<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[qq_38049721的博客]]></title><description><![CDATA[总结一天所学的知识]]></description><link>https://blog.youkuaiyun.com/qq_38049721</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; qq_38049721]]></copyright><item><title><![CDATA[java代码操作redis：]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/74509487</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/74509487</guid><author>qq_38049721</author><pubDate>Wed, 05 Jul 2017 23:44:59 +0800</pubDate><description><![CDATA[public class Demo{
 
      @Test
   public void t2(){
      //创建连接池的配置对象
      JedisPoolConfig config = newJedisPoolConfig();
      //配置连接池的初始化连接数
      config.setMaxTotal(100);
      //配置空闲时期]]></description><category></category></item><item><title><![CDATA[servlet中的三大作用域]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/74278896</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/74278896</guid><author>qq_38049721</author><pubDate>Mon, 03 Jul 2017 23:44:13 +0800</pubDate><description><![CDATA[servletContext:
创建: 服务器启动,服务器为项目创建对应的servletContext对象 只有一个
销毁: 服务器正常关闭或则项目移除
作用域: 整个项目下的所有servlet都可以共享(公共的)


request:
创建: 浏览器访问服务器sevlet的时候创建  访问一个创建一个
销毁: 服务器响应回来,该request对象销毁
作用域: 一次请求.多个转]]></description><category></category></item><item><title><![CDATA[使用ajax判断数据库是否存在已有用户名]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/74014381</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/74014381</guid><author>qq_38049721</author><pubDate>Fri, 30 Jun 2017 22:38:44 +0800</pubDate><description><![CDATA[在index.jsp输入：
案例一的实现
   校验用户名a>
 
在demo1输入：

    pageEncoding="UTF-8"%>




Inserttitle here


   $(function(){
      $("#username").blur(function(){
         if($.trim($("#username").]]></description><category></category></item><item><title><![CDATA[删除数据库的商品]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/73865437</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/73865437</guid><author>qq_38049721</author><pubDate>Thu, 29 Jun 2017 00:00:25 +0800</pubDate><description><![CDATA[删除的时候，要开启事务
 
在service层中开启事务：
public voiddelAll(String[] pids) {
      Connection con = null;
      try {
         DaoDemo dd = new DaoDemo();
         //先获取开启事务
         con = JDBCUtils.getCo]]></description><category></category></item><item><title><![CDATA[用Listener监听器：发送生日祝福邮件]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/73730812</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/73730812</guid><author>qq_38049721</author><pubDate>Sun, 25 Jun 2017 23:52:01 +0800</pubDate><description><![CDATA[package cn.itcast.listener;

public class DemoListener implements ServletContextListener{


@Override
public void contextInitialized(ServletContextEvent arg0) {
System.out.println("服务器启动了...");]]></description><category></category></item><item><title><![CDATA[用jsp展示数据库的商品：]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/73612243</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/73612243</guid><author>qq_38049721</author><pubDate>Thu, 22 Jun 2017 23:56:04 +0800</pubDate><description><![CDATA[创建ListServlet层：


package cn.itcast.web;


public class ListServlet extends HttpServlet {
private static final long serialVersionUID = 1L;


protected void doGet(HttpServletRequest request, ]]></description><category></category></item><item><title><![CDATA[显示用户上次访问的事件]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/73522531</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/73522531</guid><author>qq_38049721</author><pubDate>Tue, 20 Jun 2017 23:58:33 +0800</pubDate><description><![CDATA[package cn.itcast.cookie;


import java.io.IOException;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.Date;


import javax.servlet.ServletException;
import]]></description><category></category></item><item><title><![CDATA[Servlet中  请求转发：]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/73442460</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/73442460</guid><author>qq_38049721</author><pubDate>Sun, 18 Jun 2017 23:57:25 +0800</pubDate><description><![CDATA[请求转发和重定向的区别:
重定向最少两次请求两次响应,转发只有一次请求一次响应
重定向地址栏发生变化,转发地址栏不变
重定向是响应对象(response)的方法,请求转发是请求对象(request)的方法




在index.HTML中输入：
请求转发


在web.xml中输入：

    
    ServletDemo05
    ServletDemo05]]></description><category></category></item><item><title><![CDATA[servlet---response方法]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/73359799</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/73359799</guid><author>qq_38049721</author><pubDate>Sat, 17 Jun 2017 00:12:51 +0800</pubDate><description><![CDATA[统计一个servlet的访问次数
需求:
有一个servlet(countServlet),每访问一次这个servlet,将访问的次数+1,
当我们访问另一个servlet(showServlet),展示访问CountServlet的次数


需要创建2个sevlet(countServlet--计数  showServlet--获取显示)




package cn.it]]></description><category></category></item><item><title><![CDATA[validate的使用]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/73264746</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/73264746</guid><author>qq_38049721</author><pubDate>Thu, 15 Jun 2017 00:04:26 +0800</pubDate><description><![CDATA[validate是jQuery插件，必须在jQuery的基础上进行运行, 使用之前需要导入jQuery库、validate库、和国际化资源库


校验方式：
语法：$(…).validate({
rules:{},
messages:{}
})













