簡單的spring-data集成mongoDB項目,實現crud的功能

時間 2019-11-09

標籤簡單 spring data 集成 mongodb 項目實現 crud 功能欄目 Spring 简体版

原文原文鏈接

集成了spring框架的jar,加上三個spring-data的jar和一個驅動包java

用IDE開發工具新建一個java 項目，須要spring框架的包，和spring-data須要的包，分別是spring

包下的三個包：spring-data-mongodbmongodb

,spring-data-mongodb-cross-store,spring-data-mongodb-log4j。數據庫

以及mongoDB數據庫的驅動包mongo-2.8.0.jar,也須要commons-logging-1.0.4和log4j-1.2.17.jar包，若是還缺乏什麼包，更加報錯添加便可express

項目須要的目錄結構：app

每一個類中完整的代碼貼出以下：框架

實體類：ide

這裏也解釋一下代碼註解函數

工具

spring-data-mongodb中的實體映射是經過

MongoMappingConverter這個類實現的。它能夠經過註釋把

java類轉換爲mongodb的文檔。
它有如下幾種註釋：
@Id - 文檔的惟一標識，在mongodb中爲ObjectId，它是惟一的，經過時間戳+機器標識+進程ID+自增計數器（確保同一秒內產生的Id不會衝突）構成。

@Document - 把一個java類聲明爲mongodb的文檔，能夠通

過collection參數指定這個類對應的文檔。

@DBRef - 聲明相似於關係數據庫的關聯關係。

@Indexed - 聲明該字段須要索引，建索引能夠大大的提升查詢效率。

@CompoundIndex - 複合索引的聲明，建複合索引能夠有效地提升多字段的查詢效率。

@GeoSpatialIndexed - 聲明該字段爲地理信息的索引。

@Transient - 映射忽略的字段，該字段不會保存到

mongodb。

@PersistenceConstructor - 聲明構造函數，做用是把從數據庫取出的數據實例化爲對象。該構造函數傳入的值爲從DBObject中取出的數據。

package main.pojo;

import org.springframework.data.annotation.Id;
import org.springframework.data.mongodb.core.mapping.Document;

@Document
public class Tree {
@Id
private String id;
private String name;
private String category;
private int age;
public Tree(String id, String name, int age) {
this.id = id;
this.name = name;
this.age = age;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getCategory() {
return category;
}
public void setCategory(String category) {
this.category = category;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public String toString() {
return "Person [id=" + id + ", name=" + name + ", age=" + age
+ ", category=" + category + "]";
}
}

鏈接mongodb的dao層

package main.dao;

import com.mongodb.WriteResult;

import java.util.List;

public interface Repository<T> {
//方法接口
public List<T> getAllObjects();

public void saveObject(T object);

public T getObject(String id);

public WriteResult updateObject(String id, String name);

public void deleteObject(String id);

public void createCollection();

public void dropCollection();

}

實現類：

package main.impl;

import com.mongodb.WriteResult;
import main.dao.Repository;
import main.pojo.Tree;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.data.mongodb.core.query.Update;

import java.util.List;

public class RepositoryImpl implements Repository<Tree>{
MongoTemplate mongoTemplate;

// Repository repository;
//
// public void setRepository(Repository repository) {
// this.repository = repository;
// }

public void setMongoTemplate(MongoTemplate mongoTemplate) {
this.mongoTemplate = mongoTemplate;
}

//查詢
public List<Tree> getAllObjects() {
return mongoTemplate.findAll(Tree.class);
}

//增長
public void saveObject(Tree tree) {
mongoTemplate.insert(tree);
}

//查詢
public Tree getObject(String id) {
return mongoTemplate.findOne(new Query(Criteria.where("id").is(id)), Tree.class);
}

//修改
public WriteResult updateObject(String id, String name) {
return mongoTemplate.updateFirst(
new Query(Criteria.where("id").is(id)),
Update.update("name", name), Tree.class);
}

//刪除
public void deleteObject(String id) {
mongoTemplate .remove(new Query(Criteria.where("id").is(id)), Tree.class);
}

public void createCollection() {
if (!mongoTemplate.collectionExists(Tree.class)) {
mongoTemplate.createCollection(Tree.class);
}
}

public void dropCollection() {
if (mongoTemplate.collectionExists(Tree.class)) {
mongoTemplate.dropCollection(Tree.class);
}
}

}

applicationContext.xml的配置信息

<?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"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.1.xsd

http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context-3.1.xsd">

<bean id="Repository"
class="main.impl.RepositoryImpl">
<property name="mongoTemplate" ref="mongoTemplate" />
</bean>

<bean id="mongoTemplate" class="org.springframework.data.mongodb.core.MongoTemplate">
<constructor-arg name="mongo" ref="mongo" />
<constructor-arg name="databaseName" value="temp" />
</bean>

<bean id="mongo" class="org.springframework.data.mongodb.core.MongoFactoryBean">
<property name="host" value="localhost" />
<property name="port" value="27017" />
</bean>

<context:annotation-config />

<context:component-scan base-package="main">

<context:exclude-filter type="annotation"
expression="org.springframework.context.annotation.Configuration" />

</context:component-scan>

</beans>

最後是crud的測試類

package main.test;

import main.dao.Repository;
import main.impl.RepositoryImpl;
import main.pojo.Tree;
import org.springframework.context.ConfigurableApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class MongoTest {
public static void main(String[] args) {
System.out.println("進來了");
ConfigurableApplicationContext context = new ClassPathXmlApplicationContext(
"classpath:/main/applicationContext.xml");
Repository repository = context.getBean(RepositoryImpl.class);
// cleanup collection before insertion
repository.dropCollection();
// create collection
repository.createCollection();
//增長
repository.saveObject(new Tree("1", "Apple Tree", 10));
System.out.println("1. " + repository.getAllObjects());

//增長和查詢
repository.saveObject(new Tree("2", "Orange Tree", 3));
System.out.println("2. " + repository.getAllObjects());
System.out.println("Tree with id 1" + repository.getObject("1"));

//修改
repository.updateObject("1", "Peach Tree");
System.out.println("3. " + repository.getAllObjects());

//刪除
repository.deleteObject("2");
System.out.println("4. " + repository.getAllObjects());
}

}