package com.infomorrow.webroot; import java.util.List; 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 test_mongodb { public static void main(String args[]) throws Exception { MongoClient mongoClient = new MongoClient( "127.0.0.1" , 27017 );//建立连接 DB get_db_credit = mongoClient.getDB("credit_2");//数据库名 DBCollection collection = get_db_credit.getCollection("report");//集合名,对应mysql中的表名 BasicDBObject filter_dbobject = new BasicDBObject(); //建立查询条件,如果还有其他条件,类似的写即可 // 如:version=3,filter_dbobject.put("version", 3),mongod区分String 和 Integer类型,所以要小心"3"!=3 filter_dbobject.put("user_id", "10065716153075"); //下面执行查询,设置limit,只要10条数据,排序(类mysql orderby) 再建一个BasicDBObject即可,-1表示倒序 DBCursor cursor = collection.find(filter_dbobject).limit(10).sort(new BasicDBObject("create_time",-1)); //把结果集输出成list类型 List<DBObject> list = cursor.toArray(); System.out.println(list.size());//list的长度 System.err.println(cursor.count());//计算结果的数量,类似于(mysql count()函数),不受limit的影响 //遍历结果集 while(cursor.hasNext()) { System.out.println(cursor.next()); } } }
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