def my_avg(a,b):
    return(a+b)/2
c = my_avg(10,4)
print(int(c))

老师有一个小疑问，第三行，如果没有赋值变量C，直接调用 my_avg(10,4),什么都打印不出来。函数体不是可以直接调用的吗？

def dai_li_66(page):

    web = WebRequest()

    for i in range(1,page+1):

        url = f"http://www.66ip.cn/{i}.html"

        web.get(url=url)

        e = web.get_tree()

        # 解析数据

        ips = e.xpath('//*[@id="main"]/div[1]/div[2]/div[1]/table/tbody/tr/td[1]/text()')

        ports = e.xpath('//*[@id="main"]/div[1]/div[2]/div[1]/table/tbody/tr/td[2]/text()')

        print(ips)

        for i_,p in zip(ips,ports):

            print({'ip':i_,'port':p,"_type":'http'})

        sleep(3)

为啥返回的是一个空列表呢？

老师，我想问下，这个addTwo()方法和ReturnOneParam接口是实现关系吗？

为什莫我按老师的编码打出来是这样的结果，哪里出错了呢

parseInt 用法之前没讲过，之后会讲吗

如果前面的已用闭包开发了新功能，那后面又要增加新功能，那如何再用闭包来开发呀？

老师我为啥自定义了指令 当Life组件中点击改变按钮时候的P元素 会渲染而且字体应该是黄色 为啥不生效  

老师，起初是报错，

Failed to configure a DataSource: 'url' attribute is not specified and no embedd

上网查了之后添加了自动配置：@SpringBootApplication(exclude= {DataSourceAutoConfiguration.class})

