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pdfHTML is an iText 7 add-on that lets you to parse (X)HTML snippets and the associated CSS and converts
them to PDF.
/*
This file is part of the iText (R) project.
Copyright (c) 1998-2017 iText Group NV
Authors: Bruno Lowagie, Paulo Soares, et al.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU Affero General Public License version 3
as published by the Free Software Foundation with the addition of the
following permission added to Section 15 as permitted in Section 7(a):
FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
OF THIRD PARTY RIGHTS
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 or write to
the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
Boston, MA, 02110-1301 USA, or download the license from the following URL:
http://itextpdf.com/terms-of-use/
The interactive user interfaces in modified source and object code versions
of this program must display Appropriate Legal Notices, as required under
Section 5 of the GNU Affero General Public License.
In accordance with Section 7(b) of the GNU Affero General Public License,
a covered work must retain the producer line in every PDF that is created
or manipulated using iText.
You can be released from the requirements of the license by purchasing
a commercial license. Buying such a license is mandatory as soon as you
develop commercial activities involving the iText software without
disclosing the source code of your own applications.
These activities include: offering paid services to customers as an ASP,
serving PDFs on the fly in a web application, shipping iText with a closed
source product.
For more information, please contact iText Software Corp. at this
address: [email protected]
*/
package com.itextpdf.html2pdf.attach.util;
import com.itextpdf.io.util.NumberUtil;
import com.itextpdf.layout.border.Border;
import com.itextpdf.layout.element.IElement;
import com.itextpdf.layout.element.Text;
import com.itextpdf.layout.layout.LayoutPosition;
import com.itextpdf.layout.property.FloatPropertyValue;
import com.itextpdf.layout.property.Property;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
/**
* Utility class to trim content.
*/
public final class TrimUtil {
private static final Set EM_SPACES = new HashSet<>();
static {
EM_SPACES.add((char) 0x2002);
EM_SPACES.add((char) 0x2003);
EM_SPACES.add((char) 0x2009);
}
/**
* Creates a new {@link TrimUtil} instance.
*/
private TrimUtil() {
}
/**
* Trim leaf elements, and sanitize.
*
* @param leafElements the leaf elements
* @return the trimmed and sanitized list
*/
static List trimLeafElementsAndSanitize(List leafElements) {
ArrayList waitingLeaves = new ArrayList(leafElements);
trimSubList(waitingLeaves, 0, waitingLeaves.size(), false);
trimSubList(waitingLeaves, 0, waitingLeaves.size(), true);
int pos = 0;
while (pos < waitingLeaves.size() - 1) {
if (waitingLeaves.get(pos) instanceof Text) {
Text first = (Text) waitingLeaves.get(pos);
if (isElementFloating(first)) {
trimTextElement(first, false);
trimTextElement(first, true);
} else {
int firstEnd = getIndexAfterLastNonSpace(first);
if (firstEnd < first.getText().length()) {
trimSubList(waitingLeaves, pos + 1, waitingLeaves.size(), false);
first.setText(first.getText().substring(0, firstEnd + 1));
}
}
}
pos++;
}
return waitingLeaves;
}
/**
* Checks if a character is white space value that doesn't cause a newline.
*
* @param ch the character
* @return true, if the character is a white space character, but no newline
*/
static boolean isNonLineBreakSpace(char ch) {
return isNonEmSpace(ch) && ch != '\n';
}
/**
* Checks if a character is white space value that is not em, en or similar special whitespace character.
*
* @param ch the character
* @return true, if the character is a white space character, but no em, en or similar
*/
static boolean isNonEmSpace(char ch) {
return Character.isWhitespace(ch) && !EM_SPACES.contains(ch);
}
/**
* Trims a sub list of leaf elements.
*
* @param list the list of leaf elements
* @param begin the index where to begin
* @param end the index where to end
* @param last indicates where to start, if true, we start at the end
*/
private static void trimSubList(ArrayList list, int begin, int end, boolean last) {
while (end > begin) {
int pos = last ? end - 1 : begin;
IElement leaf = list.get(pos);
if (isElementFloating(leaf)) {
if (last) { --end; }
else { ++begin; }
continue;
}
if (leaf instanceof Text) {
Text text = (Text) leaf;
trimTextElement(text, last);
if (text.getText().length() == 0) {
if (hasZeroWidth(text)) {
list.remove(pos);
}
end--;
continue;
}
}
break;
}
}
/**
* Trims a text element.
*
* @param text the text element
* @param last indicates where to start, if true, we start at the end
*/
private static void trimTextElement(Text text, boolean last) {
int begin = last ? 0 : getIndexOfFirstNonSpace(text);
int end = last ? getIndexAfterLastNonSpace(text) : text.getText().length();
text.setText(text.getText().substring(begin, end));
}
/**
* Gets the index of first character that isn't white space in some text.
* Note: newline characters aren't counted as white space characters.
*
* @param text the text
* @return the index of first character that isn't white space
*/
private static int getIndexOfFirstNonSpace(Text text) {
int pos = 0;
while (pos < text.getText().length() && isNonLineBreakSpace(text.getText().charAt(pos))) {
pos++;
}
return pos;
}
/**
* Gets the index of last character following a character that isn't white space in some text.
* Note: newline characters aren't counted as white space characters.
*
* @param text the text
* @return the index following the last character that isn't white space
*/
private static int getIndexAfterLastNonSpace(Text text) {
int pos = text.getText().length();
while (pos > 0 && isNonLineBreakSpace(text.getText().charAt(pos - 1))) {
pos--;
}
return pos;
}
private static boolean isElementFloating(IElement leafElement) {
FloatPropertyValue floatPropertyValue = leafElement.getProperty(Property.FLOAT);
Integer position = leafElement.getProperty(Property.POSITION);
return (position == null || position != LayoutPosition.ABSOLUTE) && floatPropertyValue != null && !floatPropertyValue.equals(FloatPropertyValue.NONE);
}
private static boolean hasZeroWidth(IElement leafElement) {
return
(null == leafElement.getProperty(Property.BORDER_RIGHT) || 0 == ((Border) leafElement.getProperty(Property.BORDER_RIGHT)).getWidth()) &&
(null == leafElement.getProperty(Property.BORDER_LEFT) || 0 == ((Border) leafElement.getProperty(Property.BORDER_LEFT)).getWidth()) &&
(null == leafElement.