jdbc 规范 基础

JDBC规范  

package test.jdbc;

import java.sql.DriverManager;
import java.sql.ResultSet;

import java.sql.Connection;
import java.sql.Statement;
public class Base
{
 public static void main(String[] args) throws Exception
 {
  template();
 }
 static void template() throws Exception
 {
  String url="jdbc:mysql://localhost:3306/jdbc";
  String user="root";
  String password="123";
  Connection conn=null;
  Statement st=null;
  ResultSet rs=null;
  try
  {
   //1.注册驱动
   Class.forName("com.mysql.jdbc.Driver");
   //2.建立连接
   conn=DriverManager.getConnection(url,user,password);
   //3.创建语句
   st=conn.createStatement();
   //4.执行语句
   rs=st.executeQuery("select * from user");
   //5.处理结果
   while (rs.next())
   {
    System.out.println(rs.getObject(1)+"\t"+rs.getObject(2)+"\t"+rs.getObject(3)+"\t"+rs.getObject(4));
   }
  } finally
  {
   try
   {
    if (rs!=null)
     rs.close();
   } finally
   {
    try
    {
     if(st!=null)
      st.close();
    } finally
    {
     if(conn!=null)
      conn.close();
    }
   }
   
   
  }
 }
}