MongoDB现在用的非常非常多,如何和Spring整合也是经常碰到的问题。
Spring提供了MongoTemplate
这样一个模板类的实现方法,简化了具体操作。
下面讲一下具体实现:
添加依赖
<dependency>
<groupId>org.springframework.data</groupId>
<artifactId>spring-data-mongodb</artifactId>
<version>1.10.3.RELEASE</version>
</dependency>
其余Spring相关的忽略
Spring的配置applicationContext-mongo.xml
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:util="http://www.springframework.org/schema/util"
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/util http://www.springframework.org/schema/util/spring-util.xsd
http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd
http://www.springframework.org/schema/data/mongo http://www.springframework.org/schema/data/mongo/spring-mongo.xsd">
<context:property-placeholder
ignore-unresolvable="true" location="classpath:/mongodb.properties"/>
<mongo:mongo-client id="mongoClient" host="${mongo.host}" port="${mongo.port}">
<!-- credentials="${mongo.user}:${mongo.pwd}@${mongo.defaultDbName}"-->
</mongo:mongo-client>
<mongo:db-factory id="mongoDbFactory"
dbname="${mongo.database}"
mongo-ref="mongoClient"/>
<!-- 默认Mongodb类型映射 -->
<bean id="defaultMongoTypeMapper" class="org.springframework.data.mongodb.core.convert.DefaultMongoTypeMapper">
<constructor-arg name="typeKey">
<!-- 这里设置为空,可以把 spring data mongodb 多余保存的_class字段去掉 -->
<null/>
</constructor-arg>
</bean>
<mongo:repositories base-package="com.critc.mongo"/>
<!-- 自动扫描以下包的有Doucment注解的类 -->
<mongo:mapping-converter id="mappingConverter" base-package="com.critc.mongo.model"
type-mapper-ref="defaultMongoTypeMapper">
</mongo:mapping-converter>
<!-- Mongodb的模板 -->
<bean id="mongoTemplate" class="org.springframework.data.mongodb.core.MongoTemplate">
<constructor-arg name="mongoDbFactory" ref="mongoDbFactory"/>
<constructor-arg name="mongoConverter" ref="mappingConverter"/>
</bean>
</beans>
mongo:mongo-client
是定义MongoDB的客户端连接,需要host
和port
参数,如果需要账号密码的话,需要增加credentials
配置
mongo:db-factory
配置连接工厂,指定具体的连接数据库,本例默认为test
defaultMongoTypeMapper
默认Mongodb类型映射
mongo:mapping-converter
MongoDB的实体映射
mongoTemplate
这是最主要的,定义模板类,依赖连接工厂和实体映射
这里举一个article的增删改查的例子。
相关实体Article.java
@Document(collection = "article_info")
public class Article {
@Id
private String id;//id
@Field("title")
private String title;//标题
@Field("url")
private String url;//链接
@Field("author")
private String author;//作者
@Field("tags")
private List<String> tags;//tag 标签
@Field("visit_count")
private Long visitCount;//访问次数
@Field("add_time")
private Date addTime;//添加时间
// get set方法省略
@Document(collection = "article_info")
这个注解和Hibernate的注解Entiry
非常相似,就是定义一个文档,对象MongoDB存储的Collection的名称是article_info
@Id
指该字段是主键,不能缺少
@Field("add_time")指该字段映射MongoDB的实际字段,如果一致可以省略
ArticleRepository实际访问接口
@Repository("ArticleRepository")
public interface ArticleRepository extends PagingAndSortingRepository<Article, String> {
//分页查询
public Page<Article> findAll(Pageable pageable);
//根据author查询
public List<Article> findByAuthor(String author);
//根据作者和标题查询
public List<Article> findByAuthorAndTitle(String author, String title);
//忽略参数大小写
public List<Article> findByAuthorIgnoreCase(String author);
//忽略所有参数大小写
public List<Article> findByAuthorAndTitleAllIgnoreCase(String author, String title);
//排序
public List<Article> findByAuthorOrderByVisitCountDesc(String author);
public List<Article> findByAuthorOrderByVisitCountAsc(String author);
//自带排序条件
public List<Article> findByAuthor(String author, Sort sort);
}
Spring的data repository封装了一套增删改查的方法,就和JPA实现的一样,ArticleRepository
继承PagingAndSortingRepository
,就集成了常用的增删改查方法,比如save、findOne、exists、findAll、delete等等,可以采用默认实现方式来完成常用的增删改查操作。
测试上述各个方法ArticleRepositoryTest.java
@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"classpath*:applicationContext-mongo.xml"})
public class ArticleRepositoryTest {
@Autowired
private ArticleRepository articleRepository;
/**
* 新增记录
*/
@Test
public void add() {
//增加一条记录
Article article = new Article();
article.setId("1");
