<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[YtN_C的博客]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/YtN_C</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; YtN_C]]></copyright><item><title><![CDATA[Mybatis是如何防止sql注入的]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79455969</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79455969</guid><author>YtN_C</author><pubDate>Tue, 06 Mar 2018 11:45:54 +0800</pubDate><description><![CDATA[答:采用预编译的方式防止sql注入.但也不是完全会防住,能不能完全防住取决于mybatis使用者水平.原理是怎样的呢?我们分析一下:当我们执行Mybatis中写的sql语句时,会出现以下提示SELECT * FROM user WHERE id = ? 这时候其实Mybatis已经进行了预编译,我们不管传什么东西,都只会去替换占位符,比如我们传输一个AND,结果就会为:SELECT * FROM ...]]></description><category></category></item><item><title><![CDATA[Hashmap中的向上转型]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79450349</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79450349</guid><author>YtN_C</author><pubDate>Mon, 05 Mar 2018 20:11:37 +0800</pubDate><description><![CDATA[向上转型体现多态,向下转型就是强转.  例子:public class Reference {
    public static void main(String[] args) {

        HashMap&amp;lt;String,Object&amp;gt; hashMap = new HashMap&amp;lt;&amp;gt;();
        hashMap.put(&quot;1&quot;,new Referenc...]]></description><category></category></item><item><title><![CDATA[toString,valueOf与(String)的联系和区别]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79450240</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79450240</guid><author>YtN_C</author><pubDate>Mon, 05 Mar 2018 20:08:05 +0800</pubDate><description><![CDATA[toString是Object类的一个方法,所有类都有它.如果不重写该方法的情况下,默认输出如下所示:public String toString() {
        return getClass().getName() + &quot;@&quot; + Integer.toHexString(hashCode());
    }valueOf是包装类型的一个方法(比如Integer等),但是跟进它发现,实际...]]></description><category></category></item><item><title><![CDATA[Java中深层复制和浅层复制]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79354559</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79354559</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 16:46:51 +0800</pubDate><description><![CDATA[什么是深层和浅层复制?浅层复制是把新的引用指向目标对象.例如:Object a = new Object();

