学了这次的视频，我了解了下一直不太懂的命名空间

命名空间的出现是为了解决dtd不能解决的xml的命名冲突问题，这次课的视频里，xsd文件没有定义自己的命名空间。

然后在book.xml中引入book.xsd的时候属性使用的是

xsi:noNamespaceSchemaLocation="book.xsd"

不指定命名空间，只指定用于模式校验的xsd文档的位置，这种写法，XML模式处理器已经可以校验到xml里的写法问题了。如图：具体报错：

The content of element 'book' is not complete. One of '{price}' is expected.

说明已经检验成功了

在这里老师用的是

xsi:noNamespaceSchemaLocation="{book.xsd}" 而这种写法在我的idea里面是报红的。 至于视频里老师不报红，我猜测不同工具的不同文件，可能工具没有识别出来语法错误，把验证插件给关闭了。为什么老师要多此一举，使用java的相关类，SchemaFactory进行解析， 是不是因为要让我们了解如果脱离eclipse或者相关IDE，没有XML解析器，在只有xml文件及xsd文件的基础上，java也可以完成使用schema对xml文档的校验。

（扩充：自己测试了一下似乎谷歌浏览器无法完成使用schema对xml文档的校验，不报任何错误。）

这点在视频里没有提到。。这里存在疑问：（******） 

    FileReader reader = null;

7        try {

8            reader = new FileReader("d:/a.txt");

9            char c = (char) reader.read();

10            char c2 = (char) reader.read();

11            System.out.println("" + c + c2);

12        } catch (FileNotFoundException e) {

13            e.printStackTrace();

14        } catch (IOException e) {

15            e.printStackTrace();

16        } finally {

17            try {

''''''

老师   在捕获异常机制-try-catch-finally时老师创建了记事本  里面只有abc三个字母    然后用三个这样的

char c = (char) reader.read()语句读取了这三个字母，那如果有很多很多个字母或其他的内容 应该怎么做呢

input标签里常有name属性，而div标签里常有class属性，但是input标签里也有class属性，这个class属性是干啥的？我一直以为class属性就是name属性的意思一样，就是取名字，但是为什么有时候input标签里要同时出现name和class,这个class属性到底是干什么用的？或者classs属性到底表示什么意思？

有一个疑问题目是返回复制后复杂链表的首节点，为什么还要走第三步，把它们拆分后再返回，直接到第二步直接返回不就行了？还是我对题目有误解？

老师，我发现这样也能读到函数内部声明的变量，这样用是不是更方便一点。

老师，尝试登录的时候提供的手机号和密码都是正确存在的，总是提示下面的错误。非说是用户名或密码不正确。然后跟着后面一大串的exception.我实在是找不到原因了，项目都重新写了一遍了。救救我吧。。。

Creating a new SqlSession

SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@5e1f02bc] was not registered for synchronization because synchronization is not active

JDBC Connection [com.mysql.cj.jdbc.ConnectionImpl@3d8d450] will not be managed by Spring

==>  Preparing: SELECT user_id,dept_id,user_name,user_type,sex,age,picture,background,phone,email,strong,honor,introduction,user_rank,`password`,last_login_time,last_login_ip,`status`,union_id,open_id,create_time,update_time,create_by,update_by,salt,del_flag,scheduling_flag FROM sys_user WHERE (phone = ?) 

==> Parameters: 13888001004(String)

<==    Columns: user_id, dept_id, user_name, user_type, sex, age, picture, background, phone, email, strong, honor, introduction, user_rank, password, last_login_time, last_login_ip, status, union_id, open_id, create_time, update_time, create_by, update_by, salt, del_flag, scheduling_flag

<==        Row: 5, 104, 华佗, 1, 1, 22, , 4, 13888001004, his4@163.com, 全科, 神医, <<BLOB>>, 1, 520a5b05dbec9f937f70092e088058e8, 2018-03-16 11:33:00, 127.0.0.1, 0, null, null, 2018-03-16 11:33:00, 2020-04-30 00:49:52, admin, 超级管理员, 91D53B3C4B8E40C7BA3613E41546AAE1, 0, 0

<==      Total: 1

Closing non transactional SqlSession [org.apache.ibatis.session.defaults.DefaultSqlSession@5e1f02bc]

