在上一篇教程中，我们学习了如何使用Mongodb 的JAVA API对Mongodb进行相关的数据库操作，在本文中，将学习使用Spring for Mongodb去简化对Mongodb的操作。
安装Spring for Mongodb
Spring项目为方便对Mongodb的操作，建立了spring-data的子项目，地址在：
http://www.springsource.org/spring-data/mongodb，目前版本是1.0.0M2阶段，已支持对Mongodb的一系列基本操作。我们先从http://www.springsource.org/spring-data/mongodb中下载相关的包：spring-data-document-1.0.0.M2.zip，下载解压后，将解压后的四个JAR文件放到工程路径的lib库中，本文中还将使用Spring 3.0.4的版本，请读者自行下载配置。
Spring Mongodb的配置
目前，可以有两种方式对Spring mongodb进行配置。第一种是使用Spring 3中的注解，另外一种是使用传统的XML配置。下面分别进行讲解：
使用Spring 3中的注解
首先在配置类中，要继承AbstractMongoConfiguration类，代码如下：
package com.mkyong.config;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.document.mongodb.MongoTemplate;
import org.springframework.data.document.mongodb.config.AbstractMongoConfiguration;
import com.mongodb.Mongo;
/**
* Spring MongoDB configuration file
*
*/
@Configuration
public class SpringMongoConfig extends AbstractMongoConfiguration {
@Override
public @Bean Mongo mongo() throws Exception {
return new Mongo("localhost");
}
@Override
public @Bean MongoTemplate mongoTemplate() throws Exception {
return new MongoTemplate(mongo(),"yourdb","yourCollection");
}
}
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.document.mongodb.MongoTemplate;
import org.springframework.data.document.mongodb.config.AbstractMongoConfiguration;
import com.mongodb.Mongo;
/**
* Spring MongoDB configuration file
*
*/
@Configuration
public class SpringMongoConfig extends AbstractMongoConfiguration {
@Override
public @Bean Mongo mongo() throws Exception {
return new Mongo("localhost");
}
@Override
public @Bean MongoTemplate mongoTemplate() throws Exception {
return new MongoTemplate(mongo(),"yourdb","yourCollection");
}
}
这里，引入了MongoTemplate模版类，并且使用对连接数据库的地址，数据库名和collection进行了初始化。
在调用Spring Mongodb配置时，只需要在需要使用的类中调用AnnotationConfigApplicationContext，传入刚才配置好的SpringMongoConfig类即可。如下代码所示：
ApplicationContext
ctx = new AnnotationConfigApplicationContext(SpringMongoConfig. class);
MongoOperations
mongoOperation = (MongoOperations)ctx.getBean("mongoTemplate");
ctx = new AnnotationConfigApplicationContext(SpringMongoConfig. class);
MongoOperations
mongoOperation = (MongoOperations)ctx.getBean("mongoTemplate");
当获得了mongoOperation对象的实例后，即可进行对mongodb的相关操作。
使用XML配置文件
使用XML配置文件的方法如下：
<? xml version="1.0" encoding="UTF-8" ?>
< beans xmlns ="http://www.springframework.org/schema/beans"
xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context ="http://www.springframework.org/schema/context"
xmlns:mongo ="http://www.springframework.org/schema/data/mongo"
xsi:schemaLocation ="http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/data/mongo
http://www.springframework.org/schema/data/mongo/spring-mongo-1.0.xsd
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd" >
<!-- Default bean name is 'mongo' -->
< mongo:mongo host ="localhost" port ="27017" />
< bean id ="mongoTemplate"
class ="org.springframework.data.document.mongodb.MongoTemplate" >
< constructor-arg ref ="mongo" />
< constructor-arg name ="databaseName" value ="yourdb" />
< constructor-arg name ="defaultCollectionName" value ="yourCollection" />
</ bean >
<!-- To translate any MongoExceptions thrown in @Repository annotated classes -->
< context:annotation-config />
</ beans >
< beans xmlns ="http://www.springframework.org/schema/beans"
xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context ="http://www.springframework.org/schema/context"
xmlns:mongo ="http://www.springframework.org/schema/data/mongo"
xsi:schemaLocation ="http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context-3.0.xsd
http://www.springframework.org/schema/data/mongo
http://www.springframework.org/schema/data/mongo/spring-mongo-1.0.xsd
http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans-3.0.xsd" >
<!-- Default bean name is 'mongo' -->
< mongo:mongo host ="localhost" port ="27017" />
< bean id ="mongoTemplate"
