执行结果：

老师帮忙看一下图片里的问题，凑够20个字才可以提交问题

老师出现这个情况应该怎么解决呢，是下载的版本太高了吗，出现不匹配的问题

老师这个是怎么回事呀，为什么说不允许出现noNameSpaceSchemaLocation这个属性呀，而且我在idea中打这个属性的名字的时候idea也没有出现提示

看了7樓小夥伴和我一樣的問題，他的在g盤，我有嘗試做，可是不對呀

在server中输出编码正常

但是在tomcat catalina log 中却出现乱码,这个应该怎么做

老师帮忙看下哪里出错

"C:\Program Files\Java\jdk1.8.0_231\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2020.1\lib\idea_rt.jar=58553:C:\Program Files\JetBrains\IntelliJ IDEA 2020.1\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files\Java\jdk1.8.0_231\jre\lib\charsets.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\deploy.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\access-bridge-64.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\cldrdata.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\dnsns.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\jaccess.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\jfxrt.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\localedata.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\nashorn.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\sunec.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\sunjce_provider.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\sunmscapi.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\sunpkcs11.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\ext\zipfs.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\javaws.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\jce.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\jfr.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\jfxswt.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\jsse.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\management-agent.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\plugin.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\resources.jar;C:\Program Files\Java\jdk1.8.0_231\jre\lib\rt.jar;C:\JAVA_workspace_idea\Mybatisdemo\out\production\Mybatisdemo;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\asm-7.1.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\cglib-3.3.0.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\ognl-3.2.14.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\log4j-1.2.17.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\mybatis-3.5.5.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\log4j-api-2.13.3.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\slf4j-api-1.7.30.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\log4j-core-2.13.3.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\commons-logging-1.2.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\javassist-3.27.0-GA.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\slf4j-log4j12-1.7.30.jar;C:\Users\j1781\Desktop\百战程序员\jar包环境\Mybatis\lib\mysql-connector-java-5.1.48.jar" com.bjsxt.test.Test

log4j:WARN No appenders could be found for logger (org.apache.ibatis.logging.LogFactory).

log4j:WARN Please initialize the log4j system properly.

log4j:WARN See http://logging.apache.org/log4j/1.2/faq.html#noconfig for more info.

Exception in thread "main" org.apache.ibatis.exceptions.PersistenceException: 

### Error building SqlSession.

### The error may exist in SQL Mapper Configuration

### Cause: org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.datasource.DataSourceException: Unknown DataSource property: mysqlDriver

at org.apache.ibatis.exceptions.ExceptionFactory.wrapException(ExceptionFactory.java:30)

at org.apache.ibatis.session.SqlSessionFactoryBuilder.build(SqlSessionFactoryBuilder.java:80)

at org.apache.ibatis.session.SqlSessionFactoryBuilder.build(SqlSessionFactoryBuilder.java:64)

at com.bjsxt.dao.impl.UsersDaoImpl.selectUsersAll(UsersDaoImpl.java:21)

at com.bjsxt.test.Test.main(Test.java:12)

Caused by: org.apache.ibatis.builder.BuilderException: Error parsing SQL Mapper Configuration. Cause: org.apache.ibatis.datasource.DataSourceException: Unknown DataSource property: mysqlDriver

at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:122)

at org.apache.ibatis.builder.xml.XMLConfigBuilder.parse(XMLConfigBuilder.java:99)

at org.apache.ibatis.session.SqlSessionFactoryBuilder.build(SqlSessionFactoryBuilder.java:78)

... 3 more

Caused by: org.apache.ibatis.datasource.DataSourceException: Unknown DataSource property: mysqlDriver

at org.apache.ibatis.datasource.unpooled.UnpooledDataSourceFactory.setProperties(UnpooledDataSourceFactory.java:55)

at org.apache.ibatis.builder.xml.XMLConfigBuilder.dataSourceElement(XMLConfigBuilder.java:329)

at org.apache.ibatis.builder.xml.XMLConfigBuilder.environmentsElement(XMLConfigBuilder.java:283)

at org.apache.ibatis.builder.xml.XMLConfigBuilder.parseConfiguration(XMLConfigBuilder.java:117)

... 5 more

Process finished with exit code 1

package com.yu.test03;

import java.io.*;

public class TestException02 {
    public static void main(String[] args){
        InputStream  a = null;
        try {
            a = new FileInputStream("D://c");
            System.out.println("代码不执行");
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }finally{
            try {
                a.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        System.out.println("TestException02.main");
    }
}

老师，如果try捕获异常后，最后一句输出代码可以执行吗

这行代码是什么，之前好像没有诶

也不运行 窗口显示一会就直接闪退了 您能帮我远程看看吗

在安装nginx的时候错了这个错误，网上没找到一样的问题，有类似的但是方法用起来没有用

老师  那个无参构造器有什么具体用法

老师 ，安装pyinstaller出现这个问题，安装不上，是怎么回事？

EnemyTank(Tank）：

要继承父类咯

老师这个this指的当前对象，是哪个当前对象

老师为什么以前我做项目的时候也在IDEA里面添加过DTD配置文件，等再开一个新的项目时generatorConfig.xml文件又爆红呢？老师不是说添加一次就好了吗？有没有什么办法一劳永逸呀