java操作mongoDB数据库的简单实例

首先导入mongoDB的jar包http://pan.baidu.com/s/1bnGMJRD

//DataBase.java

package com.mongodb.test;

import java.net.UnknownHostException;

import com.mongodb.DB;

import com.mongodb.DBCollection;

import com.mongodb.DBCursor;

import com.mongodb.DBObject;

import com.mongodb.Mongo;

import com.mongodb.MongoException;

import com.mongodb.util.JSON;

public class DataBase {

public static void main(String[] args)

throws UnknownHostException, MongoException {

//1.建立一个Mongo的数据库连接对象

Mongo mg = new Mongo("127.0.0.1:27017");

//查询所有的Database

for (String name : mg.getDatabaseNames()) {

System.out.println("dbName: " + name);

}

//2.创建相关数据库的连接

DB db = mg.getDB("foobar");

//查询数据库所有的集合

for (String name : db.getCollectionNames()) {

System.out.println("collectionName: " + name);

}

DBCollection users = db.getCollection("persons");

//查询所有的数据

DBCursor cur = users.find();

while (cur.hasNext()) {

DBObject object = cur.next();

System.out.println(object.get("name"));

}

System.out.println(cur.count());

System.out.println(cur.getCursorId());

System.out.println(JSON.serialize(cur));

}

}

//MongoDb.java

package com.mongodb.test;

import java.net.UnknownHostException;

import java.util.List;

import org.bson.types.ObjectId;

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 MongoDb {

//1.建立一个Mongo的数据库连接对象

static Mongo connection = null;

//2.创建相关数据库的连接

static DB db = null;

public MongoDb(String dbName) throws UnknownHostException, MongoException{

connection = new Mongo("127.0.0.1:27017");

db = connection.getDB(dbName);

}

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

//实例化

MongoDb mongoDb = new MongoDb("foobar");

/**

* 1.创建一个名字叫javadb的数据库

*/

// mongoDb.createCollection("javadb");

/**

* 2.为集合javadb添加一条数据

*/

// DBObject dbs = new BasicDBObject();

// dbs.put("name", "uspcat.com");

// dbs.put("age", 2);

// List<String> books = new ArrayList<String>();

// books.add("EXTJS");

// books.add("MONGODB");

// dbs.put("books", books);

// mongoDb.insert(dbs, "javadb");

/**

* 3.批量插入数据

*/

// List<DBObject> dbObjects = new ArrayList<DBObject>();

// DBObject jim = new BasicDBObject("name","jim");

// DBObject lisi = new BasicDBObject("name","lisi");

// dbObjects.add(jim);

// dbObjects.add(lisi);

// mongoDb.insertBatch(dbObjects, "javadb");

/**

* 4.根据ID删除数据

*/

// mongoDb.deleteById("502870dab9c368bf5b151a04", "javadb");

/**

* 5.根据条件删除数据

*/

// DBObject lisi = new BasicDBObject();

// lisi.put("name", "lisi");

// int count = mongoDb.deleteByDbs(lisi, "javadb");

// System.out.println("删除数据的条数是: "+count);

/**

* 6.更新操作,为集合增加email属性

*/

// DBObject update = new BasicDBObject();

// update.put("$set",

// new BasicDBObject("eamil","test@126.com"));

// mongoDb.update(new BasicDBObject(),

// update,false,true,"javadb");

/**

* 7.查询出persons集合中的name和age

*/

// DBObject keys = new BasicDBObject();

// keys.put("_id", false);

// keys.put("name", true);

// keys.put("age", true);

// DBCursor cursor = mongoDb.find(null, keys, "persons");

// while (cursor.hasNext()) {

// DBObject object = cursor.next();

// System.out.println(object.get("name"));

// }

/**

* 7.查询出年龄大于26岁并且英语成绩小于80分

*/

// DBObject ref = new BasicDBObject();

// ref.put("age", new BasicDBObject("$gte",26));

// ref.put("e", new BasicDBObject("$lte",80));

// DBCursor cursor = mongoDb.find(ref, null, "persons");

// while (cursor.hasNext()) {

// DBObject object = cursor.next();

// System.out.print(object.get("name")+"-->");

// System.out.print(object.get("age")+"-->");

// System.out.println(object.get("e"));

// }

/**

* 8.分页例子

*/

DBCursor cursor = mongoDb.find(null, null, 0, 3, "persons");

while (cursor.hasNext()) {

DBObject object = cursor.next();

System.out.print(object.get("name")+"-->");

System.out.print(object.get("age")+"-->");

System.out.println(object.get("e"));

}

//关闭连接对象

connection.close();

}

/**

* 穿件一个数据库集合

* @param collName 集合名称

* @param db 数据库实例

*/

public void createCollection(String collName){

DBObject dbs = new BasicDBObject();

db.createCollection("javadb", dbs);

}

/**

* 为相应的集合添加数据

* @param dbs

* @param collName

*/

public void insert(DBObject dbs,String collName){

//1.得到集合

DBCollection coll = db.getCollection(collName);

//2.插入操作

coll.insert(dbs);

}

/**

* 为集合批量插入数据

* @param dbses

* @param collName

*/

public void insertBatch(List<DBObject> dbses,String collName){

//1.得到集合

DBCollection coll = db.getCollection(collName);

//2.插入操作

coll.insert(dbses);

}

/**

* 根据id删除数据

* @param id

* @param collName

* @return 返回影响的数据条数

*/

public int deleteById(String id,String collName){

//1.得到集合

DBCollection coll = db.getCollection(collName);

DBObject dbs = new BasicDBObject("_id", new ObjectId(id));

int count = coll.remove(dbs).getN();

return count;

}

/**

* 根据条件删除数据

* @param id

* @param collName

* @return 返回影响的数据条数

*/

public int deleteByDbs(DBObject dbs,String collName){

//1.得到集合

DBCollection coll = db.getCollection(collName);

int count = coll.remove(dbs).getN();

return count;

}

/**

* 更新数据

* @param find 查询器

* @param update 更新器

* @param upsert 更新或插入

* @param multi 是否批量更新

* @param collName 集合名称

* @return 返回影响的数据条数

*/

public int update(DBObject find,

DBObject update,

boolean upsert,

boolean multi,

String collName){

//1.得到集合

DBCollection coll = db.getCollection(collName);

int count = coll.update(find, update, upsert, multi).getN();

return count;

}

/**

* 查询器(分页)

* @param ref

* @param keys

* @param start

* @param limit

* @return

*/

public DBCursor find(DBObject ref,

DBObject keys,

int start,

int limit,

String collName){

DBCursor cur = find(ref, keys, collName);

return cur.limit(limit).skip(start);

}

/**

* 查询器(不分页)

* @param ref

* @param keys

* @param start

* @param limit

* @param collName

* @return

*/

public DBCursor find(DBObject ref,

DBObject keys,

String collName){

//1.得到集合

DBCollection coll = db.getCollection(collName);

DBCursor cur = coll.find(ref, keys);

return cur;

}

}