Utils.java

import java.io.File;
import javax.swing.ImageIcon;

/* Utils.java is a 1.4 example used by FileChooserDemo2.java. */
public class Utils {
    public final static String hs = "hs";
    public final static String sum = "sum";
    public final static String formula = "for";
    public final static String ind = "ind";

    public static String getExtension(File f) {
        String ext = null;
        String s = f.getName();
        int i = s.lastIndexOf('.');

        if (i > 0 &&  i < s.length() - 1) {
            ext = s.substring(i+1).toLowerCase();
        }
        return ext;
    }

    protected static ImageIcon createImageIcon(String path) {
        java.net.URL imgURL = Utils.class.getResource(path);
        if (imgURL != null) {
            return new ImageIcon(imgURL);
        } else {
            System.err.println("Couldn't find file: " + path);
            return null;
        }
    }
}