If you are using a commandline in a console window, you need to be in the correct directory relative to the .class file and use the java command with the classname. If the class is in a package it is more complicated.
For a class not in a package, change to the folder with the .class file and enter:
Also enter the dir command to show what is in the folder.
To copy the contents of the command prompt window:
Click on Icon in upper left corner
Select 'Select All' - The selection will show
Click in upper left again
Select Edit and click 'Copy'
For Each ctrl As Control In Me.Controls("pnlMainPanel").Controls
If ctrl.GetType Is GetType(System.Windows.Forms.Panel) Then
For Each subCtrl As Control In ctrl.Controls
If subCtrl.GetType Is GetType(System.Windows.Forms.TextBox) Then
If subCtrl.GetType Is ...