然后现在报错如下：

"D:\工作软件\IntelliJ IDEA 2020.1\jbr\bin\java.exe" -XX:TieredStopAtLevel=1 -noverify -Dspring.output.ansi.enabled=always -Dcom.sun.management.jmxremote -Dspring.jmx.enabled=true -Dspring.liveBeansView.mbeanDomain -Dspring.application.admin.enabled=true "-javaagent:D:\工作软件\IntelliJ IDEA 2020.1\lib\idea_rt.jar=53223:D:\工作软件\IntelliJ IDEA 2020.1\bin" -Dfile.encoding=UTF-8 -classpath X:\Java学习\springboot_text\mybatis_demo\target\classes;X:\repository\org\springframework\boot\spring-boot-starter-thymeleaf\2.4.4\spring-boot-starter-thymeleaf-2.4.4.jar;X:\repository\org\springframework\boot\spring-boot-starter\2.4.4\spring-boot-starter-2.4.4.jar;X:\repository\org\springframework\boot\spring-boot\2.4.4\spring-boot-2.4.4.jar;X:\repository\org\springframework\boot\spring-boot-autoconfigure\2.4.4\spring-boot-autoconfigure-2.4.4.jar;X:\repository\org\springframework\boot\spring-boot-starter-logging\2.4.4\spring-boot-starter-logging-2.4.4.jar;X:\repository\ch\qos\logback\logback-classic\1.2.3\logback-classic-1.2.3.jar;X:\repository\ch\qos\logback\logback-core\1.2.3\logback-core-1.2.3.jar;X:\repository\org\apache\logging\log4j\log4j-to-slf4j\2.13.3\log4j-to-slf4j-2.13.3.jar;X:\repository\org\apache\logging\log4j\log4j-api\2.13.3\log4j-api-2.13.3.jar;X:\repository\org\slf4j\jul-to-slf4j\1.7.30\jul-to-slf4j-1.7.30.jar;X:\repository\jakarta\annotation\jakarta.annotation-api\1.3.5\jakarta.annotation-api-1.3.5.jar;X:\repository\org\yaml\snakeyaml\1.27\snakeyaml-1.27.jar;X:\repository\org\thymeleaf\thymeleaf-spring5\3.0.12.RELEASE\thymeleaf-spring5-3.0.12.RELEASE.jar;X:\repository\org\thymeleaf\thymeleaf\3.0.12.RELEASE\thymeleaf-3.0.12.RELEASE.jar;X:\repository\org\attoparser\attoparser\2.0.5.RELEASE\attoparser-2.0.5.RELEASE.jar;X:\repository\org\unbescape\unbescape\1.1.6.RELEASE\unbescape-1.1.6.RELEASE.jar;X:\repository\org\slf4j\slf4j-api\1.7.30\slf4j-api-1.7.30.jar;X:\repository\org\thymeleaf\extras\thymeleaf-extras-java8time\3.0.4.RELEASE\thymeleaf-extras-java8time-3.0.4.RELEASE.jar;X:\repository\org\mybatis\spring\boot\mybatis-spring-boot-starter\2.1.4\mybatis-spring-boot-starter-2.1.4.jar;X:\repository\org\springframework\boot\spring-boot-starter-jdbc\2.4.4\spring-boot-starter-jdbc-2.4.4.jar;X:\repository\com\zaxxer\HikariCP\3.4.5\HikariCP-3.4.5.jar;X:\repository\org\springframework\spring-jdbc\5.3.5\spring-jdbc-5.3.5.jar;X:\repository\org\springframework\spring-tx\5.3.5\spring-tx-5.3.5.jar;X:\repository\org\mybatis\spring\boot\mybatis-spring-boot-autoconfigure\2.1.4\mybatis-spring-boot-autoconfigure-2.1.4.jar;X:\repository\org\mybatis\mybatis\3.5.6\mybatis-3.5.6.jar;X:\repository\org\mybatis\mybatis-spring\2.0.6\mybatis-spring-2.0.6.jar;X:\repository\mysql\mysql-connector-java\5.1.38\mysql-connector-java-5.1.38.jar;X:\repository\com\alibaba\druid\1.1.12\druid-1.1.12.jar;X:\repository\org\springframework\spring-core\5.3.5\spring-core-5.3.5.jar;X:\repository\org\springframework\spring-jcl\5.3.5\spring-jcl-5.3.5.jar;X:\repository\org\springframework\boot\spring-boot-starter-web\2.4.4\spring-boot-starter-web-2.4.4.jar;X:\repository\org\springframework\boot\spring-boot-starter-json\2.4.4\spring-boot-starter-json-2.4.4.jar;X:\repository\com\fasterxml\jackson\core\jackson-databind\2.11.4\jackson-databind-2.11.4.jar;X:\repository\com\fasterxml\jackson\core\jackson-annotations\2.11.4\jackson-annotations-2.11.4.jar;X:\repository\com\fasterxml\jackson\core\jackson-core\2.11.4\jackson-core-2.11.4.jar;X:\repository\com\fasterxml\jackson\datatype\jackson-datatype-jdk8\2.11.4\jackson-datatype-jdk8-2.11.4.jar;X:\repository\com\fasterxml\jackson\datatype\jackson-datatype-jsr310\2.11.4\jackson-datatype-jsr310-2.11.4.jar;X:\repository\com\fasterxml\jackson\module\jackson-module-parameter-names\2.11.4\jackson-module-parameter-names-2.11.4.jar;X:\repository\org\springframework\boot\spring-boot-starter-tomcat\2.4.4\spring-boot-starter-tomcat-2.4.4.jar;X:\repository\org\apache\tomcat\embed\tomcat-embed-core\9.0.44\tomcat-embed-core-9.0.44.jar;X:\repository\org\glassfish\jakarta.el\3.0.3\jakarta.el-3.0.3.jar;X:\repository\org\apache\tomcat\embed\tomcat-embed-websocket\9.0.44\tomcat-embed-websocket-9.0.44.jar;X:\repository\org\springframework\spring-web\5.3.5\spring-web-5.3.5.jar;X:\repository\org\springframework\spring-beans\5.3.5\spring-beans-5.3.5.jar;X:\repository\org\springframework\spring-webmvc\5.3.5\spring-webmvc-5.3.5.jar;X:\repository\org\springframework\spring-aop\5.3.5\spring-aop-5.3.5.jar;X:\repository\org\springframework\spring-context\5.3.5\spring-context-5.3.5.jar;X:\repository\org\springframework\spring-expression\5.3.5\spring-expression-5.3.5.jar com.bjsxt.mybatis_demo.MybatisDemoApplication

