如何将数据库作为参数连接到 mysql 数据库服务器

how to take database as parameter to connect to mysql database server

import java.sql.*;
class ConnectSql
{
    static Connection cont(String db)throws Exception
    {
        Class.forName("com.mysql.jdbc.Driver");
        Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306/"+db+","root","xyz" );  
        return(con);
    }
}

我在编译此函数时遇到问题,第 7 行我想语法有问题 error.If 所以请告诉 me.Here 我想将数据库名称作为参数从调用中收到 function.When 我给出了数据库的确切名称而不是它工作的参数,但是在我在连接线中传递参数之后没有。

应该是

Connection con=DriverManager.getConnection("jdbc:mysql://localhost:3306/"+db,"root","xyz" );

问题是

"+db+"

你有额外的"标记

Connection con=null;

String DB_URL = "jdbc:mysql://localhost:3306/";
String USER = "abc";//db user name
String PASS = "abc";//db password     


public synchronized Connection getConnection(String dbname)
{
 try
    {
      Class.forName("com.mysql.jdbc.Driver");//loading mysql driver 
      con = DriverManager.getConnection(DB_URL+dbname,USER,PASS);//connecting to mysql
    }
    catch(Exception e)
    {
        e.printStackTrace();
    }
    return con;
}