IntegerField.java

/**
 * VStar: a statistical analysis tool for variable star data.
 * Copyright (C) 2010  AAVSO (http://www.aavso.org/)
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>. 
 */
package org.aavso.tools.vstar.ui.dialog;

import java.text.NumberFormat;

import org.aavso.tools.vstar.util.locale.NumberParser;
import org.aavso.tools.vstar.vela.VeLaEvalError;
import org.aavso.tools.vstar.vela.VeLaParseError;

/**
 * This class encapsulates the name, range, and value of an integer text
 * field along with a GUI textField and methods to operate upon it.
 */
public class IntegerField extends NumberFieldBase<Integer> {

	private final static NumberFormat NUM_FORMAT = NumberFormat.getIntegerInstance();

	/**
	 * Constructor
	 * 
	 * @param name    The name of the textField.
	 * @param min     The value that the entered value must be greater than (may be
	 *                null).
	 * @param max     The value that the entered value must be less than (may be
	 *                null).
	 * @param initial The initial value.
	 */
	public IntegerField(String name, Integer min, Integer max, Integer initial) {
		super(NUM_FORMAT, name, min, max, initial);
	}

	/**
	 * Get the integer value from the text field, if possible, otherwise return null
	 * if no valid number is present in the textField.
	 * 
	 * @return The integer value or null.
	 */
	public Integer getValue() {
		Integer value = null;

		try {
			value = (int) NumberParser.parseInteger(textField.getText());
			
			// In the previous realization, null is assigned to the value if value < min.
			// Then in the next 'if' the null value is compared with max, this leads to Null Pointer Exception.
			
			if (min != null && value < min) {
				return null;
			}

			if (max != null && value > max) {
				return null;
			}
		} catch (NumberFormatException e) {
			// Nothing to do; return null.
		} catch (VeLaParseError e) { // #PMAK#
			// Nothing to do; return null.
		} catch (VeLaEvalError e) { // #PMAK#
			// Nothing to do; return null.
		}

		return value;
	}

	@Override
	public void setValue(Integer value) {
		textField.setText(value == null ? "" : value.toString());
	}
}