thisClass =3

package ;

import java.io.File;
import java.io.IOException;

import <mymainclass>;

public class thisClass {
    static <mymainclass> plugin;
    public thisClass(<mymainclass> plugin) {
        thisClass.plugin = plugin;
    }

    private static File thisFile = null;

    public static void createFile() {
        if (thisFile == null) {
            File thisFile = new File(plugin.getDataFolder(), "file.txt");
            try {
                thisFile.createNewFile();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}