Complete source code below will show you how to determine a pathname is a pathname for drive or not.
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COMPLETE SOURCE CODE FOR : PathnameIsDrive.java
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import javax.swing.JOptionPane;
import javax.swing.filechooser.FileSystemView;
import java.io.File;
public class PathnameIsDrive
{
 public static void main(String[]args)
 {
  //Create file instance from pathname
  //Try change to pathname that match any drive in your computer
  //For example C:\\ for C drive.
  File myFile=new File("C:\\");
  
  //Check whether the given pathname is drive or not
  if(FileSystemView.getFileSystemView().isDrive(myFile))
  {
   System.out.println("This is a drive");
  }
  else
  {
   System.out.println("This is not a drive");
  }
 }
}
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JUST COMPILE AND EXECUTE IT
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