I downloaded the apache FTPServer file and ran through CMD the ftpd.bat from the bin folder (I am a windows user), but it gives me an error which at this point I no longer know how to solve.
https://i.stack.imgur.com/jgGDd.png
I’m still a fairly new programmer.
I did research on the issues in the image but couldn’t get to much.
I ask this question due to the moment I use the Apache FTPServer libraries, they compile well for me but it gives me an error when the program is executed and I think it is due to the above, although I could be wrong.
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/mina/filter/executor/OrderedThreadPoolExecutor
at org.apache.ftpserver.FtpServerFactory.<init>(FtpServerFactory.java:49)
at prueba_server_ftp.server.main(server.java:21)
Caused by: java.lang.ClassNotFoundException: org.apache.mina.filter.executor.OrderedThreadPoolExecutor
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:641)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:188)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
... 2 more
This error occurs when i try to initialize declaring any variable of FTPServer as FtpServerFactory or ListenerFactory;
>Solution :
This error in the screenshot means that the port the application is trying to use (port 21) is already in use by another process. Maybe you have the server running already or some other process is using the port.
You can download ‘CurrPorts` from https://www.nirsoft.net/utils/cports.html
and use it to see which process is using the port and kill it before running the app again.