本文介绍的是基于Pojo方式增删改查mongodb的例子，如果需要用document原始client API进行增删改查，参考我的另一篇博文《mongodb-4.4.10版本在Java中，基于Document的增删改查例子》
首先加入maven依赖：
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-mongodb</artifactId>
<version>3.2.6</version>
</dependency>
Tips:
1.spring-data-mongodb一般使用pojo的开发方式
2.spring-data-mongodb，需要spring5.0版本以上才推荐使用Java代码
先定义一个Pojo
import org.springframework.data.mongodb.core.mapping.Document;
@Document(collection="users")
public class User {
private ObjectId id;
private String username;
}增删改查demo
import static com.mongodb.client.model.Updates.*;
import static com.mongodb.client.model.Filters.*;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.function.Consumer;
import com.mongodb.WriteConcern;
import org.bson.Document;
import org.bson.codecs.configuration.CodecRegistries;
import org.bson.codecs.configuration.CodecRegistry;
import org.bson.codecs.pojo.PojoCodecProvider;
import org.bson.conversions.Bson;
import org.junit.Before;
import org.junit.Test;
import cn.enjoy.entity.Address;
import cn.enjoy.entity.Favorites;
import cn.enjoy.entity.User;
import com.mongodb.MongoClient;
import com.mongodb.MongoClientOptions;
import com.mongodb.ServerAddress;
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 com.mongodb.client.result.DeleteResult;
import com.mongodb.client.result.UpdateResult;
//原生java驱动 Pojo的操作方式
public class QuickStartJavaPojoTest {
private MongoDatabase db;
private MongoCollection<User> doc;
private MongoClient client;
@Before
public void init(){
//编解码器的list
List<CodecRegistry> codecResgistes = new ArrayList<>();
//list加入默认的编解码器集合
codecResgistes.add(MongoClient.getDefaultCodecRegistry());
//生成一个pojo的编解码器
CodecRegistry pojoCodecRegistry = CodecRegistries.
fromProviders(PojoCodecProvider.builder().automatic(true).build());
//list加入pojo的编解码器
codecResgistes.add(pojoCodecRegistry);
//通过编解码器的list生成编解码器注册中心
CodecRegistry registry = CodecRegistries.fromRegistries(codecResgistes);
//把编解码器注册中心放入MongoClientOptions
//MongoClientOptions相当于连接池的配置信息
MongoClientOptions build = MongoClientOptions.builder().
codecRegistry(registry).build();
ServerAddress serverAddress = new ServerAddress("localhost", 27017);
client = new MongoClient(serverAddress, build);
db =client.getDatabase("lison");
doc = db.getCollection("users",User.class);
}
@Test
public void insertDemo(){
User user = new User();
user.setUsername("cang");
user.setCountry("USA");
user.setAge(20);
user.setLenght(1.77f);
user.setSalary(new BigDecimal("6265.22"));
//添加“address”子文档
Address address1 = new Address();
address1.setaCode("411222");
address1.setAdd("sdfsdf");
user.setAddress(address1);
//添加“favorites”子文档，其中两个属性是数组
Favorites favorites1 = new Favorites();
favorites1.setCites(Arrays.asList("东莞","东京"));
favorites1.setMovies(Arrays.asList("西游记","一路向西"));
user.setFavorites(favorites1);
User user1 = new User();
user1.setUsername("chen");
user1.setCountry("China");
user1.setAge(30);
user1.setLenght(1.77f);
user1.setSalary(new BigDecimal("6885.22"));
Address address2 = new Address();
address2.setaCode("411000");
address2.setAdd("我的地址2");
user1.setAddress(address2);
Favorites favorites2 = new Favorites();
favorites2.setCites(Arrays.asList("珠海","东京"));
favorites2.setMovies(Arrays.asList("东游记","一路向东"));
user1.setFavorites(favorites2);
//使用insertMany插入多条数据
doc.insertMany(Arrays.asList(user,user1));
}
@Test
public void testFind(){
final List<User> ret = new ArrayList<>();
Consumer<User> printDocument = new Consumer<User>() {
@Override
public void accept(User t) {
System.out.println(t.toString());
ret.add(t);
}
};
//select * from users where favorites.cites has "东莞"、"东京"
//db.users.find({ "favorites.cites" : { "$all" : [ "东莞" , "东京"]}})
Bson all = all("favorites.cites", Arrays.asList("东莞","东京"));//定义数据过滤器，喜欢的城市中要包含"东莞"、"东京"
FindIterable<User> find = doc.find(all);
find.forEach(printDocument);
System.out.println("------------------>"+String.valueOf(ret.size()));
ret.removeAll(ret);
//select * from users where username like '%s%' and (contry= English or contry = USA)
// db.users.find({ "$and" : [ { "username" : { "$regex" : ".*c.*"}} , { "$or" : [ { "country" : "English"} , { "country" : "USA"}]}]})
String regexStr = ".*c.*";
Bson regex = regex("username", regexStr);//定义数据过滤器，username like '%s%'
Bson or = or(eq("country","English"),eq("country","USA"));//定义数据过滤器，(contry= English or contry = USA)
FindIterable<User> find2 = doc.find(and(regex,or));
find2.forEach(printDocument);
System.out.println("------------------>"+String.valueOf(ret.size()));
}
@Test
public void testUpdate(){
//update users set age=6 where username = 'lison'
//db.users.updateMany({ "username" : "lison"},{ "$set" : { "age" : 6}},true)
Bson eq = eq("username", "lison");//定义数据过滤器，username = 'lison'
Bson set = set("age", 8);//更新的字段.来自于Updates包的静态导入
UpdateResult updateMany = doc.updateMany(eq, set);
System.out.println("------------------>"+String.valueOf(updateMany.getModifiedCount()));//打印受影响的行数
//update users set favorites.movies add "小电影2 ", "小电影3" where favorites.cites has "东莞"
//db.users.updateMany({ "favorites.cites" : "东莞"}, { "$addToSet" : { "favorites.movies" : { "$each" : [ "小电影2 " , "小电影3"]}}},true)
Bson eq2 = eq("favorites.cites", "东莞");//定义数据过滤器，favorites.cites has "东莞"
Bson addEachToSet = addEachToSet("favorites.movies", Arrays.asList( "小电影2 ", "小电影3"));//更新的字段.来自于Updates包的静态导入
UpdateResult updateMany2 = doc.updateMany(eq2, addEachToSet);
System.out.println("------------------>"+String.valueOf(updateMany2.getModifiedCount()));
}
@Test
public void testDelete(){
//delete from users where username = ‘lison’
//db.users.deleteMany({ "username" : "lison"} )
Bson eq = eq("username", "lison");//定义数据过滤器，username='lison'
DeleteResult deleteMany = doc.deleteMany(eq);
System.out.println("------------------>"+String.valueOf(deleteMany.getDeletedCount()));//打印受影响的行数
//delete from users where age >8 and age <25
//db.users.deleteMany({"$and" : [ {"age" : {"$gt": 8}} , {"age" : {"$lt" : 25}}]})
Bson gt = gt("age",8);//定义数据过滤器，age > 8，所有过滤器的定义来自于Filter这个包的静态方法，需要频繁使用所以静态导入
Bson lt = lt("age",25);//定义数据过滤器，age < 25
Bson and = and(gt,lt);//定义数据过滤器，将条件用and拼接
DeleteResult deleteMany2 = doc.deleteMany(and);
System.out.println("------------------>"+String.valueOf(deleteMany2.getDeletedCount()));//打印受影响的行数
}
}end.
