--------------------

## 一、Java 实现对 MongDB 的操作 ##

#### 1、前提条件 ####

除了通过启动 mongo 进程进如 Shell 环境访问数据库外，MongoDB 还提供了其他基于编程语言的访问数据库方法。MongoDB 官方提供了 Java 语言的驱动包，利用这些驱动包可使用多种编程方法来连接并操作 MongoDB 数据库。

想要在 Java 程序中使用 MongoDB，需要确保您的电脑上已经安装了 MongoDB，并搭建好了 Java 的环境。

#### 2、添加依赖 ####

在 Maven 中添加以下依赖来使用操作 MongoDB 数据库：

<dependencies>
            <dependency>
                <groupId>org.mongodb</groupId>
                <artifactId>bson</artifactId>
                <version>3.12.11</version>
            </dependency>
            <dependency>
                <groupId>org.mongodb</groupId>
                <artifactId>mongodb-driver</artifactId>
                <version>3.12.11</version>
            </dependency>
            <dependency>
                <groupId>org.mongodb</groupId>
                <artifactId>mongodb-driver-core</artifactId>
                <version>3.12.11</version>
            </dependency>
           
            ...
        </dependencies>

--------------------

## 二、Java 操作 MongoDB 数据库 Demo ##

#### 1、连接数据库 ####

package com.lizhengi.demo;
    
    import com.mongodb.client.MongoDatabase;
    import com.mongodb.MongoClient;
    import com.mongodb.MongoCredential;
    
    /**
     * @author liziheng
     * @version 1.0.0
     * @description 连接数据库
     * @date 2023-01-04 5:19 下午
     **/
    public class ConnectToMongodb {
        
    
        public static void main(String[] args) {
        
            // 创建 MongoDB 连接
            MongoClient mongo = new MongoClient("localhost", 27017);
    
            // 连接到 MongoDB
            MongoCredential credential = MongoCredential.createCredential("lizhengi", "lizhengi", "password".toCharArray());
            System.out.println("Credentials ::" + credential);
    
            // 访问数据库
            MongoDatabase database = mongo.getDatabase("lizhengi");
            System.out.println("Connect to database successfully!");
            System.out.println("MongoDatabase info is : " + database.getName());
        }
    }

运行 Main 函数，返回以下结果：

#### 2、创建集合 ####

package com.lizhengi.demo;
    
    import com.mongodb.client.MongoDatabase;
    import com.mongodb.MongoClient;
    import com.mongodb.MongoCredential;
    
    /**
     * @author liziheng
     * @version 1.0.0
     * @description 创建集合
     * @date 2023-01-04 7:36 下午
     **/
    public class CreatingCollection {
        public static void main(String[] args) {
            // 创建 MongoDB 连接
            MongoClient mongo = new MongoClient("localhost", 27017);
    
            // 连接到 MongoDB
            MongoCredential credential = MongoCredential.createCredential("lizhengi", "lizhengi", "password".toCharArray());
            System.out.println("Credentials ::" + credential);
    
            // 访问数据库
            MongoDatabase database = mongo.getDatabase("lizhengi");
            System.out.println("Connect to database successfully!");
            System.out.println("MongoDatabase info is : " + database.getName());
    
            // 创建集合
            database.createCollection("lizhengi_test_3");
            System.out.println("create collection successfully!");
        }
    }

运行 Main 函数，返回以下结果：

#### 3、列出所有集合 ####

package com.lizhengi.demo;
    
    import com.mongodb.MongoClient;
    import com.mongodb.MongoCredential;
    import com.mongodb.client.MongoCollection;
    import com.mongodb.client.MongoDatabase;
    import org.bson.Document;
    
    /**
     * @author liziheng
     * @version 1.0.0
     * @description 列出所有集合
     * @date 2023-01-04 7:56 下午
     **/
    public class ListOfCollection {
        
    
        public static void main(String[] args) {
        
            // 创建 MongoDB 连接
            MongoClient mongo = new MongoClient("localhost", 27017);
    
