java jdbc_connection连接数据库代码

package org.marker.test;

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

public class JdbcConnection {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		 try
		    {
		      String url="jdbc:mysql://localhost:3306/iotp";
		      String user="root";
		      String pwd="1q2w";
		      
		      //加载驱动，这一句也可写为：Class.forName("com.mysql.jdbc.Driver");
		     Class.forName("com.mysql.jdbc.Driver").newInstance();
		      //建立到MySQL的连接
		       Connection conn = DriverManager.getConnection(url,user, pwd);
		      
		      //执行SQL语句
		       Statement stmt = conn.createStatement();//创建语句对象，用以执行sql语言
		      ResultSet rs = stmt.executeQuery("select * from t_comm_user");
		     
		       //处理结果集
		      while (rs.next())
		      {
		        String name = rs.getString("USER_NAME_CN");
		        System.out.println(name);
		      }
		      rs.close();//关闭数据库
		      conn.close();
		    }
		    catch (Exception ex)
		    {
		      System.out.println("Error : " + ex.toString());
		    }

	}

}