mongodb之java CRUD 简单操作

我下载的是 mongo-2.8.0.jar — Version 2.8.0

打开mongo shell -- 新建数据库test --( use test)

打开eclipse新建工程，把junit,mongo-2.8.0.jar导入。

新建测试类如下：

package com.db;

import java.net.UnknownHostException;

import java.util.ArrayList;

import java.util.List;

import org.bson.types.ObjectId;

import org.junit.After;

import org.junit.Test;

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.MongoException;

public class DBUtils {

private static Mongo mongo;

private static DB db;

static {

try {

mongo = new Mongo("localhost", 27017);

} catch (UnknownHostException e) {

e.printStackTrace();

} catch (MongoException e) {

e.printStackTrace();

}

db = mongo.getDB("test");

}

@After

public void output() {

// 测试完显示所有

DBCollection dbc = db.getCollection("user");

DBCursor cursor = dbc.find();

while (cursor.hasNext()) {

// cursor.next就是一行记录(一个文档)

System.out.println(cursor.next());

}

}

@Test

public void testInsert() throws Exception {

DBCollection dbc = db.getCollection("user");

DBObject object = new BasicDBObject();

object.put("username", "zdw");

object.put("password", "123");

// 一个人有一个职位

// 数据库json格式：{username:"zdw",password:"123",position:{name:"工程师"}}

BasicDBObject o = new BasicDBObject();

o.put("name", "经理");

object.put("position", o);

dbc.insert(object);

object = new BasicDBObject();

object.put("username", "zhangjun");

object.put("password", "456");

// 一个人有多个职位(一个文档里有多个文档)

// 数据库json格式：{username:"zhangjun",password:"456",position:[{name:"工程师"},{name:"设计师"}]}

List<Object> list = new ArrayList<Object>();

o = new BasicDBObject();

o.put("name", "工程师");

list.add(o);

o = new BasicDBObject();

o.put("name", "设计师");

list.add(o);

object.put("position", list);

dbc.insert(object);

}

// 删除指定

@Test

public void testRemoveOne() throws Exception {

DBCollection dbc = db.getCollection("user");

DBObject o = new BasicDBObject();

o.put("username", "zhangjun");

dbc.remove(o);

}

@Test

public void testModify() throws Exception {

DBCollection dbc = db.getCollection("user");

// 根据id修改密码,需要加$set,否则所有记录的password都会被修改，其它字段删除。

int result = dbc.update(

new BasicDBObject("_id", new ObjectId(

"4ff8eaa65dbc67340278a07c")),

new BasicDBObject("$set", new BasicDBObject("password",

"4444"))).getN();

System.out.println(result);

}

@Testhttp://www.shengshiyouxi.com

public void testRemove() throws Exception {

DBCollection dbc = db.getCollection("user");

// 删除全部

dbc.drop();

}

// 查询指定

@Test

public void testFindOne() throws Exception {

DBCollection dbc = db.getCollection("user");

DBObject o = new BasicDBObject();

o.put("username", "zdw");

DBObject obj = dbc.findOne(o);

System.out.println(obj);

}

}

这种key-value存储方式，操作很方便。

源码下载