void checkInsert() {
		Object temp[] = new Object[18];
		int p=0;
		if (textField_6.getText() == "") {
               JTextField ISBN = new JTextField();
               temp[p]="ISBN:";
               p++;
               temp[p]=ISBN;
               p++;
		}
		if (textField_7.getText() == "") {
            JTextField title = new JTextField();
            temp[p]="Title:";
            p++;
            temp[p]=title;
            p++;
		}
		if (textField_8.getText() == "") {
            JTextField Publisher = new JTextField();
            temp[p]="Publisher:";
            p++;
            temp[p]=Publisher;
            p++;

		}
		if (textField_8.getText() == "") {
            JTextField year = new JTextField();
            temp[p]="Year:";
            p++;
            temp[p]=year;
            p++;
		}
		if (textField_9.getText() == "") {
            JTextField ISBN = new JTextField();
            temp[p]="ISBN:";
            p++;
            temp[p]=ISBN;
            p++;
		}
		if (textField_10.getText() == "") {
            JTextField price = new JTextField();
            temp[p]="Price:";
            p++;
            temp[p]=price;
            p++;
		}
		if (textField_11.getText() == "") {
            JTextField catg = new JTextField();
            temp[p]="Category:";
            p++;
            temp[p]=catg;
            p++;
		}
		if (textField_12.getText() == "") {
            JTextField copy = new JTextField();
            temp[p]="Copies:";
            p++;
            temp[p]=copy;
            p++;
		}
		if (textField_5.getText() == "") {
            JTextField threshold = new JTextField();
            temp[p]="Theshold:";
            p++;
            temp[p]=threshold;
            p++;
		}
		Object msg[] = new Object[p];
		for (int i = 0; i < msg.length; i++) {
			msg[i]=temp[i];
		}

		int option = JOptionPane.showConfirmDialog(null, msg,
				"Publisher", JOptionPane.OK_CANCEL_OPTION);
		if (option == JOptionPane.OK_OPTION) {

		}
	}