org.apache.fop.fo.properties.FontStretchPropertyMaker Maven / Gradle / Ivy
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/* $Id: FontStretchPropertyMaker.java 1610839 2014-07-15 20:25:58Z vhennebert $ */
package org.apache.fop.fo.properties;
import org.apache.fop.fo.Constants;
import org.apache.fop.fo.FObj;
import org.apache.fop.fo.PropertyList;
import org.apache.fop.fo.expr.PropertyException;
/**
* This subclass of EnumProperty.Maker handles the special treatment of
* relative font stretch values described in 7.8.5.
*/
public class FontStretchPropertyMaker
extends EnumProperty.Maker implements Constants {
/* Ordered list of absolute font stretch properties so we can easily find the next /
* previous one */
private Property[] orderedFontStretchValues;
/**
* Create an enum property which can handle relative font stretches
* @param propId the font size property id.
*/
public FontStretchPropertyMaker(int propId) {
super(propId);
}
/**
* {@inheritDoc}
* Implements the parts of 7.8.5 relevant to relative font stretches
*/
public Property convertProperty(Property p,
PropertyList propertyList,
FObj fo) throws PropertyException {
// if it is a relative font stretch value get current parent value and step
// up or down accordingly
if (p.getEnum() == EN_NARROWER) {
return computeNextAbsoluteFontStretch(propertyList.getFromParent(this.getPropId()), -1);
} else if (p.getEnum() == EN_WIDER) {
return computeNextAbsoluteFontStretch(propertyList.getFromParent(this.getPropId()), 1);
}
return super.convertProperty(p, propertyList, fo);
}
/**
* Calculates the nearest absolute font stretch property to the given
* font stretch
* @param baseProperty the font stretch property as set on the parent fo
* @param direction should be -1 to get the next narrower value or +1 for the next wider value
*/
private Property computeNextAbsoluteFontStretch(Property baseProperty, int direction) {
// Create the table entries the first time around
// @todo is this thread safe, do we need to worry about this here?
if (orderedFontStretchValues == null) {
orderedFontStretchValues = new Property[] {
checkEnumValues("ultra-condensed"),
checkEnumValues("extra-condensed"),
checkEnumValues("condensed"),
checkEnumValues("semi-condensed"),
checkEnumValues("normal"),
checkEnumValues("semi-expanded"),
checkEnumValues("expanded"),
checkEnumValues("extra-expanded"),
checkEnumValues("ultra-expanded")
};
}
int baseValue = baseProperty.getEnum();
for (int i = 0; i < orderedFontStretchValues.length; i++) {
if (baseValue == orderedFontStretchValues[i].getEnum()) {
// increment/decrement the index and make sure its within the array bounds
i = Math.min(Math.max(0, i + direction), orderedFontStretchValues.length - 1);
return orderedFontStretchValues[i];
}
}
// return the normal value
return orderedFontStretchValues[4];
}
}