package TreeJuxtaposer;import java.io.File;import javax.swing.filechooser.*;public class NexusFilter extends FileFilter {	public NexusFilter(){}        public boolean accept(File f) {        if (f.isDirectory()) {            return true;     	}        String extension = Utils.getExtension(f);		if (extension != null &&		        ( extension.endsWith(Utils.nexus) || extension.endsWith(Utils.tre)))         	return true;	            return false;    }        // The description of this filter    public String getDescription() {        return Utils.nexus_file_description;    }}