            // 连接到 MongoDB
            MongoCredential credential = MongoCredential.createCredential("lizhengi", "lizhengi", "password".toCharArray());
            System.out.println("Credentials ::" + credential);
    
            // 访问数据库
            MongoDatabase database = mongo.getDatabase("lizhengi");
            System.out.println("Connect to database successfully!");
            System.out.println("MongoDatabase info is : " + database.getName());
    
            // 检索集合列表
            for (String name : database.listCollectionNames()) {
        
                System.out.println(name);
            }
        }
    }

运行 Main 函数，返回以下结果：

#### 4、获取/选择集合 ####

package com.lizhengi.demo;
    
    import com.mongodb.MongoClient;
    import com.mongodb.MongoCredential;
    import com.mongodb.client.MongoCollection;
    import com.mongodb.client.MongoDatabase;
    import org.bson.Document;
    
    /**
     * @author liziheng
     * @version 1.0.0
     * @description 获取/选择集合
     * @date 2023-01-04 7:40 下午
     **/
    public class SelectingCollection {
        
    
        public static void main(String[] args) {
        
            // 创建 MongoDB 连接
            MongoClient mongo = new MongoClient("localhost", 27017);
    
            // 连接到 MongoDB
            MongoCredential credential = MongoCredential.createCredential("lizhengi", "lizhengi", "password".toCharArray());
            System.out.println("Credentials ::" + credential);
    
            // 访问数据库
            MongoDatabase database = mongo.getDatabase("lizhengi");
            System.out.println("Connect to database successfully!");
            System.out.println("MongoDatabase info is : " + database.getName());
    
            // 创建集合
            MongoCollection<Document> collection = database.getCollection("lizhengi");
            System.out.println("chose collection : " + collection.getNamespace());
        }
    }

运行 Main 函数，返回以下结果：

#### 5、插入文档 ####

package com.lizhengi.demo;
    
    import com.mongodb.MongoClient;
    import com.mongodb.MongoCredential;
    import com.mongodb.client.MongoCollection;
    import com.mongodb.client.MongoDatabase;
    import org.bson.Document;
    
    /**
     * @author liziheng
     * @version 1.0.0
     * @description 插入文档
     * @date 2023-01-04 7:45 下午
     **/
    public class InsertingDocument {
        
    
        public static void main(String[] args) {
        
            // 创建 MongoDB 连接
            MongoClient mongo = new MongoClient("localhost", 27017);
    
            // 连接到 MongoDB
            MongoCredential credential = MongoCredential.createCredential("lizhengi", "lizhengi", "password".toCharArray());
            System.out.println("Credentials ::" + credential);
    
            // 访问数据库
            MongoDatabase database = mongo.getDatabase("lizhengi");
            System.out.println("Connect to database successfully!");
            System.out.println("MongoDatabase info is : " + database.getName());
    
            // 检索集合
            MongoCollection<Document> collection = database.getCollection("lizhengi");
            System.out.println("chose collection : " + collection.getNamespace());
    
            Document document = new Document("title", "MongoDB")
                    .append("description", "database")
                    .append("likes", 200)
                    .append("url", "https://lizhengi.blog.csdn.net/")
                    .append("by", "lizhengi");
    
            // 将文档插入到集合中
            collection.insertOne(document);
            System.out.println("Document insert successfully!");
        }
    }

运行 Main 函数，返回以下结果：

#### 6、查询文档 ####

package com.lizhengi.demo;
    
    import com.mongodb.client.FindIterable;
    import com.mongodb.client.MongoCollection;
    import com.mongodb.client.MongoDatabase;
    import org.bson.Document;
    import com.mongodb.MongoClient;
    import com.mongodb.MongoCredential;
    
    /**
     * @author liziheng
     * @version 1.0.0
     * @description 查询文档
     * @date 2023-01-04 7:52 下午
     **/
    public class RetrievingAllDocuments {
        
    
        public static void main(String[] args) {
        
            // 创建 MongoDB 连接
            MongoClient mongo = new MongoClient("localhost", 27017);
    