class ="org.springframework.data.document.mongodb.MongoTemplate" >
< constructor-arg ref ="mongo" />
< constructor-arg name ="databaseName" value ="yourdb" />
< constructor-arg name ="defaultCollectionName" value ="yourCollection" />
</ bean >
<!-- To translate any MongoExceptions thrown in @Repository annotated classes -->
< context:annotation-config />
</ beans >
注意这里引用相关的命名空间xmlns:mongo="http://www.springframework.org/schema/data/mongo"
，并且在名为mongoTemplate中注入相关的数据库地址，数据库名即可，使用方法如下：
ApplicationContext ctx = new GenericXmlApplicationContext("mongo-config.xml");
使用Spring Mongodb实现增删改查操作
下面通过实例讲解如何使用Spring Mongodb实现增删改查操作，假设我们现在有一个实
体类user如下：
package com.mkyong.user;
public class User {
private String id;
private String firstname;
private String lastname;
private int age;
// getter and setter methods
}
public class User {
private String id;
private String firstname;
private String lastname;
private int age;
// getter and setter methods
}
接下来，我们看具体的操作代码，如下，这里假设要将user类保存到名为userprofile的数据集中。
package com.mkyong.core;
import java.util.List;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.support.GenericXmlApplicationContext;
import org.springframework.data.document.mongodb.MongoOperations;
import org.springframework.data.document.mongodb.query.Criteria;
import org.springframework.data.document.mongodb.query.Query;
import org.springframework.data.document.mongodb.query.Update;
import com.mkyong.config.SpringMongoConfig;
import com.mkyong.user.User;
public class App
{
public static void main( String[] args )
{
ApplicationContext ctx = new AnnotationConfigApplicationContext(SpringMongoConfig. class);
MongoOperations mongoOperation = (MongoOperations)ctx.getBean("mongoTemplate");
User user = new User("1001", "yong", "mook kim", 30);
// 保存
mongoOperation.save("userprofile",user);
// 查找
User savedUser = mongoOperation.findOne("userprofile",
new Query(Criteria.where("id").is("1001")),
User. class);
System.out.println("savedUser : " + savedUser);
// 更新
mongoOperation.updateFirst("userprofile",
new Query(Criteria.where("firstname").is("yong")),
Update.update("lastname", "new lastname"));
User updatedUser = mongoOperation.findOne("userprofile",
new Query(Criteria.where("id").is("1001")),
User. class);
System.out.println("updatedUser : " + updatedUser);
// 删除
mongoOperation.remove("userprofile",
new Query(Criteria.where("id").is("1001")),
User. class);
// 显示当前列表
List<User> listUser =
mongoOperation.getCollection("userprofile", User. class);
System.out.println("Number of user = " + listUser.size());
}
}
import java.util.List;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.context.support.GenericXmlApplicationContext;
import org.springframework.data.document.mongodb.MongoOperations;
import org.springframework.data.document.mongodb.query.Criteria;
import org.springframework.data.document.mongodb.query.Query;
import org.springframework.data.document.mongodb.query.Update;
import com.mkyong.config.SpringMongoConfig;
import com.mkyong.user.User;
public class App
{
public static void main( String[] args )
{
ApplicationContext ctx = new AnnotationConfigApplicationContext(SpringMongoConfig. class);
MongoOperations mongoOperation = (MongoOperations)ctx.getBean("mongoTemplate");
User user = new User("1001", "yong", "mook kim", 30);
// 保存
mongoOperation.save("userprofile",user);
// 查找
User savedUser = mongoOperation.findOne("userprofile",
new Query(Criteria.where("id").is("1001")),
User. class);
System.out.println("savedUser : " + savedUser);
// 更新
mongoOperation.updateFirst("userprofile",
new Query(Criteria.where("firstname").is("yong")),
Update.update("lastname", "new lastname"));
User updatedUser = mongoOperation.findOne("userprofile",
new Query(Criteria.where("id").is("1001")),
User. class);
System.out.println("updatedUser : " + updatedUser);
// 删除
mongoOperation.remove("userprofile",
