jcckit.graphic.Anchor Maven / Gradle / Ivy
/*
* Copyright 2003-2004, Franz-Josef Elmer, All rights reserved
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as published by
* the Free Software Foundation; either version 2.1 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 Lesser General Public License for more details
* (http://www.gnu.org/copyleft/lesser.html).
*
* You should have received a copy of the GNU Lesser General Public License
* along with this library; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
package jcckit.graphic;
import jcckit.util.ConfigParameters;
import jcckit.util.FactoryException;
/**
* Anchor of a graphical element. There exist only the three
* instances {@link #LEFT_BOTTOM}, {@link #CENTER}, and
* {@link #RIGHT_TOP}.
*
* The anchor factor can be used in a position formular. Its value
* for the three instances reads:
*
*
*
* Instance Factor LEFT_BOTTOM 0 CENTER 1 RIGHT_TOP 2
*
*
* @author Franz-Josef Elmer
*/
public class Anchor {
/** Anchor constant. */
public static final Anchor LEFT_BOTTOM = new Anchor(0),
CENTER = new Anchor(1),
RIGHT_TOP = new Anchor(2);
private static final String LEFT_VALUE = "left",
RIGHT_VALUE = "right",
CENTER_VALUE = "center",
TOP_VALUE = "top",
BOTTOM_VALUE = "bottom";
/**
* Returns form the specified configuration parameters the
* horizontal anchor defined by the specified key or the
* specified default value.
* @param config Configuration parameters.
* @param key The key of the anchor. null is not allowed.
* @param defaultValue The default value.
* @return one of the three instances of Anchor.
* @throws FactoryException if the value of key is
* neither left, center,
* nor right.
* Note, that {@link FactoryException#getClassName()}
* returns the invalid value.
*/
public static Anchor getHorizontalAnchor(ConfigParameters config, String key,
Anchor defaultValue) {
Anchor result = defaultValue;
String anchor = config.get(key, null);
if (anchor != null) {
if (anchor.equals(LEFT_VALUE)) {
result = Anchor.LEFT_BOTTOM;
} else if (anchor.equals(CENTER_VALUE)) {
result = Anchor.CENTER;
} else if (anchor.equals(RIGHT_VALUE)) {
result = Anchor.RIGHT_TOP;
} else {
throw new FactoryException(config, key, "Invalid horizontal anchor.");
}
}
return result;
}
/**
* Returns form the specified configuration parameters the
* vertical anchor defined by the specified key or the
* specified default value.
* @param config Configuration parameters.
* @param key The key of the anchor. null is not allowed.
* @param defaultValue The default value.
* @return one of the three instances of Anchor.
* @throws FactoryException if the value of key is
* neither top, center,
* nor bottom.
* Note, that {@link FactoryException#getClassName()}
* returns the invalid value.
*/
public static Anchor getVerticalAnchor(ConfigParameters config, String key,
Anchor defaultValue) {
Anchor result = defaultValue;
String anchor = config.get(key, null);
if (anchor != null) {
if (anchor.equals(BOTTOM_VALUE)) {
result = Anchor.LEFT_BOTTOM;
} else if (anchor.equals(CENTER_VALUE)) {
result = Anchor.CENTER;
} else if (anchor.equals(TOP_VALUE)) {
result = Anchor.RIGHT_TOP;
} else {
throw new FactoryException(config, key, "Invalid vertcal anchor.");
}
}
return result;
}
private final int _factor;
private Anchor(int factor) {
_factor = factor;
}
/** Returns the factor. */
public int getFactor() {
return _factor;
}
}