2020-08-30 04:10:56.275 ERROR 34210 --- [nio-8080-exec-1] c.b.controller.system.LoginController    : 用户名或密码不正确

redis.clients.jedis.exceptions.JedisConnectionException: Could not get a resource from the pool

at redis.clients.jedis.util.Pool.getResource(Pool.java:59) ~[jedis-3.1.0.jar:na]

at redis.clients.jedis.JedisPool.getResource(JedisPool.java:234) ~[jedis-3.1.0.jar:na]

at org.crazycake.shiro.RedisManager.getJedis(RedisManager.java:35) ~[shiro-redis-3.2.3.jar:na]

at org.crazycake.shiro.WorkAloneRedisManager.set(WorkAloneRedisManager.java:71) ~[shiro-redis-3.2.3.jar:na]

at org.crazycake.shiro.RedisSessionDAO.saveSession(RedisSessionDAO.java:90) ~[shiro-redis-3.2.3.jar:na]

at org.crazycake.shiro.RedisSessionDAO.doCreate(RedisSessionDAO.java:131) ~[shiro-redis-3.2.3.jar:na]

at org.apache.shiro.session.mgt.eis.AbstractSessionDAO.create(AbstractSessionDAO.java:116) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.session.mgt.DefaultSessionManager.create(DefaultSessionManager.java:177) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.session.mgt.DefaultSessionManager.doCreateSession(DefaultSessionManager.java:158) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.session.mgt.AbstractValidatingSessionManager.createSession(AbstractValidatingSessionManager.java:136) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.session.mgt.AbstractNativeSessionManager.start(AbstractNativeSessionManager.java:99) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.mgt.SessionsSecurityManager.start(SessionsSecurityManager.java:152) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.subject.support.DelegatingSubject.getSession(DelegatingSubject.java:336) [shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.subject.support.DelegatingSubject.getSession(DelegatingSubject.java:312) [shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.mgt.DefaultSubjectDAO.mergePrincipals(DefaultSubjectDAO.java:204) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.mgt.DefaultSubjectDAO.saveToSession(DefaultSubjectDAO.java:166) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.mgt.DefaultSubjectDAO.save(DefaultSubjectDAO.java:147) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.mgt.DefaultSecurityManager.save(DefaultSecurityManager.java:383) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.mgt.DefaultSecurityManager.createSubject(DefaultSecurityManager.java:350) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.mgt.DefaultSecurityManager.createSubject(DefaultSecurityManager.java:183) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.mgt.DefaultSecurityManager.login(DefaultSecurityManager.java:283) ~[shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.subject.support.DelegatingSubject.login(DelegatingSubject.java:256) [shiro-core-1.3.2.jar:1.3.2]

at com.bjsxt.controller.system.LoginController.login(LoginController.java:65) ~[classes/:na]

at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_211]

at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_211]

at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_211]

at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_211]

at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190) [spring-web-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138) [spring-web-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:105) [spring-webmvc-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:879) [spring-webmvc-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793) [spring-webmvc-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) [spring-webmvc-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040) [spring-webmvc-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943) [spring-webmvc-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) [spring-webmvc-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) [spring-webmvc-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at javax.servlet.http.HttpServlet.service(HttpServlet.java:634) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) [spring-webmvc-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at javax.servlet.http.HttpServlet.service(HttpServlet.java:741) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:112) [shiro-web-1.5.3.jar:1.5.3]

at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:358) [spring-web-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:271) [spring-web-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) [tomcat-embed-websocket-9.0.33.jar:9.0.33]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:61) [shiro-web-1.5.3.jar:1.5.3]

at org.apache.shiro.web.servlet.AdviceFilter.executeChain(AdviceFilter.java:108) [shiro-web-1.5.3.jar:1.5.3]

at org.apache.shiro.web.servlet.AdviceFilter.doFilterInternal(AdviceFilter.java:137) [shiro-web-1.5.3.jar:1.5.3]

at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) [shiro-web-1.5.3.jar:1.5.3]

at org.apache.shiro.web.servlet.ProxiedFilterChain.doFilter(ProxiedFilterChain.java:66) [shiro-web-1.5.3.jar:1.5.3]

at org.apache.shiro.web.servlet.AbstractShiroFilter.executeChain(AbstractShiroFilter.java:449) [shiro-web-1.5.3.jar:1.5.3]

at org.apache.shiro.web.servlet.AbstractShiroFilter$1.call(AbstractShiroFilter.java:365) [shiro-web-1.5.3.jar:1.5.3]

at org.apache.shiro.subject.support.SubjectCallable.doCall(SubjectCallable.java:90) [shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.subject.support.SubjectCallable.call(SubjectCallable.java:83) [shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.subject.support.DelegatingSubject.execute(DelegatingSubject.java:383) [shiro-core-1.3.2.jar:1.3.2]

at org.apache.shiro.web.servlet.AbstractShiroFilter.doFilterInternal(AbstractShiroFilter.java:362) [shiro-web-1.5.3.jar:1.5.3]

at org.apache.shiro.web.servlet.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:125) [shiro-web-1.5.3.jar:1.5.3]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) [spring-web-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) [spring-web-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) [spring-web-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) [spring-web-5.2.5.RELEASE.jar:5.2.5.RELEASE]

