mongodb 笔记

1.java驱动下的mongo操作

　　1.1 数据库连接

　　

 package com.mongodb.text;

 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));
     }
 }

DataBase

1.2 数据库常见操作

 package com.mongodb.text;

 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("$set",
 //                new BasicDBObject("eamil","uspcat@126.com"));
 //        mongoDb.update(new BasicDBObject(),
 //                update,false,true,"javadb");
         /**
          * 7.查询出persons集合中的name和age
          */
 //        DBObject keys = new BasicDBObject();
 //        keys.put("_id", false);
 //        keys.put("name", true);
 //        keys.put("age", true);
 //        DBCursor cursor = mongoDb.find(null, keys, "persons");
 //        while (cursor.hasNext()) {
 //            DBObject object = cursor.next();
 //            System.out.println(object.get("name"));
 //        }
         /**
          * 8.查询出年龄大于26岁并且英语成绩小于80分
          */
 //        DBObject ref = new BasicDBObject();
 //        ref.put("age", new BasicDBObject("$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"));
 //        }
         /**
          * 9.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;
     }
 }

MongoDb