mongodb之java CRUD 简单操作

驱动包下载：https://github.com/mongodb/mongo-java-driver/downloads
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);    }    @Test    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