<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[Wchenyang的博客]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/Wchenyang</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; Wchenyang]]></copyright><item><title><![CDATA[java报错]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/72457734</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/72457734</guid><author>Wchenyang</author><pubDate>Thu, 18 May 2017 09:53:41 +0800</pubDate><description><![CDATA[org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'documentationPluginsBootstrapper' defined in URL [jar:file:/E:/maven/repository/io/springfox/springfox-]]></description><category></category></item><item><title><![CDATA[java父类强转成子类]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/71275191</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/71275191</guid><author>Wchenyang</author><pubDate>Sat, 06 May 2017 18:27:25 +0800</pubDate><description><![CDATA[java将父类转换成子类，是为了拓展更宽泛的使用，子类可以转换成父类，赋予其功能，试想在实际项目中，用一个对象接到所有参数，它既是父类，在将他赋值给一个子类，那么这个子类便用有了自己的生命，便可以去行使功能，而这个父类可以继续强转成子类，而第二个子类又拥有了自己的生命，便可以去行使功能，而这两个子类之间，又是相互独立的两个类，有这截然不同的功能，但又这相似的能力。]]></description><category></category></item><item><title><![CDATA[openssl  的使用]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/71195076</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/71195076</guid><author>Wchenyang</author><pubDate>Fri, 05 May 2017 13:19:10 +0800</pubDate><description><![CDATA[直接下载openssl.exe  自己建一个bin, 把它放到下面，然后每次使用操作指令，下面就会生成private.pem和public.pem,文件分别是公匙和私]]></description><category></category></item><item><title><![CDATA[数据库被删除了我们怎样做]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/70696123</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/70696123</guid><author>Wchenyang</author><pubDate>Tue, 25 Apr 2017 11:31:15 +0800</pubDate><description><![CDATA[flashback table table_name to timestamp systimestamp-1; (systimestamp-1 这里表示恢复到前一天)]]></description><category></category></item><item><title><![CDATA[sql 语句多个字段连接查询]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/70544138</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/70544138</guid><author>Wchenyang</author><pubDate>Sun, 23 Apr 2017 20:01:02 +0800</pubDate><description><![CDATA[方法一

MySQL在做多字段模糊查询的时候用的语句是
select * from tablename where concat(name,brand) like '%关键词%' 11

concat的 作用是 将多条字段拼成字符串。 
结果发现有些条目查询不出来

问题是 
concat（）中有任何参数是null 则返回为空

解决办法 
1、把null的条目让他不是nu]]></description><category></category></item><item><title><![CDATA[subString  截取字符串]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/70257339</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/70257339</guid><author>Wchenyang</author><pubDate>Thu, 20 Apr 2017 13:12:39 +0800</pubDate><description><![CDATA[str.subString(int  startindex,int   endindex);
他的意思就是startindex,到endindex   下标之间的长度]]></description><category></category></item><item><title><![CDATA[时间日期进行转换]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/70240172</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/70240172</guid><author>Wchenyang</author><pubDate>Wed, 19 Apr 2017 14:31:30 +0800</pubDate><description><![CDATA[public class Time {
 public static String formatDateTime(long mss) {
  String DateTimes = null;
  long days = mss / ( 60 * 60 * 24);
  long hours = (mss % ( 60 * 60 * 24)) / (60 * 60);
  long min]]></description><category></category></item><item><title><![CDATA[对数据进行转码]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/70230860</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/70230860</guid><author>Wchenyang</author><pubDate>Tue, 18 Apr 2017 17:43:12 +0800</pubDate><description><![CDATA[String messageContent = new String(request.getParameter("messageContent").getBytes("iso-8859-1"),"utf-8");]]></description><category></category></item><item><title><![CDATA[uuid的自动生成]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/70229579</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/70229579</guid><author>Wchenyang</author><pubDate>Tue, 18 Apr 2017 16:14:16 +0800</pubDate><description><![CDATA[/**
 * 
 * @author 辰
 *
 */
public class UUCode {
public static void main(String[] args){

  System.out.println(Stringrandom());  
      System.out.println(subStringrandomUUID());
      Syst]]></description><category></category></item><item><title><![CDATA[java 重定向问题   主要用来解决图片的上传问题]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/70213552</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/70213552</guid><author>Wchenyang</author><pubDate>Mon, 17 Apr 2017 17:00:30 +0800</pubDate><description><![CDATA[@RequestMapping("/toWecome")
     public void forwardToWecome(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException{
     request.getRequestDispatcher("/WEB-I]]></description><category></category></item><item><title><![CDATA[jsonp代码格式转换]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/70212637</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/70212637</guid><author>Wchenyang</author><pubDate>Mon, 17 Apr 2017 16:01:28 +0800</pubDate><description><![CDATA[@RequestMapping(value="/pagealltype",method={RequestMethod.GET,RequestMethod.POST})
public   void  pagealltype(HttpServletRequest  request,HttpServletResponse  response) throws IOException{
  String]]></description><category></category></item><item><title><![CDATA[jsonP解决跨域]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/70211758</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/70211758</guid><author>Wchenyang</author><pubDate>Mon, 17 Apr 2017 15:25:43 +0800</pubDate><description><![CDATA[/**
 * 非借不读类型所有数据
 * @return
* @throws IOException 
 */