  .   ____          _            __ _ _

 /\\ / ___'_ __ _ _(_)_ __  __ _ \ \ \ \

( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \

 \\/  ___)| |_)| | | | | || (_| |  ) ) ) )

  '  |____| .__|_| |_|_| |_\__, | / / / /

 =========|_|==============|___/=/_/_/_/

 :: Spring Boot ::                (v2.4.4)

2021-04-15 17:44:16.007  INFO 11728 --- [           main] c.b.mybatis_demo.MybatisDemoApplication  : Starting MybatisDemoApplication using Java 11.0.6 on DESKTOP-1A2NPGT with PID 11728 (X:\Java学习\springboot_text\mybatis_demo\target\classes started by 95650 in X:\Java学习\springboot_text)

2021-04-15 17:44:16.010  INFO 11728 --- [           main] c.b.mybatis_demo.MybatisDemoApplication  : No active profile set, falling back to default profiles: default

2021-04-15 17:44:17.192  INFO 11728 --- [           main] o.s.b.w.embedded.tomcat.TomcatWebServer  : Tomcat initialized with port(s): 8080 (http)

2021-04-15 17:44:17.206  INFO 11728 --- [           main] o.apache.catalina.core.StandardService   : Starting service [Tomcat]

2021-04-15 17:44:17.206  INFO 11728 --- [           main] org.apache.catalina.core.StandardEngine  : Starting Servlet engine: [Apache Tomcat/9.0.44]

2021-04-15 17:44:17.209  INFO 11728 --- [           main] o.a.catalina.core.AprLifecycleListener   : Loaded Apache Tomcat Native library [1.2.23] using APR version [1.7.0].

2021-04-15 17:44:17.209  INFO 11728 --- [           main] o.a.catalina.core.AprLifecycleListener   : APR capabilities: IPv6 [true], sendfile [true], accept filters [false], random [true].

2021-04-15 17:44:17.210  INFO 11728 --- [           main] o.a.catalina.core.AprLifecycleListener   : APR/OpenSSL configuration: useAprConnector [false], useOpenSSL [true]

2021-04-15 17:44:17.216  INFO 11728 --- [           main] o.a.catalina.core.AprLifecycleListener   : OpenSSL successfully initialized [OpenSSL 1.1.1c  28 May 2019]

2021-04-15 17:44:17.348  INFO 11728 --- [           main] o.a.c.c.C.[Tomcat].[localhost].[/]       : Initializing Spring embedded WebApplicationContext

2021-04-15 17:44:17.352  INFO 11728 --- [           main] w.s.c.ServletWebServerApplicationContext : Root WebApplicationContext: initialization completed in 1284 ms

2021-04-15 17:44:17.412  WARN 11728 --- [           main] ConfigServletWebServerApplicationContext : Exception encountered during context initialization - cancelling refresh attempt: org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'usersServiceImpl': Unsatisfied dependency expressed through field 'usersMapper'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'usersMapper' defined in file [X:\Java学习\springboot_text\mybatis_demo\target\classes\com\bjsxt\mybatis_demo\mapper\UsersMapper.class]: Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required

2021-04-15 17:44:17.412  INFO 11728 --- [           main] o.apache.catalina.core.StandardService   : Stopping service [Tomcat]

