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：

<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：

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);}}}

 

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);}}

 

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);}}

 

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;}}

 

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：