老师，我这个填入登录名和密码后就报错，这个怎么改啊

老师还是没有解决，不只有那个错误，打开maven报这个错误怎末回事？

<script>
    function info() {
        console.log('我是XXX');
        console.log('我很会唱歌吖');
        function caiyi() {
            console.log('我可以开始表演才艺');
        }
        return caiyi;
    }
    var result = info();
    result();

</script>

老师您好，我还是不太能理解

    1、在把函数当做返回值的时候才能用到return吗？

    2、info();和给他赋值为result有什么区别，为什么赋值后就可以接收到caiyi()?不太能理解原理

老师我的防火墙关闭了，虚拟机也重启了，还是跟主机的ipping不通，之前用的时候还是可以ping通的

服务端启动正常，客户端启动就报错

package com.yc.server;

import java.io.DataOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.net.ServerSocket;
import java.net.Socket;

public class Server {
    public static void main(String[] args) throws IOException, ClassNotFoundException {
        System.out.println("--------服务器启动---------");
        //创建ServerSocket对象
        ServerSocket sever=new ServerSocket(10000);
        Socket socket=sever.accept();
        //获取输入流，包装成对象流
        ObjectInputStream ois=new ObjectInputStream(socket.getInputStream());
        User user=(User)ois.readObject();
        String str="";
        //对用户和密码验证
        if("name1".equals(user.getUserName())&&"123456".equals(user.getPassWord())){
            str="登陆成功";
        }else{
            str="账号密码不正确";
        }
        //获取输出流，包装成数据流
        DataOutputStream dos=new DataOutputStream(socket.getOutputStream());
        dos.writeUTF(str);
        //关闭流
        if(dos!=null){
            dos.close();
        }
        if(ois!=null){
            ois.close();
        }
        if(socket!=null){
            socket.close();
        }
    }
}

package com.yc.test;
import java.io.DataInputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.net.Socket;
public class Client {
    public static void main(String[] args) throws IOException {
        //创建Socket对象，连接服务器
        Socket client=new Socket("localhost",10000);
        //获取输出流（对象流）
        ObjectOutputStream oos=new ObjectOutputStream(client.getOutputStream());
        //创建User对象
        User u=new User("name1","123456");
        //User对象发送到服务器
        oos.writeObject(u);
        //获取输入流（数据流）
        DataInputStream dis=new DataInputStream(client.getInputStream());
        System.out.println(dis.readUTF());
        if(dis!=null){
            dis.close();
        }
        if(oos!=null){
            oos.close();
        }
        if(client!=null){
            client.close();
        }
    }
}

老师，我这个找不到那个mySql,这个怎么解决

options这个参数是啥意思，怎么用法呢。。。。

老师，我想匹配以@qq.com为结尾的字符串，这段代码哪里有问题，应该怎么修改呀？

import re
s = '123456@qq.com'
pattern1 = '*@qq.com$'
v1=re.match(pattern1,s);print(v1)

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

老师，为什么这里用的是this，不能用父类的名字来调用呢？是不是不同包中，只能通过this和super来调用父类自己被protected修饰的属性和方法？

老师，你的那些资料去哪里能获取呀，程序的安装包，还有ppt那些

老师，这个插入的结果是失败，不成功，已经尝试过很多次，不知道哪里出问题了

老师，请问，我们之前学的位置参数和命名参数，x,y传给m,n按照位置，这里的t为什么刚好是传入的task呢

老师，您好，请问在创建P1变量的时候，为甚么说P1是占4个字节？