2021-04-15 17:44:17.444  WARN 11728 --- [           main] o.a.c.loader.WebappClassLoaderBase       : The web application [ROOT] appears to have started a thread named [Abandoned connection cleanup thread] but has failed to stop it. This is very likely to create a memory leak. Stack trace of thread:

 java.base@11.0.6/java.lang.Object.wait(Native Method)

 java.base@11.0.6/java.lang.ref.ReferenceQueue.remove(ReferenceQueue.java:155)

 app//com.mysql.jdbc.AbandonedConnectionCleanupThread.run(AbandonedConnectionCleanupThread.java:43)

2021-04-15 17:44:17.459  INFO 11728 --- [           main] ConditionEvaluationReportLoggingListener : 

Error starting ApplicationContext. To display the conditions report re-run your application with 'debug' enabled.

2021-04-15 17:44:17.475 ERROR 11728 --- [           main] o.s.boot.SpringApplication               : Application run failed

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'usersServiceImpl': Unsatisfied dependency expressed through field 'usersMapper'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'usersMapper' defined in file [X:\Java学习\springboot_text\mybatis_demo\target\classes\com\bjsxt\mybatis_demo\mapper\UsersMapper.class]: Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required

at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.resolveFieldValue(AutowiredAnnotationBeanPostProcessor.java:660) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:640) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:119) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:399) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1413) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:601) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:524) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:944) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:918) ~[spring-context-5.3.5.jar:5.3.5]

at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:583) ~[spring-context-5.3.5.jar:5.3.5]

at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:144) ~[spring-boot-2.4.4.jar:2.4.4]

at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:769) ~[spring-boot-2.4.4.jar:2.4.4]

at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:761) ~[spring-boot-2.4.4.jar:2.4.4]

at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:426) ~[spring-boot-2.4.4.jar:2.4.4]

at org.springframework.boot.SpringApplication.run(SpringApplication.java:326) ~[spring-boot-2.4.4.jar:2.4.4]

at org.springframework.boot.SpringApplication.run(SpringApplication.java:1313) ~[spring-boot-2.4.4.jar:2.4.4]

at org.springframework.boot.SpringApplication.run(SpringApplication.java:1302) ~[spring-boot-2.4.4.jar:2.4.4]

at com.bjsxt.mybatis_demo.MybatisDemoApplication.main(MybatisDemoApplication.java:13) ~[classes/:na]

Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'usersMapper' defined in file [X:\Java学习\springboot_text\mybatis_demo\target\classes\com\bjsxt\mybatis_demo\mapper\UsersMapper.class]: Invocation of init method failed; nested exception is java.lang.IllegalArgumentException: Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1786) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:602) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:524) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:335) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:234) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:333) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:208) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.config.DependencyDescriptor.resolveCandidate(DependencyDescriptor.java:276) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1380) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1300) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.resolveFieldValue(AutowiredAnnotationBeanPostProcessor.java:657) ~[spring-beans-5.3.5.jar:5.3.5]

... 21 common frames omitted

Caused by: java.lang.IllegalArgumentException: Property 'sqlSessionFactory' or 'sqlSessionTemplate' are required

at org.springframework.util.Assert.notNull(Assert.java:201) ~[spring-core-5.3.5.jar:5.3.5]

at org.mybatis.spring.support.SqlSessionDaoSupport.checkDaoConfig(SqlSessionDaoSupport.java:122) ~[mybatis-spring-2.0.6.jar:2.0.6]

at org.mybatis.spring.mapper.MapperFactoryBean.checkDaoConfig(MapperFactoryBean.java:73) ~[mybatis-spring-2.0.6.jar:2.0.6]

at org.springframework.dao.support.DaoSupport.afterPropertiesSet(DaoSupport.java:44) ~[spring-tx-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.invokeInitMethods(AbstractAutowireCapableBeanFactory.java:1845) ~[spring-beans-5.3.5.jar:5.3.5]

at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.initializeBean(AbstractAutowireCapableBeanFactory.java:1782) ~[spring-beans-5.3.5.jar:5.3.5]