new Query(Criteria.where("id").is("1001")),
User. class);
// 显示当前列表
List<User> listUser =
mongoOperation.getCollection("userprofile", User. class);
System.out.println("Number of user = " + listUser.size());
}
}
输出结果如下：
savedUser : User [id=1001, firstname=yong, lastname=mook kim, age=30]
updatedUser : User [id=1001, firstname=yong, lastname= new lastname, age=30]
Number of user = 0
updatedUser : User [id=1001, firstname=yong, lastname= new lastname, age=30]
Number of user = 0
Spring mongodb插入数据
下面详细讲解如何使用spring mongodb插入数据。在spring mongodb中，插入数据到
mongodb有如下几种方法：
User user = new User("...");
// 将user对象保存到"user"这个collection中
mongoOperation.save(user);
// 将user对象保存到"new collection"这个collection中
mongoOperation.save("new collection",user);
// 将user对象保存到"user"这个collection中
mongoOperation.insert(user);
// 将user对象保存到"new collection"这个collection中
mongoOperation.insert("new collection", user);
// 将user的对象列表(List)保存到"user"collection中去
mongoOperation.insertList(userInList);
// 将user的对象列表(List)保存到"new collection"collection中去
mongoOperation.insertList("new collection", userInList);
// 将user对象保存到"user"这个collection中
mongoOperation.save(user);
// 将user对象保存到"new collection"这个collection中
mongoOperation.save("new collection",user);
// 将user对象保存到"user"这个collection中
mongoOperation.insert(user);
// 将user对象保存到"new collection"这个collection中
mongoOperation.insert("new collection", user);
// 将user的对象列表(List)保存到"user"collection中去
mongoOperation.insertList(userInList);
// 将user的对象列表(List)保存到"new collection"collection中去
mongoOperation.insertList("new collection", userInList);
要注意的是,Spring mongodb中,当没有指定collection时,就会把对象保存到以对象命名的collection中。比如上例中的mongoOperation.insert(user)，由于没指定collection的名称，所以会把user对象保存到user这个新建立的collection中。
另外请注意其中的save和insert的区别。它们的区别为：
1)save意思是，当记录不存在时插入，或者是当记录已存在是更新，实际上就是saveorupdate的意思。
2) insert的意思是：当记录不存在时插入，而如果记录存在时则忽略，继续插入。
下面举例子说明：
package com.mkyong.core;
import java.util.ArrayList;
import java.util.List;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.data.document.mongodb.MongoOperations;
import org.springframework.data.document.mongodb.query.Criteria;
import org.springframework.data.document.mongodb.query.Query;
import com.mkyong.config.SpringMongoConfig;
import com.mkyong.user.User;
public class App {
public static void main(String[] args) {
ApplicationContext ctx = new AnnotationConfigApplicationContext(
SpringMongoConfig. class);
MongoOperations mongoOperation = (MongoOperations) ctx
.getBean("mongoTemplate");
// 新增一个user对象，并把它放到"ABC"这个collection中
System.out.println("Case 1...");
User userA = new User("1111", "user", "A", 99);
mongoOperation.save("ABC", userA);
// 查找刚插入的user对象
User userA1 = mongoOperation.findOne("ABC",
new Query(Criteria.where("id").is("1111")), User. class);
System.out.println(userA1);
// 插入新的user,放到userB这个collection中去
System.out.println("Case 2...");
User userB = new User("2222", "user", "B", 99);
mongoOperation.save(userB);
// 查找
User userB1 = mongoOperation.findOne(
new Query(Criteria.where("id").is("2222")), User. class);
System.out.println(userB1);
// 插入对象列表，放到arraylist中
System.out.println("Case 3...");
User userC = new User("3333", "user", "C", 99);
User userD = new User("4444", "user", "D", 99);
User userE = new User("5555", "user", "E", 99);
List<User> userList = new ArrayList<User>();
userList.add(userC);
userList.add(userD);
userList.add(userE);
mongoOperation.insertList("ABC-List", userList);
List<User> users = mongoOperation.find("ABC-List", new Query(Criteria
.where("firstname").is("user")), User. class);
for (User temp : users) {
System.out.println(temp);
}
}
}
import java.util.ArrayList;
import java.util.List;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.AnnotationConfigApplicationContext;
import org.springframework.data.document.mongodb.MongoOperations;
import org.springframework.data.document.mongodb.query.Criteria;
import org.springframework.data.document.mongodb.query.Query;
