MongoDB实验——在Java应用程序中操作 MongoDB 数据

在Java应用程序中操作 MongoDB 数据

1. 启动MongoDB Shell

2. 切换到admin数据库，使用root账户

3.开启Eclipse，创建Java Project项目，命名为MongoJava

File --> New --> Java Project

4.在MongoJava项目下新建包，包名为mongo

MongoJava右键 --> New --> mongo

5. 在mongo包下新建类，类名为mimalianjie

mongo右键 --> New --> Class

6. 添加项目依赖的jar包，右键单击MongoJava，选择Import

7. 选择General中的File System，点击Next

8. 选择存放mongo连接java的驱动程序的文件夹，并进行勾选Create top-level folder

9. 选中导入的文件夹中的mongo-java-driver-3.2.2.jar，右击选择Build Path中的Add to Build Path。

10. 连接数据库：编写代码，功能为连接Mongodb数据库。我们需要指定数据库名称，如果指定的数据库不存在，mongo会自动创建数据库

package mongo;

import java.util.ArrayList;

import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.MongoDatabase;

public class mimalianjie {
	public static void main(String[] args) {
		try {
			ServerAddress serverAddress = new ServerAddress("localhost",27017);
			ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
			addrs.add(serverAddress);
			
MongoCredential credential = MongoCredential.createScramSha1Credential("root", "admin", "strongs".toCharArray());
			ArrayList<MongoCredential> credentials = new
					ArrayList<MongoCredential>();
			credentials.add(credential);

			MongoClient mongoClient = new MongoClient(addrs,credentials);
			
			MongoDatabase mongoDatabase = mongoClient.getDatabase("databaseName");
			System.out.println("Connect to database successfully");
		} catch (Exception e) {
			System.err.println( e.getClass().getName() + ": " + e.getMessage() );
		}
	}

}

11. 创建集合：与上述步骤相同，在mongo包下新建类，类名为chuangjianjihe，编写代码，功能为在test库下创建集合mycol（使用com.mongodb.client.MongoDatabase类中的createCollection()来创建集合）

package mongo;

import java.util.ArrayList;

import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.MongoDatabase;

public class chuanjianjihe {
	public static void main(String[] args) {
		try {
			ServerAddress serverAddress = new ServerAddress("localhost",27017);
			ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
			addrs.add(serverAddress);
			
MongoCredential credential = MongoCredential.createScramSha1Credential("root","admin","strongs".toCharArray());
			ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
			credentials.add(credential);
			MongoClient mongoClient = new MongoClient(addrs,credentials);
			
			MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
			System.out.println("Connect to database successfully");
			
				mongoDatabase.createCollection("mycol");
				System.out.println("集合mycol创建成功");
		}catch (Exception e) {
			System.err.println( e.getClass().getName() + ": " + e.getMessage());
		}
	}

}

12. 在mongodb中进行验证

13. 获取集合：在mongo包下新建类，名为huoqujihe，并编写代码，功能为获取所需集合（使用com.mongodb.client.MongoDatabase类的 getCollection() 方法来获取一个集合）

package mongo;

import java.util.ArrayList;

import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;

public class huoqujihe {
	public static void main(String[] args) {
		try {
			ServerAddress serverAddress = new ServerAddress("localhost",27017);
			ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
			addrs.add(serverAddress);
			
			MongoCredential credential = MongoCredential.createScramSha1Credential("root","admin","strongs".toCharArray());
			ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
			credentials.add(credential);
			
			MongoClient mongoClient = new MongoClient(addrs,credentials);
			
			MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
			System.out.println("Connect to database successfully");
			MongoCollection<org.bson.Document> collection = mongoDatabase.getCollection("mycol");
			System.out.println("集合mycol选择成功");
		} catch (Exception e) {
			System.err.println( e.getClass().getName() + ": " + e.getMessage());
		}
	}

}

14.插入文档：在mongo包中新建类，名为charuwendang，功能为连接test库，选择mycol集合并向其中插入文档。（使用com.mongodb.client.MongoCollection类的insertMany()方法来插入一个文档）

package mongo;

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

import org.bson.Document;

import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;

public class charuwendang {
	public static void main (String[] args) {
		try {
			ServerAddress serverAddress = new ServerAddress("localhost",27017);
			ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
			addrs.add(serverAddress);
			
			MongoCredential credential = MongoCredential.createScramSha1Credential("root"
			,"admin","strongs".toCharArray());
			ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
			credentials.add(credential);
			
			MongoClient mongoClient = new MongoClient(addrs,credentials);
			
			MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
			System.out.println("Connect to database successfully");
			MongoCollection<org.bson.Document> collection = mongoDatabase.getCollection("mycol");
			System.out.println("集合mycol选择成功");
			
			Document document = new Document("name", "zhangyudashuju").
			append("description", "YXCX").
			append("likes", 100).
			append("location", "BJ");
			List<Document> documents = new ArrayList<Document>();
			documents.add(document);
			collection.insertMany(documents);
			System.out.println("文档插入成功");
		}catch(Exception e) {
			System.err.println( e.getClass().getName() + ": " + e.getMessage() );
		}
	}
}

