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;
}
}