线程报错Exception in thread "main" java.lang.NoClassDefFoundError: mythread (wrong name: MyThread)

Question

ideal报错：
"C:\Program Files (x86)\Java\jdk1.8.0_73\bin\java.exe" "-javaagent:C:\Program Files\JetBrains\IntelliJ IDEA 2020.3.1\lib\idea_rt.jar=7139:C:\Program Files\JetBrains\IntelliJ IDEA 2020.3.1\bin" -Dfile.encoding=UTF-8 -classpath "C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\charsets.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\deploy.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\access-bridge-32.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\cldrdata.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\dnsns.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\jaccess.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\jfxrt.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\localedata.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\nashorn.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\sunec.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\sunjce_provider.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\sunmscapi.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\sunpkcs11.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\ext\zipfs.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\javaws.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\jce.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\jfr.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\jfxswt.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\jsse.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\management-agent.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\plugin.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\resources.jar;C:\Program Files (x86)\Java\jdk1.8.0_73\jre\lib\rt.jar;C:\Users\balabala\IdeaProjects\untitled\c3-csq\out\production\week4" Demo01ChangeThreadname
Exception in thread "main" java.lang.NoClassDefFoundError: MyThread (wrong name: Mythread)
at java.lang.ClassLoader.defineClass1(Native Method)
at java.lang.ClassLoader.defineClass(ClassLoader.java:760)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:467)
at java.net.URLClassLoader.access$100(URLClassLoader.java:73)
at java.net.URLClassLoader$1.run(URLClassLoader.java:368)
at java.net.URLClassLoader$1.run(URLClassLoader.java:362)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:361)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at Demo01ChangeThreadname.main(Demo01ChangeThreadname.java:10)

进程已结束，退出代码为 1

我的代码：
class mythread extends Thread{
    @Override
    public void run() {
        //获取线程名称
        System.out.println(Thread.currentThread().getName());
    }
}
public class Demo01ChangeThreadname {
    public static void main(String[] args) {
        mythread mt = new mythread();
        mt.setName("小帅");
        mt.start();
    }
}

Answer 1

把类名Mythread改为MyThread。T改为大写。