15.在mongodb中进行查询验证

16. 检索文档：在mongo包中新建类，名为jiansuosuoyouwendang，功能为检索test库下，mycol集合中的所有文档（使用 com.mongodb.client.MongoCollection 类中的 find() 方法来获取集合中的所有文档）

package mongo;

import java.util.ArrayList;

import org.bson.Document;

import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
import com.mongodb.client.FindIterable;
import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoCursor;
import com.mongodb.client.MongoDatabase;

public class jiansuosuoyouwendang {
	public static void main( String args[] ){
		try{
		ServerAddress serverAddress = new ServerAddress("localhost",27017);
		ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
		addrs.add(serverAddress);
 
		MongoCredential credential = MongoCredential.createScramSha1Credential("root"
		,"admin", "strongs".toCharArray());
		ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
		credentials.add(credential);
		 
		MongoClient mongoClient = new MongoClient(addrs,credentials);
		 
		MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
		System.out.println("Connect to database successfully");
		MongoCollection<org.bson.Document> collection = mongoDatabase.getCollection("mycol");
		System.out.println("集合mycol选择成功");
		 
		FindIterable<Document> findIterable = collection.find();
		MongoCursor<Document> mongoCursor = findIterable.iterator();
		while(mongoCursor.hasNext()){
		System.out.println(mongoCursor.next());
			}
		}catch(Exception e){
			System.err.println( e.getClass().getName() + ": " + e.getMessage() );
		}
	}
}

17. 更新文档：在mongo包中新建类，名为gengxinwendang，功能为选择test库下mycol集合，将文档中的likes=100改为likes=200（使用 com.mongodb.client.MongoCollection 类中的updateMany()方法来更新集合中的文档）

package mongo;

import java.util.ArrayList;

import org.bson.Document;

import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
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 gengxinwendang {

	public static void main( String args[] ){
		try{
		ServerAddress serverAddress = new ServerAddress("localhost",27017);
			ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
			addrs.add(serverAddress);
		
			MongoCredential credential = MongoCredential.createScramSha1Credential("root"
					,"admin", "strongs".toCharArray());
			ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
			credentials.add(credential);
		
			MongoClient mongoClient = new MongoClient(addrs,credentials);
			
			MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
		 	System.out.println("Connect to database successfully");
		 	MongoCollection<org.bson.Document> collection = mongoDatabase.getCollection("mycol");
		 	System.out.println("集合mycol选择成功");
		
		collection.updateMany(Filters.eq("likes", 100), new Document("$set",new Document("likes",200)));
		
		FindIterable<Document> findIterable = collection.find();
		MongoCursor<Document> mongoCursor = findIterable.iterator();
		while(mongoCursor.hasNext()){
			System.out.println(mongoCursor.next());
		}
		
		}catch(Exception e){
			System.err.println( e.getClass().getName() + ": " + e.getMessage() );
		}
	}
}

18. 在mongodb中进行查询验证

19. 删除文档：在mongo包中新建类，名为sanchuwendang，功能为选择test库下mycol集合，删除所有符合条件（likes=200）的文档。（使用com.mongodb.DBCollection类中的findOne()方法来获取第一个文档，然后使用remove方法删除）

package mongo;

import java.util.ArrayList;

import org.bson.Document;

import com.mongodb.MongoClient;
import com.mongodb.MongoCredential;
import com.mongodb.ServerAddress;
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 shanchuwendang {
	public static void main( String args[] ){
		try{
		ServerAddress serverAddress = new ServerAddress("localhost",27017);
			ArrayList<ServerAddress> addrs = new ArrayList<ServerAddress>();
			addrs.add(serverAddress);
		
		
			MongoCredential credential = MongoCredential.createScramSha1Credential("root"
					,"admin", "strongs".toCharArray());
			ArrayList<MongoCredential> credentials = new ArrayList<MongoCredential>();
			credentials.add(credential);
		
		
			MongoClient mongoClient = new MongoClient(addrs,credentials);
		
		
			MongoDatabase mongoDatabase = mongoClient.getDatabase("test");
			System.out.println("Connect to database successfully");
			MongoCollection<org.bson.Document> collection = mongoDatabase.getCollection("mycol");
			System.out.println("集合mycol选择成功");
		
		//删除符合条件的第一个文档
		//collection.deleteOne(Filters.eq("likes", 200));
		//删除所有符合条件的文档
		collection.deleteMany (Filters.eq("likes", 200));
		//检索查看结果
		FindIterable<Document> findIterable = collection.find();
		MongoCursor<Document> mongoCursor = findIterable.iterator();
		while(mongoCursor.hasNext()){
			System.out.println(mongoCursor.next());
		}
		
		}catch(Exception e){
			System.err.println( e.getClass().getName() + ": " + e.getMessage() );
		}
	}
}

20. 在mongodb中进行查询验证

查询结果为空，证明文档已被删除。

至此，实验结束!