Object b = a;//这就是浅层复制深层复制是直接新建一个和目标对象一模一样的东西.常用实现方式有对象的clone(),List的addAll(),Map的putAll()和Apache的工具类BeanUtils.copyProperties() ...]]></description><category></category></item><item><title><![CDATA[ajax不能用作导出]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79353825</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79353825</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 15:13:58 +0800</pubDate><description><![CDATA[导出不能使用ajax,否则不会出现下载的情况,但是打开chromeF12依然会看到数据成功返回.导出的时候老老实实用submit提交一下就可以了.]]></description><category></category></item><item><title><![CDATA[finalize函数的调用]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79353777</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79353777</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 15:08:28 +0800</pubDate><description><![CDATA[finalize()是由JVM自动调用的，你可以用System.gc()，但JVM不一定会立刻执行，JVM感觉内存空间有限时，才会开始执行finalize()，至于新的对象创建个数和被收集个数不同是因为收集的对象只和JVM的垃圾收集策略有关。(1) finalize()函数是干嘛的？Java不是有Garbage Collection(以下简称gc)来负责回收内存吗？gc只能清除在堆上分配的内存（纯...]]></description><category></category></item><item><title><![CDATA[java一个文件中定义多个类]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79353758</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79353758</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 15:07:49 +0800</pubDate><description><![CDATA[一个文件定义多个类?      一个.java源文件中可以有多个类吗？（内部类除外）有什么条件？带着这个疑惑，动手建几个测试类，揭开心中的疑惑。以下是解开疑惑过程：  package test;
/**
 * 一个.java源文件中可以有多个类吗？（内部类除外）有什么条件？ 
 * 可以的   
 *但是只能有一个public类, 而且如果有public类的话，这个文件的名字要和这个类的名字一样。...]]></description><category></category></item><item><title><![CDATA[idea创建多module]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79353745</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79353745</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 15:06:17 +0800</pubDate><description><![CDATA[project下可以创建多module,每个module都是独立的gradle的使用其他module的方式project下可以创建多module,每个module都是独立的
gradle的使用其他module的方式
dependencies {
	compile project(&quot;:fcs-core&quot;)
	compile project(&quot;:fcs-dubbo&quot;)
}maven是&amp;lt;depen...]]></description><category></category></item><item><title><![CDATA[EL表达式中param和requestScope的区别]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79353731</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79353731</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 15:05:10 +0800</pubDate><description><![CDATA[①request.getParameter(“username”)等价于${param.username }，它们一般用在服务器获取页面或客户端的内容，这些内容都是String的；②request.getAttribute(“username”)等价于${requestScope.username}，一般是从服务器传递数据到页面，在页面中获取服务器保存在其中的数据内容。...]]></description><category></category></item><item><title><![CDATA[xml格式与标签]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79353704</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79353704</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 15:02:41 +0800</pubDate><description><![CDATA[xmlns,命名空间.什么都不带则表示默认命名空间为namespaceURI,xmlns:namespace-prefix=&quot;namespaceURI&quot;而带东西的:这个 XML 文档携带着某个表格中的信息：&amp;lt;h:table xmlns:h=&quot;http://www.w3.org/TR/html4/&quot;&amp;gt;   &amp;lt;h:tr&amp;gt;   &amp;lt;h:td&amp;gt;Apples&amp;lt;/h:t...]]></description><category></category></item><item><title><![CDATA[mybatis技巧备忘]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79353690</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79353690</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 15:01:27 +0800</pubDate><description><![CDATA[做个备忘: xml特殊符号转义写法    &amp;amp;lt;          &amp;lt;     &amp;amp;gt;          &amp;gt;      &amp;amp;lt;&amp;amp;gt;   &amp;lt;&amp;gt;    &amp;amp;amp;      &amp;amp;     &amp;amp;apos;      '    &amp;amp;quot;      &quot;也可以使用&amp;lt;![CDATA[ ]]&amp;gt;符]]></description><category></category></item><item><title><![CDATA[bootstrap插件]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79353569</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79353569</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 15:00:07 +0800</pubDate><description><![CDATA[datetimepicker插件:时间格式要带 &quot;-&quot; 否则跳到选择的时候1988年.(包括后端传值和前端修改) $(&quot;#firstTime&quot;).datetimepicker({
            format: 'yyyy-mm',
            weekStart: 1,
            autoclose: true,
            startView: 3...]]></description><category></category></item><item><title><![CDATA[LinkedHashmap的使用]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79353344</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79353344</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 14:48:48 +0800</pubDate><description><![CDATA[工作中遇到了这么一种情况:从Excel中读取到的数据需要去做校验,校验出错的会有一个HashMap存储出错的行号和出错信息,循环是顺序的,也就是说从第一行开始,但是在网页上输出HashMap的错误信息的时候却不是顺序输出.比如1,2,6,9行出错,但是网页上显示的顺序可能为2,6,1,9.解决方法是使用LinkedHashmap储存出错信息.因为LinkedHashmap是有序的.看网上有人分析是...]]></description><category></category></item><item><title><![CDATA[springboot中jsp报错404]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79352409</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79352409</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 11:44:30 +0800</pubDate><description><![CDATA[spirngboot 404：1.jsp解析包未引入        &amp;lt;dependency&amp;gt;
            &amp;lt;groupId&amp;gt;org.apache.tomcat.embed&amp;lt;/groupId&amp;gt;
            &amp;lt;artifactId&amp;gt;tomcat-embed-jasper&amp;lt;/artifactId&amp;gt;
        &amp;lt...]]></description><category></category></item><item><title><![CDATA[jsp和freemarker双view显示]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79352349</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79352349</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 11:37:47 +0800</pubDate><description><![CDATA[我的目录结构如上.两个个关键的配置文件:spring-mvc.xml和web.xml&amp;lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&amp;gt;
&amp;lt;beans xmlns=&quot;http://www.springframework.org/schema/beans&quot;
       xmlns:xsi=&quot;http://www.w3.org/2001/XMLSchema-...]]></description><category></category></item><item><title><![CDATA[mysql大小写敏感问题]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79352232</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79352232</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 11:26:21 +0800</pubDate><description><![CDATA[linux下mysql区分大小写(数据库名,表名,字段名)windows下不区分大小写(数据库名,表名,字段名)原因:和操作系统本身有关系.因为linux创建文件时区分大小写,即A.txt和a.txt可以在一个文件夹下;而windows则不区分,当已经存在A.txt时,再创建a.txt,会提示已经存在.show variables like '%case%';这句话是查看mysq大小写敏感开关是否...]]></description><category></category></item><item><title><![CDATA[java中Enum本质]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79351504</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79351504</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 10:31:26 +0800</pubDate><description><![CDATA[Enum本质是静态成员变量.public enum  Enum {

A(1,2),B(1,2);
int a;
int b;


    Enum(int i, int i1) {
        this.a = i;
        this.b = i1;
    }

}
以上代码经过javap反编译,得到结果为:public final class Enum extends java....]]></description><category></category></item><item><title><![CDATA[静态代码块,静态变量,构造函数和构造代码块的执行顺序]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79351414</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79351414</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 10:26:26 +0800</pubDate><description><![CDATA[先静态再非静态.静态代码块和静态变量谁先谁后看定义的顺序.构造代码块先于构造函数执行.public class MockEnum{


    private String id;
    private String name;
    
    static {
        System.out.println(&quot;测试&quot;);
    }
    public final static Mo...]]></description><category></category></item><item><title><![CDATA[idea远程调试]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79351300</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79351300</guid><author>YtN_C</author><pubDate>Fri, 23 Feb 2018 10:15:07 +0800</pubDate><description><![CDATA[1.若项目已经启动先关闭项目.2.在tomcat的bin文件夹下的Catalina.sh添加JAVA_OPTS=&quot;$JAVA_OPTS -Xdebug -Xrunjdwp:transport=dt_socket,suspend=n,server=y,address=5555&quot;.以上端口号为5555.3.在idea中打开Edit Configuration,点击加号选择Remote,将远程ip和端口...]]></description><category></category></item><item><title><![CDATA[js和jdk小知识]]></title><link>https://blog.youkuaiyun.com/YtN_C/article/details/79348444</link><guid>https://blog.youkuaiyun.com/YtN_C/article/details/79348444</guid><author>YtN_C</author><pubDate>Thu, 22 Feb 2018 17:07:02 +0800</pubDate><description><![CDATA[js ajax如何传输数组：前端：  traditional：true后端：  request.getParameterValues()导出内存分析文件jmap dump:file=XXXXX.hropfjdk自带好多有趣的工具：jcontrol和jvisualvm...]]></description><category></category></item></channel></rss>