@RequestMapping(value="/pagealltype",method={RequestMethod.GET,RequestMethod.POST})
public   void  pagealltype(HttpServletRequest  reque]]></description><category></category></item><item><title><![CDATA[对于java工程师来说web才是最锻炼的]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/68947547</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/68947547</guid><author>Wchenyang</author><pubDate>Sat, 01 Apr 2017 19:57:22 +0800</pubDate><description><![CDATA[选在普遍认为app比web重要，那是肯定，但是对于一个程序员的专业素养来说，javaweb是必须重视的，对于我们程序员的提高来说,javaweb才是适合我们成长的最佳选择，如果当app和javaweb在一起时，我们最好选javaweb.]]></description><category></category></item><item><title><![CDATA[自己写项目才是最快的]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/68947536</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/68947536</guid><author>Wchenyang</author><pubDate>Sat, 01 Apr 2017 19:53:29 +0800</pubDate><description><![CDATA[要想进步快，唯一的办法就是自己写很多项目，因为人是很懒的，只有你自己独立负责一款项目的开发时才是最快的。]]></description><category></category></item><item><title><![CDATA[直接排序之经典自我解析]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/66472919</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/66472919</guid><author>Wchenyang</author><pubDate>Sun, 26 Mar 2017 11:25:21 +0800</pubDate><description><![CDATA[public class SelectSort1 {


public static void main(String[] args) {


int[] len = { 12, 23, 45, 56, 768, 2 };


SelectSort1 sort = new SelectSort1();
sort.soter(len);
}


private void ]]></description><category></category></item><item><title><![CDATA[反转排序  自我经典理解]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/66472656</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/66472656</guid><author>Wchenyang</author><pubDate>Sun, 26 Mar 2017 10:53:53 +0800</pubDate><description><![CDATA[public class ReverSort1 {


public static void main(String[] args){

int array[]={11,22,33,44,55,66,77};
ReverSort1  sort=new ReverSort1();

sort.serter(array);


}


/**
* 反转排序
* @par]]></description><category></category></item><item><title><![CDATA[冒泡排序自我经典解析]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/66472427</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/66472427</guid><author>Wchenyang</author><pubDate>Sun, 26 Mar 2017 10:24:07 +0800</pubDate><description><![CDATA[public class MessageUtils {

public static  void  main(String []  args){


//先定义一个数组
int [] array={63,4,24,1,3,15};

//给这个数组定义一个对象
MessageUtils  sortor=new  MessageUtils();

//通过这个对象调用自定义的方]]></description><category></category></item><item><title><![CDATA[RBAC权限管理]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/61420346</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/61420346</guid><author>Wchenyang</author><pubDate>Sat, 11 Mar 2017 16:33:50 +0800</pubDate><description><![CDATA[RBAC权限管理
RBAC(Role-Based  Access  Control,基于角色的访问控制),就是用户通过角色与权限进行关联。而用户，角色，权限三者之间分别是多对多，多对多，多对多对多关系，简单的说，一个用户拥有若干个角色，一个角色可能是多个用户，它们两个通过一张主键表关联起来，形成多对多，一个角色拥有若干个权限，一个权限也被多个角色所拥有，它们两个通过一张主键表关联起来，形成多对多]]></description><category></category></item><item><title><![CDATA[insert   sql]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/60474259</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/60474259</guid><author>Wchenyang</author><pubDate>Sun, 05 Mar 2017 20:14:15 +0800</pubDate><description><![CDATA[如何一次插入多条记录的SQL语句？ 













在使用SQL数据库的时候，我们也许会需要一次像数据库中添加多条记录，那么我们可以使用SQL语句来实现，该语句具体如下：
--添加一条记录    
INSERT INTO tableName(col1,col2,col3) VALUES (1,2,3)    
   
--添加多条记录    
INSERT ]]></description><category></category></item><item><title><![CDATA[java字符串的替换replace、replaceAll、replaceFirst的区别详解]]></title><link>https://blog.youkuaiyun.com/Wchenyang/article/details/59519611</link><guid>https://blog.youkuaiyun.com/Wchenyang/article/details/59519611</guid><author>Wchenyang</author><pubDate>Thu, 02 Mar 2017 15:00:03 +0800</pubDate><description><![CDATA[摘要: String类的replace、replaceAll、replaceFirst的区别详解；涉及到正则表达式。


如果不是刚刚复习了下正则表达式，我可能也不会注意到，原来String的replaceAll跟replaceFirst用到了正则表达式！
不多解释，看代码：
String s = "my.test.txt";
System.out.println(s.replace("]]></description><category></category></item></channel></rss>