import com.mkyong.config.SpringMongoConfig;
import com.mkyong.user.User;
public class App {
public static void main(String[] args) {
ApplicationContext ctx = new AnnotationConfigApplicationContext(
SpringMongoConfig. class);
MongoOperations mongoOperation = (MongoOperations) ctx
.getBean("mongoTemplate");
// 新增一个user对象，并把它放到"ABC"这个collection中
System.out.println("Case 1...");
User userA = new User("1111", "user", "A", 99);
mongoOperation.save("ABC", userA);
// 查找刚插入的user对象
User userA1 = mongoOperation.findOne("ABC",
new Query(Criteria.where("id").is("1111")), User. class);
System.out.println(userA1);
// 插入新的user,放到userB这个collection中去
System.out.println("Case 2...");
User userB = new User("2222", "user", "B", 99);
mongoOperation.save(userB);
// 查找
User userB1 = mongoOperation.findOne(
new Query(Criteria.where("id").is("2222")), User. class);
System.out.println(userB1);
// 插入对象列表，放到arraylist中
System.out.println("Case 3...");
User userC = new User("3333", "user", "C", 99);
User userD = new User("4444", "user", "D", 99);
User userE = new User("5555", "user", "E", 99);
List<User> userList = new ArrayList<User>();
userList.add(userC);
userList.add(userD);
userList.add(userE);
mongoOperation.insertList("ABC-List", userList);
List<User> users = mongoOperation.find("ABC-List", new Query(Criteria
.where("firstname").is("user")), User. class);
for (User temp : users) {
System.out.println(temp);
}
}
}
输出结果如下：
Case 1...
User [id=1111, firstname=user, lastname=A, age=99]
Case 2...
User [id=2222, firstname=user, lastname=B, age=99]
Case 3...
User [id=3333, firstname=user, lastname=C, age=99]
User [id=4444, firstname=user, lastname=D, age=99]
User [id=5555, firstname=user, lastname=E, age=99]
User [id=1111, firstname=user, lastname=A, age=99]
Case 2...
User [id=2222, firstname=user, lastname=B, age=99]
Case 3...
User [id=3333, firstname=user, lastname=C, age=99]
User [id=4444, firstname=user, lastname=D, age=99]
User [id=5555, firstname=user, lastname=E, age=99]
更新Document
在mongodb中，可以使用save,updateFirst(),updateMulti()方法来进行更新，下面
是相关的例子
public class App {
public static void main(String[] args) {
ApplicationContext ctx = new AnnotationConfigApplicationContext(
SpringMongoConfig. class);
MongoOperations mongoOperation = (MongoOperations) ctx
.getBean("mongoTemplate");
User user = new User("1000", "user-first", "user-last", 17);
System.out.println("Case 1...by save()");
mongoOperation.save(user);
User userPrint1 = mongoOperation.findOne( new Query(Criteria.where("id").is("1000")), User. class);
System.out.println(userPrint1);
// 修改user对象的lastname
user.setLastname("new last name");
// 更新user对象
mongoOperation.save(user);
User userPrint2 = mongoOperation.findOne( new Query(Criteria.where("id")
.is("1000")), User. class);
System.out.println(userPrint2);
// Case 2 ... update firstname field, $set
System.out.println("Case 2...by updateFirst() - $set");
// 将id为1000的user对象的firstname属性的值更新为”new firstname”
mongoOperation.updateFirst("user",
new Query(Criteria.where("_id").is("1000")),
Update.update("firstname", "new first name"));
User userPrint3 = mongoOperation.findOne( new Query(Criteria.where("id")
.is("1000")), User. class);
System.out.println(userPrint3);
// 对id为1000的user的age加上10
System.out.println("Case 3...by updateFirst() - $inc");
Update updateAge = new Update();
updateAge.inc("age", 10);
mongoOperation.updateFirst("user",
new Query(Criteria.where("_id").is("1000")), updateAge);
User userPrint4 = mongoOperation.findOne( new Query(Criteria
.where("_id").is("1000")), User. class);
System.out.println(userPrint4);
}
}
public static void main(String[] args) {
ApplicationContext ctx = new AnnotationConfigApplicationContext(
SpringMongoConfig. class);
MongoOperations mongoOperation = (MongoOperations) ctx
.getBean("mongoTemplate");
User user = new User("1000", "user-first", "user-last", 17);
