【MongoDb學習之路】Java利用MongoClient類連線MongoDB資料庫
專案需要 mongo-java-driver-3.0.2 .jar
【重點看加粗字型,方法體中註釋的都是系統連線引數】
package cn.com.mongodb;
import com.mongodb.DB;
import com.mongodb.DBCollection;
import com.mongodb.DBCursor;
import com.mongodb.MongoClient;
/**
* JAVA連結mongodb資料庫
*
* @author Admin Song
*
*/
public class ConnMongoDB {
/**
* 連結的ip
*/
private static final String HOST = "localhost";
/**
* 埠
*/
private static final int PORT = 27017;
/**
* 使用者名稱
*/
private static final String USER_NAME = "";
/**
* 密碼
*/
private static final String PASSWORD = "";
/**
* 資料庫名
*/
private static final String DATA_BASENAME= "Test";
/**
* 表名
*/
private static final String TABLE_NAME= "song";
/**
* 查詢一個表中所有的內容
* @throws Exception
*/
public void mongoDB() throws Exception {
//mongoClient 連線伺服器端 Dubeg引數:
//Mongo{options=MongoClientOptions{description='null', readPreference=primary, writeConcern=WriteConcern{w=1, wtimeout=0, fsync=false, j=false, cod
MongoClient mongoClient = new MongoClient(HOST, PORT);
//db 連線資料庫 Dubeg引數:
//DB{name='Test'}
DB db = mongoClient.getDB(DATA_BASENAME);
//dbCollection 連線表 Dubeg引數:
//DBCollection{database=DB{name='Test'}, name='song'}
DBCollection dbCollection = db.getCollection(TABLE_NAME);
//dbCursor 查詢當前表的所有資料 Dubeg引數:
//DBCursor{collection=DBCollection{database=DB{name='Test'}, name='song'}, find=FindOptions{, batchSize=0, limit=0, modifiers=null, projection=null, maxTimeMS=0, skip=0, sort=null, cursorType=NonTailable, noCursorTimeout=false, oplogReplay=false, partial=false}}
DBCursor dbCursor = dbCollection.find();
//迭代器檢測dbCursor序列中是否還有下一個元素
while (dbCursor.hasNext()) {
//如果有就讀取
System.out.println(dbCursor.next());
}
}
public static void main(String[] args) {
try {
new ConnMongoDB().mongoDB();
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
//main方法執行過後就會在控制檯打印出連線表當前的所有資料
============================================================
{ "_id" : { "$oid" : "5a2ab075d7feb6ad442d9adf"} , "id" : 1.0 , "name" : "name1" , "sex" : null }
{ "_id" : { "$oid" : "5a2ab07bd7feb6ad442d9ae0"} , "id" : 2.0 , "name" : "name2" , "sex" : null }
{ "_id" : { "$oid" : "5a2ab080d7feb6ad442d9ae1"} , "id" : 3.0 , "name" : "name3"}
{ "_id" : { "$oid" : "5a2ab085d7feb6ad442d9ae2"} , "id" : 4.0 , "name" : "name4"}
{ "_id" : { "$oid" : "5a2ab08bd7feb6ad442d9ae3"} , "id" : 5.0 , "name" : "name5"}
{ "_id" : { "$oid" : "5a2ab090d7feb6ad442d9ae4"} , "id" : 6.0 , "name" : "name6"}
{ "_id" : { "$oid" : "5a2ac0eed7feb6ad442d9ae5"} , "id" : 7.0 , "list" : [ "aaa" , "bbb" , "ccc" , "ddd"]}
{ "_id" : { "$oid" : "5a2ac10ed7feb6ad442d9ae6"} , "id" : 8.0 , "list" : [ 111.0 , 222.0 , 333.0 , 444.0]}
{ "_id" : { "$oid" : "5a2ac2b1d7feb6ad442d9ae7"} , "id" : 9.0 , "list" : [ 1.0 , 2.0 , 3.0]}
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