... 31 common frames omitted

Process finished with exit code 1

soft nofile 65536
hard nofile 65536

配置了还是报错

bootstrap check failure [1] of [2]: max file descriptors [4096] for elasticsearch process is too low, increase to at least [65535]
bootstrap check failure [2] of [2]: max number of threads [3802] for user [es] is too low, increase to at least [4096]

查了一下，重新配置了

* soft nofile 65536
* hard nofile 65536
es soft nproc 65536
es hard nproc 65536

package com.renyiyv;


import java.io.File;
import java.io.IOException;
import java.util.Date;

//测试文件类
public class TestFile {
    public static void main(String[] args) throws IOException {
        System.out.println(System.getProperty("user.dir"));
        File f=new File("d:/a.txt");//绝对路径
        f.createNewFile();//创建新的File

        File f2=new File("b.txt");//相对路径
        f2.createNewFile();

        System.out.println("File是否存在:"+f.exists());
        System.out.println("File是否是目录:"+f.isDirectory());
        System.out.println("File是否是文件:"+f.isFile());
        System.out.println("File最后的修改时间:"+new Date(f.lastModified()));
        System.out.println("File的大小:"+f.length());
        System.out.println("File的文件名:"+f.getName());
        System.out.println("File的目录路径"+f.getAbsolutePath());

        File f3=new File("d:电影/华语/大陆");
        //boolean flag=f3.mkdir();//目录结构中有一个不存在，则不会创建整个目录树
        //System.out.println(flag);//创建失败

        boolean flag=f3.mkdirs();
        System.out.println(flag);


    }
}

老师您好，根据代码，f3目录理论上应该在d盘下创建的才对，我这个为什么在项目文件夹里？

为什么我一到爆炸就弹这个，

if(explode == null){

    explode = new Explode(p.x,p.y);

}

explode.drawMyself(g);

这段代码照着打的

老师我出现下面情况怎么做

PS D:\gameshop> & "D:/python/Environment library/ENV/shop_env/Scripts/Activate.ps1"

& : 无法加载文件 D:\python\Environment library\ENV\shop_env\Scripts\Activate.ps1，因为在此系统上禁止运行脚本。有关详细信息，请参阅 https:/go.microsoft.com/fwlink/?LinkID=135170 中的 about_Execution_Policies。

所在位置 行:1 字符: 3

+ & "D:/python/Environment library/ENV/shop_env/Scripts/Activate.ps1"   

+   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~   

    + CategoryInfo          : SecurityError: (:) []，PSSecurityException

    + FullyQualifiedErrorId : UnauthorizedAccess

import sys
class AA():
    # 创建对象开辟内存时调用
    def __new__(cls, *args, **kwargs):
        print('开辟内存空间')
        return super(AA, cls).__new__(cls)

    # 初始化方法
    def __init__(self):
        print('创建对象at:%s' % hex(id(self)))

    # 对象被系统回收之前调用该方法
    def __del__(self):
        print('%s say bye bye' % hex(id(self)))
def test1(aaa):
    print('aaa')
    print('a的引用计数为：%d' % sys.getrefcount(a))

a = AA()
print('a的引用计数为：%d' % sys.getrefcount(a))
b = a
print('a的引用计数为：%d' % sys.getrefcount(a))
list1 = [a]
print('a的引用计数为：%d' % sys.getrefcount(a))
test1(a)
print('a的引用计数为：%d' % sys.getrefcount(a))
print('-'*50)
b = 100
print('a的引用计数为：%d' % sys.getrefcount(a))
list1.remove(a)
print('a的引用计数为：%d' % sys.getrefcount(a))
print('-'*20+'程序结束'+'-'*20)

老师，这个后面好几个引用a的，这里函数的执行顺序有点理不清了，麻烦老师讲解一下

最后的居中问题，是不是可以理解为让子元素脱离文档流，无视了border带来的影响，他眼里只有自己的父元素哈哈哈