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。