/*页面加载成功后选中要校验的表单对象
*/
$(function(){
//选]]></description><category></category></item><item><title><![CDATA[左右选中.html]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/73150347</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/73150347</guid><author>qq_38049721</author><pubDate>Tue, 13 Jun 2017 00:18:37 +0800</pubDate><description><![CDATA[左右选中.html


input[type='button'] {
width: 50px;
}



$(function(){
//将左边选中的第一个插入到右边的下拉选中
$("#toRight1").click(function(){
$("#left option:selected:first").appendTo("#right");
});
//将左边选中]]></description><category></category></item><item><title><![CDATA[html，省市联动]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/72973118</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/72973118</guid><author>qq_38049721</author><pubDate>Sat, 10 Jun 2017 00:21:53 +0800</pubDate><description><![CDATA[// 定义二维数组:
var arr = new Array(4);
arr[0] = new Array("石家庄","邯郸","保定","秦皇岛");
arr[1] = new Array("郑州市","洛阳市","安阳市","南阳市");
arr[2] = new Array("沈阳市","锦州市","大连市","铁岭市");
arr[3] = new Array("长春市","吉]]></description><category></category></item><item><title><![CDATA[注册页面校验]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/72905650</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/72905650</guid><author>qq_38049721</author><pubDate>Thu, 08 Jun 2017 00:01:37 +0800</pubDate><description><![CDATA[function checkForm(){
//获取用户名和密码的标签对象
//获取用户名对象
var userObj = document.getElementById("username");
//获取密码对象
var pwdObj = document.getElementById("password");
//获取确密码对象
var queren = document.get]]></description><category></category></item><item><title><![CDATA[HTML]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/72873165</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/72873165</guid><author>qq_38049721</author><pubDate>Tue, 06 Jun 2017 00:18:38 +0800</pubDate><description><![CDATA[用户名
密码
性别男
女
爱好:
抽烟
喝酒
烫头



上传文件:
地址:

北京
河北
河南
省

邯郸
石家庄
郑州

个人简介:

请输入你的个人简介]]></description><category></category></item><item><title><![CDATA[BeanUtils  工具类]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/72855855</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/72855855</guid><author>qq_38049721</author><pubDate>Sat, 03 Jun 2017 23:52:59 +0800</pubDate><description><![CDATA[BeanUtils 是用于简化JavaBean封装数据的操作。它可以给JavaBean封装一个字符串数据，也可以将一个表单提交的所有数据封装到JavaBean中


运用BeanUtils工具类
     1.定义水果类，属性为品种（kind）,价钱（price）;
     2.定义测试类Test，定义Map集合，将name和age赋值，存入到Map集合，然后利用BeanUtils将数]]></description><category></category></item><item><title><![CDATA[三层架构和事务]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/72838232</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/72838232</guid><author>qq_38049721</author><pubDate>Fri, 02 Jun 2017 00:14:09 +0800</pubDate><description><![CDATA[三层构架有web、service（业务层）、数据层。
      Web：包含于web相关的内容，依赖于业务层
      Service：只关心业务逻辑，向数据库中插入一条数据，在数据层就对应                             一个方法，业务层依赖于数据层。
      
事务：
      作用：保证在一个事务中多次操作要么全部都成功，要么全部都失败
 
p]]></description><category></category></item><item><title><![CDATA[JDBC：mysql和eclipse的连接]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/72814587</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/72814587</guid><author>qq_38049721</author><pubDate>Tue, 30 May 2017 23:42:08 +0800</pubDate><description><![CDATA[在数据库中输入：
#创建数据库
CREATE DATABASE day22_JDBC;
#使用数据库
USE day22_JDBC;


#创建分类表
CREATE TABLE sort(
  cid INT PRIMARY KEY AUTO_INCREMENT  ,
  cname VARCHAR(100)
);
#初始化数据
INSERT INTO sort (cna]]></description><category></category></item><item><title><![CDATA[mysql 多表查询]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/72796948</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/72796948</guid><author>qq_38049721</author><pubDate>Mon, 29 May 2017 00:08:07 +0800</pubDate><description><![CDATA[内连接查询(使用的关键字 innerjoin  -- inner可以省略)
隐式内连接：select * fromA,B where 条件;
显示内连接：select * from Ainner join B on 条件;
外连接查询(使用的关键字 outerjoin -- outer可以省略)
左外连接：left outer join
select * from Aleft outer]]></description><category></category></item><item><title><![CDATA[数据库，多对多表约束]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/72776267</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/72776267</guid><author>qq_38049721</author><pubDate>Sat, 27 May 2017 00:07:59 +0800</pubDate><description><![CDATA[#创建数据库
CREATE DATABASE shangdian;


USE shangdian;
#商品表，主表
CREATE TABLE products(
pid VARCHAR(32) PRIMARY KEY,
pname VARCHAR(40),
price DOUBLE,
cid VARCHAR(32)
);
#添加数据
INSERT INTO produc]]></description><category></category></item><item><title><![CDATA[习题，案例]]></title><link>https://blog.youkuaiyun.com/qq_38049721/article/details/72719322</link><guid>https://blog.youkuaiyun.com/qq_38049721/article/details/72719322</guid><author>qq_38049721</author><pubDate>Wed, 24 May 2017 23:58:37 +0800</pubDate><description><![CDATA[根据XML文件，写出javabean。















public class User {
private String userName;
private String password;
public User() {
super();
// TODO Auto-generated constructor stub
}
//省略了]]></description><category></category></item></channel></rss>