当Spring遇见MongoDB，五分钟搞定CRUD

一、引入相关依赖

<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>4.11</version>
</dependency>

<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.1.1</version>
</dependency>

<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>4.3.4.RELEASE</version>
</dependency>

<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-mongodb</artifactId>
<version>1.9.5.RELEASE</version>
</dependency>

</dependencies>

二、配置MongoDB连接

spring官网提供了很多种配置方式 spring-mongo-reference

这是其中一种

package me.sclove.admin.config;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.mongodb.core.MongoClientFactoryBean;
import org.springframework.data.mongodb.core.MongoOperations;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.repository.config.EnableMongoRepositories;

import com.mongodb.Mongo;

@Configuration
public class MongoConfig {

@Bean
public MongoClientFactoryBean mongo(){
MongoClientFactoryBean factoryBean = new MongoClientFactoryBean();
factoryBean.setHost("localhost"); // 数据库地址
factoryBean.setPort(27017); // 端口
return factoryBean;
}

@Bean
public MongoOperations mongoTemplate(Mongo mongo){
// 操作Mongo的模板类，提供了非常纯粹的oo操作数据库的api
return new MongoTemplate(mongo, "dbtest"); // dbtest 为数据库名
}

}

三、编写测试类

①测试实体类

public class Person {

private String id;
private String name;
private int age;

public Person(String name, int age) {
this.name = name;
this.age = age;
}

public String getId() {
return id;
}

public String getName() {
return name;
}

public int getAge() {
return age;
}

@Override
public String toString() {
return "Person [id=" + id + ", name=" + name + ", age=" + age + "]";
}
}

②Test类

- insert

@Test
public void insert() {
AnnotationConfigApplicationContext a = new AnnotationConfigApplicationContext(
MongoConfig.class);
MongoOperations mongoOps = a.getBean(MongoOperations.class);
Person person = new Person("white", 23);
// 单条插入
mongoOps.insert(person);
List<Person> persons = new ArrayList<Person>();
for (int i = 1; i <= 20; i++) {
persons.add(new Person("white" + i + "号", 20 + i));
}
// 批量插入
mongoOps.insertAll(persons);
a.close();
}

一行代码搞定了Mongo的插入操作，这里我们并没有设置Mongo的集合名，只是传入了一个实体对象，初步猜想MongoOperations 模板类应该是把实体类的类名或者全类名作为了集合的名称，用一个Mongo GUI工具打开数据库



可以看到，基本印证了猜想，这里MongoOperations 把类名小写之后作为了Mongo集合的名称，而把当前类的全类名作为了一个字段存储到了数据库中

query

为了方便操作

// 静态导入

import static org.springframework.data.mongodb.core.query.Criteria.where;

import static org.springframework.data.mongodb.core.query.Update.update;

@Test
public void query() {
AnnotationConfigApplicationContext a = new AnnotationConfigApplicationContext(
MongoConfig.class);
MongoOperations mongoOps = a.getBean(MongoOperations.class);
// 查询匹配条件的第一条数据
Person findOne = mongoOps.findOne(new Query(where("name").is("white")), Person.class);
System.out.println(findOne);
// 查询所有记录
List<Person> all = mongoOps.findAll(Person.class);
System.out.println(all);
// 查询age >= 25 and age < 30
Query query = new Query(where("age").gte(25).lt(30));
List<Person> findByCondition = mongoOps.find(query , Person.class);
System.out.println(findByCondition);

// 原生命令方式
BasicQuery bq =new BasicQuery("{name:'white'}");

Person findOne2 = mongoOps.findOne(bq, Person.class);
System.out.println(findOne2);

a.close();
}

delete

@Test
public void delete() {
AnnotationConfigApplicationContext a = new AnnotationConfigApplicationContext(
MongoConfig.class);
MongoOperations mongoOps = a.getBean(MongoOperations.class);
// 删除age>=25的所有记录
WriteResult remove = mongoOps.remove(new Query(where("age").gte(25)),Person.class);

// 查出第一条匹配的记录并把这条记录删除 阅后即焚
Person findAndRemove = mongoOps.findAndRemove(new Query(where("name").is("white")), Person.class);
System.out.println(findAndRemove);
// 按对象删除
Person p = mongoOps.findOne(new Query(where("age").is(22)), Person.class);
mongoOps.remove(p);
// 删除集合
mongoOps.dropCollection(Person.class);
a.close();
}

update

@Test
public void updateTest() {
AnnotationConfigApplicationContext a = new AnnotationConfigApplicationContext(
MongoConfig.class);
MongoOperations mongoOps = a.getBean(MongoOperations.class);
// 更新一条
mongoOps.updateFirst(new Query(where("age").is(23)), update("name","white小哥"), Person.class);
// 更新多条
mongoOps.updateMulti(new Query(where("age").lte(23)), update("name","white大哥"), Person.class);
a.close();
}