在链接前，需要启动mongoDB服务端，并在java项目中导入fastjson和mongo-java-driver包
package com.mwc.test; import java.net.UnknownHostException; import java.util.ArrayList; import java.util.List; import com.alibaba.fastjson.JSON; import com.mongodb.BasicDBObject; import com.mongodb.DB; import com.mongodb.DBCollection; import com.mongodb.DBCursor; import com.mongodb.DBObject; import com.mongodb.MongoClient; public class Mongoooo { public static DBCollection utill(String dbname,String colname) { try { //获得链接对象 MongoClient mongoClient=new MongoClient("127.0.0.1",27017); //获得数据库对象 DB db=mongoClient.getDB(dbname); //获取集合名 DBCollection dbCollection=db.getCollection(colname); return dbCollection; } catch (UnknownHostException e) { e.printStackTrace(); return null; } } /** * 查询集合 * @param collname 集合名 */ public void selectt(String collname) { DBCollection db1=utill("qly", collname); DBObject dbObject=new BasicDBObject(); DBCursor dbCursor=db1.find(); List<User> ll=new ArrayList<User>(); for(DBObject dbObject2:dbCursor) { //转化为json串 String ss=JSON.toJSONString(dbObject2); //转化为user对象 User user=JSON.parseObject(ss,User.class); ll.add(user); System.out.println(user); } } /** * 添加 * @param collname 集合名 * @param dbObject 数据 * @return */ public void insertt(String collname,DBObject dbObject) { DBCollection db2=utill("qly", collname); db2.insert(dbObject); System.out.println("添加成功！"); } /** * 修改 * @param collname 集合名 * @param dbObject1 条件 * @param dbObject2 修改的数据 */ public void updatee(String collname,DBObject dbObject1,DBObject dbObject2) { DBCollection db3=utill("qly", collname); db3.update(dbObject1, dbObject2, false, true); System.out.println("修改成功！"); } /** * 删除 * @param collname 集合名 * @param dbObject 条件 */ public void deletee(String collname,DBObject dbObject) { DBCollection db4=utill("qly", collname); db4.remove(dbObject); System.out.println("修改成功!"); } public static void main(String[] args) { DBObject dbb1=new BasicDBObject(); DBObject dbb2=new BasicDBObject(); Mongoooo mongoooo=new Mongoooo(); //查询user集合 mongoooo.selectt("user"); //添加数据到user集合中 dbb1.put("name", "qly"); dbb1.put("age", 22); mongoooo.insertt("user", dbb1); //删除一条数据 dbb2.put("name", "qly1"); mongoooo.deletee("user", dbb2); //修改一条数据 DBObject dbb4=new BasicDBObject(); DBObject dbb5=new BasicDBObject(); dbb4.put("name", "qly"); DBObject dbb3=new BasicDBObject(); dbb3.put("age", 10); dbb5.put("$set", dbb3); mongoooo.updatee("user", dbb4, dbb5); } }
