JDBC入門 DbUtil

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;

public class DbUtil {

    public static final String URL = "jdbc:mysql://localhost:3306/rent?useUnicode=true&characterEncoding=utf-8&useSSL=false";
    public static final String USER = "root";
    public static final String PASSWORD = "mxy2525624";

    public static void main(String[] args) throws Exception {
        //1.加載驅動程序
        Class.forName("com.mysql.jdbc.Driver");
        //2. 獲得數據庫連接
        Connection conn = DriverManager.getConnection(URL, USER, PASSWORD);
        //3.操作數據庫，實現增刪改查
        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("SELECT “userName” FROM userinfo");
        //如果有數據，rs.next()返回true
        while(rs.next()){
            System.out.println(rs.getString("“userName”")+" 年齡：");
        }
    }
}