            // 连接到 MongoDB
            MongoCredential credential = MongoCredential.createCredential("lizhengi", "lizhengi", "password".toCharArray());
            System.out.println("Credentials ::" + credential);
    
            // 访问数据库
            MongoDatabase database = mongo.getDatabase("lizhengi");
            System.out.println("Connect to database successfully!");
            System.out.println("MongoDatabase info is : " + database.getName());
    
            // 检索集合
            MongoCollection<Document> collection = database.getCollection("lizhengi");
            System.out.println("chose collection : " + collection.getNamespace());
    
            // 获取 iterable 对象
            FindIterable<Document> iterDoc = collection.find();
            int i = 1;
            // 获取迭代器
            for (Document document : iterDoc) {
        
                System.out.println(document);
                i++;
            }
        }
    }

运行 Main 函数，返回以下结果：

> Credentials ::MongoCredential\{mechanism=null, userName=‘lizhengi’, source=‘lizhengi’, password=, mechanismProperties=\}  
> Connect to database successfully!  
> MongoDatabase info is : lizhengi  
> chose collection : lizhengi.lizhengi
> 
> Document\{ \{\_id=63b5676adcb7bc291eb5285d, title=MongoDB, description=database, likes=200, url=https://lizhengi.blog.csdn.net/, by=lizhengi\}\}  
> Document\{ \{\_id=63b568fa76a0f93c0a6c9f2a, title=MongoDB, description=database, likes=200, url=https://lizhengi.blog.csdn.net/, by=lizhengi2\}\}

#### 7、更新文档 ####

package com.lizhengi.demo;
    
    import com.mongodb.MongoClient;
    import com.mongodb.MongoCredential;
    import com.mongodb.client.FindIterable;
    import com.mongodb.client.MongoCollection;
    import com.mongodb.client.MongoDatabase;
    import com.mongodb.client.model.Filters;
    import com.mongodb.client.model.Updates;
    import org.bson.Document;
    
    /**
     * @author liziheng
     * @version 1.0.0
     * @description 更新文档
     * @date 2023-01-04 7:59 下午
     **/
    public class UpdatingDocuments {
        
    
        public static void main(String[] args) {
        
            // 创建 MongoDB 连接
            MongoClient mongo = new MongoClient("localhost", 27017);
    
            // 连接到 MongoDB
            MongoCredential credential = MongoCredential.createCredential("lizhengi", "lizhengi", "password".toCharArray());
            System.out.println("Credentials ::" + credential);
    
            // 访问数据库
            MongoDatabase database = mongo.getDatabase("lizhengi");
            System.out.println("Connect to database successfully!");
            System.out.println("MongoDatabase info is : " + database.getName());
    
            // 检索集合
            MongoCollection<Document> collection = database.getCollection("lizhengi");
            System.out.println("chose collection : " + collection.getNamespace());
    
            // 更新单个可用 updateOne
            collection.updateMany(Filters.eq("title", "MongoDB"), Updates.set("likes", 150));
            System.out.println("Document update successfully...");
            // 更新后检索文档
            // 获取 iterable 对象
            FindIterable<Document> iterDoc = collection.find();
            int i = 1;
            // 获取迭代器
            for (Document document : iterDoc) {
        
                System.out.println(document);
                i++;
            }
        }
    }

运行 Main 函数，返回以下结果：

>     Credentials ::MongoCredential{mechanism=null, userName='lizhengi', source='lizhengi', password=<hidden>, mechanismProperties=<hidden>}
>     Connect to database successfully!
>     MongoDatabase info is : lizhengi
>     chose collection : lizhengi.lizhengi
>     Document update successfully...
>     Document{
>         {_id=63b5676adcb7bc291eb5285d, title=MongoDB, description=database, likes=150, url=https://lizhengi.blog.csdn.net/, by=lizhengi}}
>     Document{
>         {_id=63b568fa76a0f93c0a6c9f2a, title=MongoDB, description=database, likes=200, url=https://lizhengi.blog.csdn.net/, by=lizhengi2}}

