Java操作MongoDB

mongodb-driver

mongodb-driver是mongo官方推出的java连接mongoDB的驱动包，相当于JDBC驱动。
我们通过一个入门的案例来了解mongodb-driver的基本使用
引入pom依赖

<dependencies>
<dependency>
<groupId>org.mongodb</groupId>
<artifactId>mongodb‐driver</artifactId>
<version>3.6.3</version>
</dependency>
</dependencies>

查询全部记录

创建测试类

/**
* MongoDb入门小demo
*/
public class MongoDemo {
public static void main(String[] args) {
MongoClient client=new MongoClient("192.168.184.134");//创建连接
MongoDatabase spitdb = client.getDatabase("spitdb");//打开数据库
MongoCollection<Document> spit = spitdb.getCollection("spit");//
获取集合
FindIterable<Document> documents = spit.find();//查询记录获取文档集
合
for(Document document:documents){ //
System.out.println("内容："+  document.getString("content"));
System.out.println("用户ID:"+document.getString("userid"));
System.out.println("浏览量："+document.getInteger("visits"));
}
client.close();//关闭连接
}
}

条件查询

BasicDBObject对象：表示一个具体的记录，BasicDBObject实现了DBObject，是key-
value的数据结构，用起来和HashMap是基本一致的。
（1）查询userid为1013的记录

public class MongoDemo1 {
public static void main(String[] args) {
MongoClient client=new MongoClient("192.168.184.134");//创建连接
MongoDatabase spitdb = client.getDatabase("spitdb");//打开数据库
MongoCollection<Document> spit = spitdb.getCollection("spit");//
获取集合
BasicDBObject bson=new BasicDBObject("userid","1013");// 构建查询
条件
FindIterable<Document> documents = spit.find(bson);//查询记录获取结
果集合
for(Document document:documents){ //
System.out.println("内容："+  document.getString("content"));
System.out.println("用户ID:"+document.getString("userid"));
System.out.println("浏览量："+document.getInteger("visits"));
}
client.close();//关闭连接
}
}

（2）查询浏览量大于1000的记录

public class MongoDemo2 {
public static void main(String[] args) {
MongoClient client=new MongoClient("192.168.184.134");//创建连接
MongoDatabase spitdb = client.getDatabase("spitdb");//打开数据库
MongoCollection<Document> spit = spitdb.getCollection("spit");//
获取集合
BasicDBObject bson=new BasicDBObject("visits",new
BasicDBObject("$gt",1000) );// 构建查询条件

FindIterable<Document> documents = spit.find(bson);//查询记录获取结
果集合
for(Document document:documents){ //
System.out.println("内容："+  document.getString("content"));
System.out.println("用户ID:"+document.getString("userid"));
System.out.println("浏览量："+document.getInteger("visits"));
}
client.close();//关闭连接
}
}

插入数据

public class MongoDemo3 {
public static void main(String[] args) {
MongoClient client=new MongoClient("192.168.184.134");//创建连接
MongoDatabase spitdb = client.getDatabase("spitdb");//打开数据库
MongoCollection<Document> spit = spitdb.getCollection("spit");//
获取集合
Map<String,Object> map=new HashMap();
map.put("content","我要吐槽");
map.put("userid","9999");
map.put("visits",123);
map.put("publishtime",new Date());
Document document=new Document(map);
spit.insertOne(document);//插入数据
client.close();
}
}