article.setTitle("MongoTemplate的基本使用");
article.setAuthor("kcy");
article.setUrl("http://jianshu.com/");
article.setTags(Arrays.asList("java", "mongodb", "spring"));
article.setVisitCount(0L);
article.setAddTime(new Date());
articleRepository.save(article);
//批量添加
List<Article> articles = new ArrayList<>(10);
for (int i = 0; i < 10; i++) {
Article article2 = new Article();
article2.setId(String.valueOf(i + 1));
article2.setTitle("MongoTemplate的基本使用");
article2.setAuthor("kcy");
article2.setUrl("http://jianshu.com" + i);
article2.setTags(Arrays.asList("java", "mongodb", "spring"));
article2.setVisitCount(0L);
article2.setAddTime(new Date());
articles.add(article2);
}
articleRepository.save(articles);
}
/**
* 修改记录,修改id为1的访问次数+1
*/
@Test
public void update() {
Article article = articleRepository.findOne("1");
article.setVisitCount(article.getVisitCount() + 1);
articleRepository.save(article);
}
/**
* 批量修改,查看author为kcy的统一修改为kcy2
*/
@Test
public void batchUpdate() {
List<Article> articles = articleRepository.findByAuthor("kcy");
articles.forEach(article -> {
article.setAuthor("kcy2");
});
articleRepository.save(articles);
}
/**
* 删除记录,删除id为10的
*/
@Test
public void delete() {
Article article = articleRepository.findOne("10");
articleRepository.delete(article);
}
@Test
public void batchDelete() {
List<Article> articles = articleRepository.findByAuthor("kcy2");
articleRepository.delete(articles);
}
/**
* 查询所有
*
* @author 孔垂云
*/
@Test
public void findAll() {
Iterable<Article> articles = articleRepository.findAll();
articles.forEach(article -> {
System.out.println(article.toString());
});
}
/**
* 根据author查询
*
* @author 孔垂云
*/
@Test
public void findByAuthor() {
List<Article> articles = articleRepository.findByAuthor("kcy");
articles.forEach(article -> {
System.out.println(article.toString());
});
}
/**
* 按照author和title查询
*
* @author 孔垂云
*/
@Test
public void findByAuthorAndTitle() {
List<Article> articles = articleRepository.findByAuthorAndTitle("kcy", "MongoTemplate的基本使用");
articles.forEach(article -> {
System.out.println(article.toString());
});
}
/**
* 根据作者查询,忽略大小写
*
* @author 孔垂云
*/
@Test
public void findByAuthorIgnoreCase() {
List<Article> articles = articleRepository.findByAuthorIgnoreCase("JASON");
articles.forEach(article -> {
System.out.println(article.getId());
});
}
/**
* 忽略所有参数的大小写
*
* @author 孔垂云
*/
@Test
public void findByAuthorAndTitleAllIgnoreCase() {
List<Article> articles = articleRepository.findByAuthorAndTitleAllIgnoreCase("KCY", "MONGOTEMPLATE的基本使用");
articles.forEach(article -> {
System.out.println(article.toString());
});
}
/**
* 根据author查询,并且以访问次数降序排序显示
*
* @author 孔垂云
*/
@Test
public void findByAuthorOrderByVisitCountDesc() {
List<Article> articles = articleRepository.findByAuthorOrderByVisitCountDesc("kcy");
articles.forEach(article -> {
System.out.println(article.toString());
});
}
/**
* 根据作者查询,并且以访问次数升序排序显示
*
* @author 孔垂云
*/
@Test
public void findByAuthorOrderByVisitCountAsc() {
List<Article> articles = articleRepository.findByAuthorOrderByVisitCountAsc("kcy");
articles.forEach(article -> {
System.out.println(article.toString());
});
}
/**
* 自带排序条件
*
* @author 孔垂云
*/
@Test
public void findByAuthorBySort() {
List<Article> articles = articleRepository.findByAuthor("kcy", new Sort(Direction.ASC, "VisitCount"));
articles.forEach(article -> {
System.out.println(article.toString());
});
}
/**
* 分页查询所有,并且排序
*/
@Test
public void findByPage() {
int page = 1;
int size = 2;
Pageable pageable = new PageRequest(page, size, new Sort(Direction.ASC, "VisitCount"));
Page<Article> pageInfo = articleRepository.findAll(pageable);
//总数量
System.out.println(pageInfo.getTotalElements());
//总页数
System.out.println(pageInfo.getTotalPages());
for (Article article : pageInfo.getContent()) {
System.out.println(article.toString());
}
}
}
上面一段代码较长,基本上MongoDB常用的各种例子都讲清楚了,比如增加、批量增加、修改、删除、按id查找、按标题查询、分页等等。
网友评论