MongoDB入门（7）- SpringDataMongoDB

入门

本文介绍如何应用SpringDataMongoDB操作实体和数据库，本文只介绍最基本的例子，复杂的例子在后面的文章中介绍。

SpringDataMongoDB简介

SpringDataMongoDB是spring data的一个子项目，用来封装对MongoDB的操作，现在最新的版本是1.6.1。（截至2015年1月18日）

The Spring Data MongoDB project provides integration with the MongoDB document database. Key functional areas of Spring Data MongoDB are a POJO centric model for interacting with a MongoDB DBCollection and easily writing a Repository style data access layer.

MongoDB是一个非关系型数据库，这里不详细介绍了。

SpringDataMongoDB有以下一些特点：

• Spring configuration support using Java based @Configuration classes or an XML namespace for a Mongo driver instance and replica sets.
• MongoTemplate helper class that increases productivity performing common Mongo operations. Includes integrated object mapping between documents and POJOs.
• Exception translation into Spring's portable Data Access Exception hierarchy
• Feature Rich Object Mapping integrated with Spring's Conversion Service
• Annotation based mapping metadata but extensible to support other metadata formats
• Persistence and mapping lifecycle events
• Low-level mapping using MongoReader/MongoWriter abstractions
• Java based Query, Criteria, and Update DSLs
• Automatic implementation of Repository interfaces including support for custom finder methods.
• QueryDSL integration to support type-safe queries.
• Cross-store persistance - support for JPA Entities with fields transparently persisted/retrieved using MongoDB
• Log4j log appender
• GeoSpatial integration
• Map-Reduce integration
• JMX administration and monitoring
• CDI support for repositories
• GridFS support

实体类定义

package com.chzhao.mongodbtest;

import org.springframework.data.annotation.Id;

public class Customer {
	@Id
    private String id;

    public String getId() {
		return id;
	}

	public void setId(String id) {
		this.id = id;
	}

	public String getFirstName() {
		return firstName;
	}

	public void setFirstName(String firstName) {
		this.firstName = firstName;
	}

	public String getLastName() {
		return lastName;
	}

	public void setLastName(String lastName) {
		this.lastName = lastName;
	}

	private String firstName;
    private String lastName;

    public Customer() {}

    public Customer(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }

    @Override
    public String toString() {
        return String.format(
                "Customer[id=%s, firstName='%s', lastName='%s']",
                id, firstName, lastName);
    }
}

操作类定义

package com.chzhao.mongodbtest;

import java.util.List;

import org.springframework.data.mongodb.repository.MongoRepository;

public interface CustomerRepository extends MongoRepository<Customer, String> {

	public Customer findByFirstName(String firstName);

	public List<Customer> findByLastName(String lastName);

	public long deleteByFirstName(String firstName);

	public long countByLastName(String lastName);
}

调用方法

package com.chzhao.mongodbtest;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.EnableAutoConfiguration;

EnableAutoConfiguration
public class Application implements CommandLineRunner {

	@Autowired
	private CustomerRepository repository;

	public static void main(String[] args) {
		SpringApplication.run(Application.class, args);
	}

	public void run(String... args) throws Exception {

		for (int i = 0; i < 10000; i++) {
			repository.save(new Customer(i + "", "zhao"));
		}
		long cou = repository.countByLastName("zhao");
		System.out.println(cou);

		System.out.println("Customers found with findAll():");
		System.out.println("-------------------------------");
		for (Customer customer : repository.findAll()) {
			System.out.println(customer);
		}
		System.out.println();
		repository.deleteByFirstName("zhao");

		// fetch an individual customer
		System.out.println("Customer found with findByFirstName('Alice'):");
		System.out.println("--------------------------------");
		System.out.println(repository.findByFirstName("Alice"));

		System.out.println("Customers found with findByLastName('Smith'):");
		System.out.println("--------------------------------");
		for (Customer customer : repository.findByLastName("zhao")) {
			System.out.println(customer);
		}

	}

}

pom.xml

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>

	<groupId>com.chzhao</groupId>
	<artifactId>mongodbtest</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<packaging>jar</packaging>

	<properties>
		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
	</properties>

	<dependencies>
		<dependency>
			<groupId>junit</groupId>
			<artifactId>junit</artifactId>
			<version>3.8.1</version>
			<scope>test</scope>
		</dependency>
		<dependency>
			<groupId>org.mongodb</groupId>
			<artifactId>mongo-java-driver</artifactId>
			<version>2.11.4</version>
		</dependency>
		<dependency>
			<groupId>org.springframework.data</groupId>
			<artifactId>spring-data-mongodb</artifactId>
			<version>1.6.1.RELEASE</version>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-mongodb</artifactId>
			<version>1.1.10.RELEASE</version>
		</dependency>

	</dependencies>
</project>

MongoOperations介绍

MongoOperations是一个很强大的接口，有了这个接口，基本上什么都搞定了。

其介绍

Interface that specifies a basic set of MongoDB operations. Implemented by {@link MongoTemplate}. Not often used but a useful option for extensibility and testability (as it can be easily mocked, stubbed, or be the target of a JDK proxy

直接上代码

实体类

package com.chzhao.mongodbtest;

import java.util.Date;

import org.springframework.data.annotation.Id;

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

	private Date birth;

	@Id
	private String id;

	public Date getBirth() {
		return birth;
	}

	public void setBirth(Date birth) {
		this.birth = birth;
	}

	public String getId() {
		return id;
	}

	public void setId(String id) {
		this.id = id;
	}

	private String name;

	public String getName() {
		return name;
	}

	public void setName(String name) {
		this.name = name;
	}

	public int getAge() {
		return age;
	}

	public void setAge(int age) {
		this.age = age;
	}

	private int age;
}

操作类

package com.chzhao.mongodbtest;

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

import java.util.Date;
import java.util.List;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.joda.time.DateTime;
import org.springframework.data.mongodb.core.MongoOperations;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.query.Query;

import com.mongodb.Mongo;

public class MongoApp {
	private static final Log log = LogFactory.getLog(MongoApp.class);

	public static void main(String[] args) throws Exception {

		MongoOperations mongoOps = new MongoTemplate(new Mongo(), "zch");
		mongoOps.dropCollection(Person.class);
		mongoOps.remove(new Query(where("name").is("zhao")), Person.class);
		DateTime zhaoBirth = new DateTime(1985, 12, 13, 18, 23, 55);
		DateTime liangBirth = new DateTime(1986, 12, 13, 18, 23, 55);
		mongoOps.insert(new Person("zhao", 34, zhaoBirth.toDate()));
		mongoOps.insert(new Person("liang", 24, liangBirth.toDate()));

		List<Person> pList = mongoOps.find(new Query(where("name").is("zhao")),
				Person.class);
		for (Person p : pList) {
			log.info(p.getName() + p.getAge());
		}
		DateTime someday = new DateTime(1986, 1, 13, 18, 23, 55);
		List<Person> pList1 = mongoOps.find(new Query(where("birth").lt(someday)), Person.class);
		for (Person p : pList1) {
			log.info(p.getName() + p.getAge());
		}

	}
}

这个Query类似lambda表达式，能做很多事情，很赞。