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:139) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:373) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1594) [tomcat-embed-core-9.0.33.jar:9.0.33]

at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-9.0.33.jar:9.0.33]

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_211]

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_211]

at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-9.0.33.jar:9.0.33]

at java.lang.Thread.run(Thread.java:748) [na:1.8.0_211]

Caused by: redis.clients.jedis.exceptions.JedisDataException: WRONGPASS invalid username-password pair

at redis.clients.jedis.Protocol.processError(Protocol.java:132) ~[jedis-3.1.0.jar:na]

at redis.clients.jedis.Protocol.process(Protocol.java:166) ~[jedis-3.1.0.jar:na]

at redis.clients.jedis.Protocol.read(Protocol.java:220) ~[jedis-3.1.0.jar:na]

at redis.clients.jedis.Connection.readProtocolWithCheckingBroken(Connection.java:318) ~[jedis-3.1.0.jar:na]

at redis.clients.jedis.Connection.getStatusCodeReply(Connection.java:236) ~[jedis-3.1.0.jar:na]

at redis.clients.jedis.BinaryJedis.auth(BinaryJedis.java:2229) ~[jedis-3.1.0.jar:na]

at redis.clients.jedis.JedisFactory.makeObject(JedisFactory.java:119) ~[jedis-3.1.0.jar:na]

at org.apache.commons.pool2.impl.GenericObjectPool.create(GenericObjectPool.java:889) ~[commons-pool2-2.7.0.jar:2.7.0]

at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:424) ~[commons-pool2-2.7.0.jar:2.7.0]

at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:349) ~[commons-pool2-2.7.0.jar:2.7.0]

at redis.clients.jedis.util.Pool.getResource(Pool.java:50) ~[jedis-3.1.0.jar:na]

... 91 common frames omitted

那个本机ip是指什么ip，不是虚拟机的ip么

老师你好

1、图中这个变量taxableIncome还未初始化，也能正常使用。是否因为它是成员变量，会默认初始化。

2、那么在方法中局部变量不会默认初始化，如果声明一个变量的值由其他变量计算所得时，而其他变量的值还未初始化怎么办，这个情况应该怎么处理？改变代码的执行顺序吗？

3、所有代码都是由上往下执行的吗？有哪些代码是优先执行的？

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Ajax案例</title>
</head>
<body>
 <span>用户名：</span><input type="text" class="username">
 <span>密码：</span><input type="text" class="password">
 <button class="button">点击</button>
 <script>
     $('button').click(function () {
        $.ajax({
          //请求方式
           type:'post',
          //交互数据格式为JSON
          dataType:'json',
          //指明请求发送到PHP后台的地址
          url:'777.php',
          data:{
               myName:$('.username').val(),
               myPass:$('.password').val(),
          },
          success:function (res) {
             if(res.index==0){
             alert('登录失败')
          }else {
                 alert('登录成功')
             }
          },
      });

  });
 </script>
</body>
</html>

<?php
  $username=$post_['myName'];
  $password=$post_['myPass'];
  $success=array['msg'=>'ok'],;
  if($username==beixi && $password==123456){
   $success['index']=1;
  }else{
   $success['index']=0 ;
  }
  echo json_encode($success);
？>  老师麻烦看一下哪里不对啊？谢谢老师

老师，取馒头和放馒头的方法分别放在消费者和生产者类中可以吗？还是必须要放在缓冲区啊

老师，time.time()返回的值是以秒为单位，带微秒精度的浮点值是不是意思就是，小数点后面可以有6位数呢？

关于伪对象选择器

.div_2:before{
				content: "我们的祖国是花园";
			}

<div class="div_2">
        	你好
        </div>

用这样子写出来的content爬虫可以拿到么,

为什么有些网页里的内容用浏览器代理也爬不到东西

老师，单个dml操作用上事务管理是不是意义不大，因为单个数据库的增删改如果发生错误的话就不会对数据成功的增删改操作。

老师你好，我有个疑问？为什么父项目不能像api模块那样直接引入到consumer呢？而是要但是像老师那样去引入。图一是老师的引入方式在打包环节没有错误，图二是我的引入方式，在打包环节会出错，该为和老师一样就不会出错？这是为什么呢，还是说pom项目和jar项目的依赖方式是不同的？pom项目如果不能通过parent标签引入，是不是就只能像老师这样引入而不能向我这样引入呢？