import java.sql.*;
public class Jdbc {
private static Connection Conn;
//这一句起了什么作用 为什么没有这句运行就错误
public static void main(String [] args){
String driverName="com.microsoft.sqlserver.jdbc.SQLServerDriver";
String dbURL="jdbc:sqlserver://localhost:1433;DatabaseName=mydate";
String userName="sa";
String userPwd="lzm0922";
try{
Class.forName(driverName);
Connection Conn=DriverManager.getConnection(dbURL,userName,userPwd);
System.out.println("连接数据库成功");
Statement stmt = Conn.createStatement();
ResultSet rs=stmt.executeQuery("SELECT * FROM BOOK");
while(rs.next()){
String Bno=rs.getString("Bno");
System.out.println(Bno);
System.out.println(rs.getString("Bname"));
}
rs.close();
stmt.close();
Conn.close();
}
catch(Exception e){
e.printStackTrace();
System.out.print("连接失败");
}
}
}
把这一句的private改为public也出现 错误 为什么呢 求前辈帮助、