java操作MongoDB数据库

1：安装mongodb

（1）：下载mongodb，解压，在安装目录中创建data目录（与bin目录同级），在data目录下创建db目录

（2）：启动mongodb。进入cmd命令行工具，进入mongodb安装目录下的bin目录，输入命令 mongod -dbpath '{HOME}/data/db'

（3）：打开浏览器，输入：http://localhost:27017,显示：It looks like you are trying to access MongoDB over HTTP on the native driver port.说明启动成功。

2：使用eclipse创建一个maven项目开操作mongodb数据库。pom.xml文件如下：

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<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/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>

<groupId>com.chu</groupId>

<artifactId>mongotest</artifactId>

<packaging>war</packaging>

<version>0.0.1-SNAPSHOT</version>

<name>mongotest Maven Webapp</name>

<url>http://maven.apache.org</url>

<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>2.10.1</version>

</dependency>

<dependency>

<groupId>org.codehaus.jackson</groupId>

<artifactId>jackson-core-asl</artifactId>

<version>1.9.9</version>

</dependency>

<dependency>

<groupId>org.codehaus.jackson</groupId>

<artifactId>jackson-mapper-asl</artifactId>

<version>1.9.9</version>

</dependency>

</dependencies>

<build>

<finalName>mongotest</finalName>

</build>

</project>

Java代码如下：

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package com.mongo.action;

import java.net.UnknownHostException;

import java.util.List;

import com.mongo.po.User;

import com.mongo.service.UserService;

public class UserAction {

private UserService userService = new UserService();

public void save() throws UnknownHostException{

User user = new User();

user.setId(1);

user.setName("jinhui");

user.setAddress("beijing");

this.userService.save(user);

}

public void update()throws UnknownHostException{

User user = new User();

user.setId(1);

user.setName("manman");

user.setAddress("hebei");

this.userService.update(user);

}

public List<User> findAll()throws UnknownHostException{

return this.userService.findAll();

}

public void remove()throws UnknownHostException{

this.userService.remove(1);

}

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

UserAction userAction = new UserAction();

userAction.save();

// userAction.update();

// userAction.remove();

List<User> list = userAction.findAll();

for(User user : list){

System.out.println(user);

}

}

}

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package com.mongo.service;

import java.net.UnknownHostException;

import java.util.List;

import com.mongo.dao.UserDao;

import com.mongo.po.User;

public class UserService {

private UserDao userDao = new UserDao();

/**

* 保存

* @param user

* @throws UnknownHostException

*/

public void save(User user) throws UnknownHostException{

this.userDao.save(user);

}

/**

* 更新

* @param user

* @throws UnknownHostException

*/

public void update(User user) throws UnknownHostException {

this.userDao.update(user);

}

/**

* 查询所有

* @return

* @throws UnknownHostException

*/

public List<User> findAll() throws UnknownHostException{

return this.userDao.findAll();

}

/**

* 删除操作

* @param id

* @throws UnknownHostException

*/

public void remove(int id) throws UnknownHostException{

this.userDao.remove(id);

}

}

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package com.mongo.dao;

import java.net.UnknownHostException;

import java.util.ArrayList;

import java.util.List;

import com.mongo.po.User;

import com.mongodb.BasicDBObject;

import com.mongodb.DB;

import com.mongodb.DBCollection;

import com.mongodb.DBCursor;

import com.mongodb.DBObject;

import com.mongodb.Mongo;

import com.mongodb.util.JSON;

public class UserDao {

/**

* 保存

* @param user

* @throws UnknownHostException

*/

public void save(User user) throws UnknownHostException {

Mongo mongo = new Mongo();

DB myMongo = mongo.getDB("myMongo");

DBCollection userCollection = myMongo.getCollection("user");

DBObject dbo = (DBObject) JSON.parse(user.toJson());

userCollection.insert(dbo);

}

/**

* 更新

* @param user

* @throws UnknownHostException

*/

public void update(User user) throws UnknownHostException {

Mongo mongo = new Mongo();

DB myMongo = mongo.getDB("myMongo");

DBCollection userCollection = myMongo.getCollection("user");