System.out.println("Case 1...by save()");
mongoOperation.save(user);
User userPrint1 = mongoOperation.findOne( new Query(Criteria.where("id").is("1000")), User. class);
System.out.println(userPrint1);
// 修改user对象的lastname
user.setLastname("new last name");
// 更新user对象
mongoOperation.save(user);
User userPrint2 = mongoOperation.findOne( new Query(Criteria.where("id")
.is("1000")), User. class);
System.out.println(userPrint2);
// Case 2 ... update firstname field, $set
System.out.println("Case 2...by updateFirst() - $set");
// 将id为1000的user对象的firstname属性的值更新为”new firstname”
mongoOperation.updateFirst("user",
new Query(Criteria.where("_id").is("1000")),
Update.update("firstname", "new first name"));
User userPrint3 = mongoOperation.findOne( new Query(Criteria.where("id")
.is("1000")), User. class);
System.out.println(userPrint3);
// 对id为1000的user的age加上10
System.out.println("Case 3...by updateFirst() - $inc");
Update updateAge = new Update();
updateAge.inc("age", 10);
mongoOperation.updateFirst("user",
new Query(Criteria.where("_id").is("1000")), updateAge);
User userPrint4 = mongoOperation.findOne( new Query(Criteria
.where("_id").is("1000")), User. class);
System.out.println(userPrint4);
}
}
结果为：
Case 1...by save()
User [id=1000, firstname=user-first, lastname=user-last, age=17]
User [id=1000, firstname=user-first, lastname= new last name, age=17]
Case 2...by updateFirst() - $set
User [id=1000, firstname= new first name, lastname= new last name, age=17]
Case 3...by updateFirst() - $inc
User [id=1000, firstname= new first name, lastname= new last name, age=27]
User [id=1000, firstname=user-first, lastname=user-last, age=17]
User [id=1000, firstname=user-first, lastname= new last name, age=17]
Case 2...by updateFirst() - $set
User [id=1000, firstname= new first name, lastname= new last name, age=17]
Case 3...by updateFirst() - $inc
User [id=1000, firstname= new first name, lastname= new last name, age=27]
此外，还支持使用updateMulti，updateMulti是将所有的对象进行更新，比如：
mongoOperation.updateMulti("user",
new Query(Criteria.where("firstname").is("yong")),
Update.update("age", 40));
new Query(Criteria.where("firstname").is("yong")),
Update.update("age", 40));
表示将所有firstname为yong的user对象的age属性全部更新为40。
查询Document
在spring mongodb中，可以使用findOne(),find()和getCollection()去查询mongodb，常见的用法如下：
User user = new User("...");
// 找到第一个id=1001的user对象
User user = mongoOperation.findOne("test", new Query(Criteria
.where("id").is("1001")), User. class);
// 从test集合中获得所有id<=1000并且age=21的user对象
List<User> users = mongoOperation.find("test", new Query(Criteria
.where("id").lte("2001").and("age").is(21)), User. class);
// 从test 集合中获得所有的user对象列表
List<User> users = mongoOperation.getCollection("test", User. class);
// 找到第一个id=1001的user对象
User user = mongoOperation.findOne("test", new Query(Criteria
.where("id").is("1001")), User. class);
// 从test集合中获得所有id<=1000并且age=21的user对象
List<User> users = mongoOperation.find("test", new Query(Criteria
.where("id").lte("2001").and("age").is(21)), User. class);
// 从test 集合中获得所有的user对象列表
List<User> users = mongoOperation.getCollection("test", User. class);
删除document
在spring mongodb中， 删除document使用remove方法，示例如下：
在spring mongodb中， 删除document使用remove方法，示例如下：
User user = new User("...");
// 删除user集合中的user对象
mongoOperation.remove(user);
// 删除test集合下的id=2的user对象
mongoOperation.remove("test", new Query(Criteria
.where("id").is("2")));
// 删除test集合下的，id=3的user对象，最后并且返回这个被删除的对象
User deletedUser = mongoOperation.findAndRemove("test",
new Query(Criteria.where("id").is("3")), User. class);
User user = new User("...");
// 删除user集合中的user对象
mongoOperation.remove(user);
// 删除test集合下的id=2的user对象
mongoOperation.remove("test", new Query(Criteria
.where("id").is("2")));
// 删除test集合下的，id=3的user对象，最后并且返回这个被删除的对象
User deletedUser = mongoOperation.findAndRemove("test",
new Query(Criteria.where("id").is("3")), User. class);