MongoDB学习(二)MongoDB Java增删查改(2)

package com.archie.mongodb;

import com.mongodb.BasicDBObject;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.DBObject;

/**

* 对指定DBCollection集合的CRUD操作
* @author archie2010
*
* since 2012-9-29 下午10:51:24
*/
public class CRUDTest {
  /**
* 增加
* @param obj
*/
  public static void add(DBObject obj){
  DBCollection coll=DBUtil.getDBCollection("dbtest", "emp");
  coll.insert(obj);
  }
  /**
* 删除
* @param obj
*/
  public static void delete(DBObject obj){
  DBCollection coll=DBUtil.getDBCollection("dbtest", "emp");
  coll.remove(obj);
  }
  /**
* 查询
*/
  public static void query(){
  DBCollection coll=DBUtil.getDBCollection("dbtest", "emp");
  // 查询集合中所有的数据
  DBCursor cur = coll.find();
  System.out.println("Record Count:" + cur.count());
  while (cur.hasNext()) {
  DBObject object = cur.next();
  System.out.println(object);
  // 取出对象中列表为'uname'和'upwd'的数据
  System.out.println("uname:" + object.get("uname") + "\tupwd:"
  + object.get("upwd")+"\t_id:"+object.get("_id"));
  }
  }
  /**
* 修改
*/
  public static void modify(DBObject orig,DBObject update){
  DBCollection coll=DBUtil.getDBCollection("dbtest", "emp");
  coll.update(orig, update, true, false);
  }
  public static void main(String[] args) {
  DBObject empObj=new BasicDBObject();
  empObj.put("uname", "teddy");
  empObj.put("upwd", "123456");
  //添加
  add(empObj);
  query();
 

  DBObject updateObj=new BasicDBObject();
  updateObj.put("uname", "teddy");
  updateObj.put("upwd", "3333");
  //更新
  modify(new BasicDBObject("uname","teddy"),updateObj);
  System.out.println("-----------------------修改后-------------------");