BasicDBObject baseDBO = new BasicDBObject();

baseDBO.put("id", user.getId());

DBObject newDBO = (DBObject) JSON.parse(user.toJson());

userCollection.update(baseDBO, newDBO);

}

/**

* 查询所有

* @return

* @throws UnknownHostException

*/

public List<User> findAll() throws UnknownHostException{

Mongo mongo = new Mongo();

DB myMongo = mongo.getDB("myMongo");

DBCollection userCollection = myMongo.getCollection("user");

DBCursor cursor=userCollection.find();

List<User> userList = new ArrayList<User>();

while(cursor.hasNext()){

User user = new User();

user.parse(cursor.next());

userList.add(user);

}

return userList;

}

/**

* 删除操作

* @param id

* @throws UnknownHostException

*/

public void remove(int id) throws UnknownHostException{

Mongo mongo = new Mongo();

DB myMongo = mongo.getDB("myMongo");

DBCollection userCollection = myMongo.getCollection("user");

BasicDBObject baseDBO =new BasicDBObject();

baseDBO.put("id", id);

//删除某一条记录

userCollection.remove(baseDBO);

}

}

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package com.mongo.po;

import com.mongo.utils.JsonUtils;

import com.mongodb.DBObject;

public class User {

private int id;

private String name;

private String address;

public int getId() {

return id;

}

public void setId(int id) {

this.id = id;

}

public String getName() {

return name;

}

public void setName(String name) {

this.name = name;

}

public String getAddress() {

return address;

}

public void setAddress(String address) {

this.address = address;

}

public String toJson(){

return JsonUtils.toJson(this);

}

public void parse(DBObject dbo){

this.setId((Integer)dbo.get("id"));

this.setName((String)dbo.get("name"));

this.setAddress((String)dbo.get("address"));

}

public String toString(){

return "id:"+id+",name:"+name+",address:"+address;

}

}

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package com.mongo.utils;

import java.io.OutputStream;

import org.codehaus.jackson.map.ObjectMapper;

import org.codehaus.jackson.type.TypeReference;

/**

* Json转化工具，可以实现java对象和json字符串之间的互相转化<br />

*

*/

public class JsonUtils {

static ObjectMapper objectMapper = new ObjectMapper();

/**

* java 对象转换为json 存入流中

*

* @param obj

* @param out

*/

public static String toJson(Object obj) {

String s = "";

try {

s = objectMapper.writeValueAsString(obj);

} catch (Exception e) {

e.printStackTrace();

}

return s;

}

/**

* java 对象转换为json 存入流中

*

* @param obj

* @param out

*/

public static void toJson(Object obj, OutputStream out) {

try {

objectMapper.writeValue(out, obj);

} catch (Exception e) {

e.printStackTrace();

}

}

/**

* json 转为java对象

*

* @param json

* @param obj

*/

@SuppressWarnings({ "rawtypes", "unchecked" })

public static void fromJson(String json, Object obj, Class valueType) {

try {

obj = objectMapper.readValue(json, valueType);

} catch (Exception e) {

e.printStackTrace();

}

}

/**

* json 转为java对象

* @param json

* @param obj

* @param valueTypeRef

*/

@SuppressWarnings("rawtypes")

public static void fromJson(String json, Object obj, TypeReference valueTypeRef) {

try {

obj = objectMapper.readValue(json, valueTypeRef);

} catch (Exception e) {

e.printStackTrace();

}

}

/**

* json 转为java对象

*

* @param json

* @param obj

*/

@SuppressWarnings({ "rawtypes", "unchecked" })

public static Object fromJson(String json, Class valueType) {

Object obj = null;

try {

obj = objectMapper.readValue(json, valueType);

} catch (Exception e) {

e.printStackTrace();

}

return obj;

}

/**

* json 转为java对象

*

* @param json

* @param obj

* @param valueTypeRef

*/

@SuppressWarnings({ "rawtypes", "hiding" })

public static <Object> Object fromJson(String json, TypeReference valueTypeRef) {

Object obj = null;

try {

obj = objectMapper.readValue(json, valueTypeRef);

} catch (Exception e) {

e.printStackTrace();

}

return obj;

}

}

3：使用客户端工具查看数据：