#### 8、删除文档 ####

package com.lizhengi.demo;
    
    import com.mongodb.MongoClient;
    import com.mongodb.MongoCredential;
    import com.mongodb.client.FindIterable;
    import com.mongodb.client.MongoCollection;
    import com.mongodb.client.MongoDatabase;
    import com.mongodb.client.model.Filters;
    import org.bson.Document;
    
    /**
     * @author liziheng
     * @version 1.0.0
     * @description 删除文档
     * @date 2023-01-04 8:03 下午
     **/
    public class DeletingDocuments {
        
    
        public static void main(String[] args) {
        
            // 创建 MongoDB 连接
            MongoClient mongo = new MongoClient("localhost", 27017);
    
            // 连接到 MongoDB
            MongoCredential credential = MongoCredential.createCredential("lizhengi", "lizhengi", "password".toCharArray());
            System.out.println("Credentials ::" + credential);
    
            // 访问数据库
            MongoDatabase database = mongo.getDatabase("lizhengi");
            System.out.println("Connect to database successfully!");
            System.out.println("MongoDatabase info is : " + database.getName());
    
            // 检索集合
            MongoCollection<Document> collection = database.getCollection("lizhengi");
            System.out.println("chose collection : " + collection.getNamespace());
    
            // 删除文档 删除多个可用 deleteMany
            collection.deleteOne(Filters.eq("title", "MongoDB"));
            System.out.println("Document delete successfully...");
            // 删除后检索文档
            // 获取 iterable 对象
            FindIterable<Document> iterDoc = collection.find();
            int i = 1;
            // 获取迭代器
            for (Document document : iterDoc) {
        
                System.out.println(document);
                i++;
            }
        }
    }

运行 Main 函数，返回以下结果：

> Credentials ::MongoCredential\{mechanism=null, userName=‘lizhengi’, source=‘lizhengi’, password=, mechanismProperties=\}  
> Connect to database successfully!  
> MongoDatabase info is : lizhengi  
> chose collection : lizhengi.lizhengi
> 
> Document delete successfully…  
> Document\{ \{\_id=63b568fa76a0f93c0a6c9f2a, title=MongoDB, description=database, likes=200, url=https://lizhengi.blog.csdn.net/, by=lizhengi2\}\}

#### 9、删除集合 ####

package com.lizhengi.demo;
    
    import com.mongodb.MongoClient;
    import com.mongodb.MongoCredential;
    import com.mongodb.client.MongoCollection;
    import com.mongodb.client.MongoDatabase;
    import org.bson.Document;
    
    /**
     * @author liziheng
     * @version 1.0.0
     * @description 删除集合
     * @date 2023-01-04 8:06 下午
     **/
    public class DropingCollection {
        
    
        public static void main(String[] args) {
        
            // 创建 MongoDB 连接
            MongoClient mongo = new MongoClient("localhost", 27017);
    
            // 连接到 MongoDB
            MongoCredential credential = MongoCredential.createCredential("lizhengi", "lizhengi", "password".toCharArray());
            System.out.println("Credentials ::" + credential);
    
            // 访问数据库
            MongoDatabase database = mongo.getDatabase("lizhengi");
            System.out.println("Connect to database successfully!");
            System.out.println("MongoDatabase info is : " + database.getName());
    
            // 检索集合
            MongoCollection<Document> collection = database.getCollection("lizhengi_test_3");
            System.out.println("chose collection : " + collection.getNamespace());
            // 删除集合
            collection.drop();
            System.out.println("drop collection : " + collection.getNamespace());
    
            // 检索集合列表
            for (String name : database.listCollectionNames()) {
        
                System.out.println(name);
            }
        }
    }

运行 Main 函数，返回以下结果：

> Credentials ::MongoCredential\{mechanism=null, userName=‘lizhengi’, source=‘lizhengi’, password=, mechanismProperties=\}  
> Connect to database successfully!  
> MongoDatabase info is : lizhengi  
> chose collection : lizhengi.lizhengi\_test\_3
> 
> drop collection : lizhengi.lizhengi\_test\_3  
> lizhengi  
> lizhengi\_test\_2