org.jfree.xml.ParserUtil Maven / Gradle / Ivy
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/* ========================================================================
* JCommon : a free general purpose class library for the Java(tm) platform
* ========================================================================
*
* (C) Copyright 2000-2005, by Object Refinery Limited and Contributors.
*
* Project Info: http://www.jfree.org/jcommon/index.html
*
* 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 library 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.
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
* USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* ---------------
* ParserUtil.java
* ---------------
* (C)opyright 2002-2005, by Thomas Morgner and Contributors.
*
* Original Author: Thomas Morgner ([email protected]);
* Contributor(s): David Gilbert (for Object Refinery Limited);
*
* $Id: ParserUtil.java,v 1.3 2005/10/18 13:25:44 mungady Exp $
*
* Changes
* -------
* 21-May-2002 : Contains utility functions to make parsing easier.
* 10-Dec-2002 : Fixed issues reported by Checkstyle (DG);
* 29-Apr-2003 : Distilled from the JFreeReport project and moved into JCommon;
* 23-Sep-2003 : Minor Javadoc updates (DG);
*
*/
package org.jfree.xml;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Stroke;
import java.awt.geom.Rectangle2D;
import java.lang.reflect.Field;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
/**
* Basic helper functions to ease up the process of parsing.
*
* @author Thomas Morgner
*/
public class ParserUtil {
/**
* Parses the string text into an int. If text is null or does not
* contain a parsable value, the message given in message is used to
* throw a SAXException.
*
* @param text the text to parse.
* @param message the error message if parsing fails.
*
* @return the int value.
*
* @throws SAXException if there is a problem with the parsing.
*/
public static int parseInt(final String text, final String message) throws SAXException {
if (text == null) {
throw new SAXException(message);
}
try {
return Integer.parseInt(text);
}
catch (NumberFormatException nfe) {
throw new SAXException("NumberFormatError: " + message);
}
}
/**
* Parses an integer.
*
* @param text the text to parse.
* @param defaultVal the default value.
*
* @return the integer.
*/
public static int parseInt(final String text, final int defaultVal) {
if (text == null) {
return defaultVal;
}
try {
return Integer.parseInt(text);
}
catch (NumberFormatException nfe) {
return defaultVal;
}
}
/**
* Parses the string text into an float. If text is null or does not
* contain a parsable value, the message given in message is used to
* throw a SAXException.
*
* @param text the text to parse.
* @param message the error message if parsing fails.
*
* @return the float value.
*
* @throws SAXException if there is a problem with the parsing.
*/
public static float parseFloat(final String text, final String message) throws SAXException {
if (text == null) {
throw new SAXException(message);
}
try {
return Float.parseFloat(text);
}
catch (NumberFormatException nfe) {
throw new SAXException("NumberFormatError: " + message);
}
}
/**
* Parses the string text into an float. If text is null or does not
* contain a parsable value, the message given in message is used to
* throw a SAXException.
*
* @param text the text to parse.
* @param defaultVal the defaultValue returned if parsing fails.
*
* @return the float value.
*/
public static float parseFloat(final String text, final float defaultVal) {
if (text == null) {
return defaultVal;
}
try {
return Float.parseFloat(text);
}
catch (NumberFormatException nfe) {
return defaultVal;
}
}
/**
* Parses a boolean. If the string text contains the value of "true", the
* true value is returned, else false is returned.
*
* @param text the text to parse.
* @param defaultVal the default value.
*
* @return a boolean.
*/
public static boolean parseBoolean(final String text, final boolean defaultVal) {
if (text == null) {
return defaultVal;
}
return text.equalsIgnoreCase("true");
}
/**
* Parses a string. If the text is null, defaultval is returned.
*
* @param text the text to parse.
* @param defaultVal the default value.
*
* @return a string.
*/
public static String parseString(final String text, final String defaultVal) {
if (text == null) {
return defaultVal;
}
return text;
}
/**
* Creates a basic stroke given the width contained as float in the given string.
* If the string could not be parsed into a float, a basic stroke with the width of
* 1 is returned.
*
* @param weight a string containing a number (the stroke weight).
*
* @return the stroke.
*/
public static Stroke parseStroke(final String weight) {
try {
if (weight != null) {
final Float w = new Float(weight);
return new BasicStroke(w.floatValue());
}
}
catch (NumberFormatException nfe) {
//Log.warn("Invalid weight for stroke", nfe);
}
return new BasicStroke(1);
}
/**
* Parses a color entry. If the entry is in hexadecimal or ocal notation, the color is
* created using Color.decode(). If the string denotes a constant name of on of the color
* constants defined in java.awt.Color, this constant is used.
*
* As fallback the color black is returned if no color can be parsed.
*
* @param color the color (as a string).
*
* @return the paint.
*/
public static Color parseColor(final String color) {
return parseColor(color, Color.black);
}
/**
* Parses a color entry. If the entry is in hexadecimal or octal notation, the color is
* created using Color.decode(). If the string denotes a constant name of one of the color
* constants defined in java.awt.Color, this constant is used.
*
* As fallback the supplied default value is returned if no color can be parsed.
*
* @param color the color (as a string).
* @param defaultValue the default value (returned if no color can be parsed).
*
* @return the paint.
*/
public static Color parseColor(final String color, final Color defaultValue) {
if (color == null) {
return defaultValue;
}
try {
// get color by hex or octal value
return Color.decode(color);
}
catch (NumberFormatException nfe) {
// if we can't decode lets try to get it by name
try {
// try to get a color by name using reflection
// black is used for an instance and not for the color itselfs
final Field f = Color.class.getField(color);
return (Color) f.get(null);
}
catch (Exception ce) {
//Log.warn("No such Color : " + color);
// if we can't get any color return black
return defaultValue;
}
}
}
/**
* Parses a position of an element. If a relative postion is given, the returnvalue
* is a negative number between 0 and -100.
*
* @param value the value.
* @param exceptionMessage the exception message.
*
* @return the float value.
*
* @throws SAXException if there is a problem parsing the string.
*/
public static float parseRelativeFloat(final String value, final String exceptionMessage)
throws SAXException {
if (value == null) {
throw new SAXException(exceptionMessage);
}
final String tvalue = value.trim();
if (tvalue.endsWith("%")) {
final String number = tvalue.substring(0, tvalue.indexOf("%"));
final float f = parseFloat(number, exceptionMessage) * -1.0f;
return f;
}
else {
return parseFloat(tvalue, exceptionMessage);
}
}
/**
* Parses an element position. The position is stored in the attributes "x", "y", "width" and
* "height". The attributes are allowed to have relative notion.
*
* @param atts the attributes.
*
* @return the element position.
*
* @throws SAXException if there is a problem getting the element position.
*/
public static Rectangle2D getElementPosition(final Attributes atts) throws SAXException {
final float x = ParserUtil.parseRelativeFloat(atts.getValue("x"),
"Element x not specified");
final float y = ParserUtil.parseRelativeFloat(atts.getValue("y"),
"Element y not specified");
final float w = ParserUtil.parseRelativeFloat(atts.getValue("width"),
"Element width not specified");
final float h = ParserUtil.parseRelativeFloat(atts.getValue("height"),
"Element height not specified");
final Rectangle2D.Float retval = new Rectangle2D.Float(x, y, w, h);
return retval;
}
}