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svg is a module for iText7 that allows you to integrate SVG images in your PDF creation and manipulation process
/*
This file is part of the iText (R) project.
Copyright (c) 1998-2018 iText Group NV
Authors: iText Software.
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.svg.processors.impl;
import com.itextpdf.styledxmlparser.css.ICssResolver;
import com.itextpdf.styledxmlparser.node.IElementNode;
import com.itextpdf.styledxmlparser.node.INode;
import com.itextpdf.styledxmlparser.node.ITextNode;
import com.itextpdf.svg.SvgConstants;
import com.itextpdf.svg.css.SvgCssContext;
import com.itextpdf.svg.css.impl.SvgStyleResolver;
import com.itextpdf.svg.exceptions.SvgLogMessageConstant;
import com.itextpdf.svg.exceptions.SvgProcessingException;
import com.itextpdf.svg.processors.ISvgConverterProperties;
import com.itextpdf.svg.processors.ISvgProcessor;
import com.itextpdf.svg.processors.ISvgProcessorResult;
import com.itextpdf.svg.processors.impl.font.SvgFontProcessor;
import com.itextpdf.svg.renderers.IBranchSvgNodeRenderer;
import com.itextpdf.svg.renderers.ISvgNodeRenderer;
import com.itextpdf.svg.renderers.factories.ISvgNodeRendererFactory;
import com.itextpdf.svg.renderers.impl.NoDrawOperationSvgNodeRenderer;
import com.itextpdf.svg.renderers.impl.TextSvgNodeRenderer;
import com.itextpdf.svg.utils.SvgTextUtil;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.Map;
/**
* Default implementation of {@link ISvgProcessor}.
* This implementation traverses the {@link INode} tree depth-first,
* using a stack to recreate a tree of {@link ISvgNodeRenderer} with the same structure.
*/
public class DefaultSvgProcessor implements ISvgProcessor {
private ProcessorState processorState;
private ICssResolver cssResolver;
private ISvgNodeRendererFactory rendererFactory;
private Map namedObjects;
private SvgCssContext cssContext;
private SvgProcessorContext context;
/**
* Instantiates a DefaultSvgProcessor object.
*/
public DefaultSvgProcessor() {
}
@Override
public ISvgProcessorResult process(INode root, ISvgConverterProperties converterProps) throws SvgProcessingException {
if (root == null) {
throw new SvgProcessingException(SvgLogMessageConstant.INODEROOTISNULL);
}
if (converterProps == null) {
converterProps = new SvgConverterProperties();
}
//Setup processorState
performSetup(root, converterProps);
//Find root
IElementNode svgRoot = findFirstElement(root, SvgConstants.Tags.SVG);
if (svgRoot != null) {
//Iterate over children
executeDepthFirstTraversal(svgRoot);
ISvgNodeRenderer rootSvgRenderer = createResultAndClean();
return new SvgProcessorResult(namedObjects, rootSvgRenderer,
context.getFontProvider(), context.getTempFonts());
} else {
throw new SvgProcessingException(SvgLogMessageConstant.NOROOT);
}
}
public ISvgProcessorResult process(INode root) throws SvgProcessingException {
return process(root, null);
}
/**
* Load in configuration, set initial processorState and create/fill-in context of the processor
*
* @param converterProps that contains configuration properties and operations
*/
void performSetup(INode root, ISvgConverterProperties converterProps) {
processorState = new ProcessorState();
if (converterProps.getRendererFactory() != null) {
rendererFactory = converterProps.getRendererFactory();
}
context = new SvgProcessorContext(converterProps);
cssResolver = new SvgStyleResolver(root, context);
new SvgFontProcessor(context).addFontFaceFonts(cssResolver);
//TODO RND-1042
namedObjects = new HashMap<>();
cssContext = new SvgCssContext();
}
/**
* Start the depth-first traversal of the INode tree, pushing the results on the stack
*
* @param startingNode node to start on
*/
void executeDepthFirstTraversal(INode startingNode) {
//Create and push rootNode
if (startingNode instanceof IElementNode && !rendererFactory.isTagIgnored((IElementNode) startingNode)) {
IElementNode rootElementNode = (IElementNode) startingNode;
ISvgNodeRenderer startingRenderer = rendererFactory.createSvgNodeRendererForTag(rootElementNode, null);
if (startingRenderer != null) {
Map attributesAndStyles = cssResolver.resolveStyles(startingNode, cssContext);
startingRenderer.setAttributesAndStyles(attributesAndStyles);
processorState.push(startingRenderer);
for (INode rootChild : startingNode.childNodes()) {
visit(rootChild);
}
}
}
}
/**
* Extract result from internal processorState and clean up afterwards
*
* @return Root renderer of the processed SVG
*/
private ISvgNodeRenderer createResultAndClean() {
return processorState.pop();
}
/**
* Recursive visit of the object tree, depth-first, processing the visited node and calling visit on its children.
* Visit responsibilities for element nodes:
* - Assign styles(CSS & attributes) to element
* - Create Renderer based on element
* - push & pop renderer to stack
* Visit responsibilities for text nodes
* - add text to parent object
*
* @param node INode to visit
*/
private void visit(INode node) {
if (node instanceof IElementNode) {
IElementNode element = (IElementNode) node;
if (!rendererFactory.isTagIgnored(element)) {
ISvgNodeRenderer renderer = createRenderer(element, processorState.top());
if (renderer != null) {
Map styles = cssResolver.resolveStyles(node, cssContext);
element.setStyles(styles); //For inheritance
renderer.setAttributesAndStyles(styles);//For drawing operations
String attribute = renderer.getAttribute(SvgConstants.Attributes.ID);
if (attribute != null) {
namedObjects.put(attribute, renderer);
}
// don't add the NoDrawOperationSvgNodeRenderer or its subtree to the ISvgNodeRenderer tree
if (processorState.top() instanceof IBranchSvgNodeRenderer && !(renderer instanceof NoDrawOperationSvgNodeRenderer)) {
((IBranchSvgNodeRenderer) processorState.top()).addChild(renderer);
}
processorState.push(renderer);
}
for (INode childNode : element.childNodes()) {
visit(childNode);
}
if (renderer != null) {
processorState.pop();
}
}
} else if (processAsText(node)) {
processText((ITextNode) node);
}
}
/**
* Create renderer based on the passed SVG tag and assign its parent
*
* @param tag SVG tag with all style attributes already assigned
* @param parent renderer of the parent tag
* @return Configured renderer for the tag
*/
private ISvgNodeRenderer createRenderer(IElementNode tag, ISvgNodeRenderer parent) {
return rendererFactory.createSvgNodeRendererForTag(tag, parent);
}
/**
* Check if this node is a text node that needs to be processed by the parent
*
* @param node node to check
* @return true if the node should be processed as text, false otherwise
*/
private boolean processAsText(INode node) {
return node instanceof ITextNode;
}
/**
* Process the text contained in the text-node
*
* @param textNode node containing text to process
*/
private void processText(ITextNode textNode) {
ISvgNodeRenderer parentRenderer = this.processorState.top();
if (parentRenderer instanceof TextSvgNodeRenderer) {
// when svg is parsed by jsoup it leaves all whitespace in text element as is. Meaning that
// tab/space indented xml files will retain their tabs and spaces.
// The following regex replaces all whitespace with a single space.
//TODO(RND-906) evaluate regex and trim methods
String trimmedText = textNode.wholeText().replaceAll("\\s+", " ");
//Trim leading whitespace
trimmedText = SvgTextUtil.trimLeadingWhitespace(trimmedText);
//Trim trailing whitespace
trimmedText = SvgTextUtil.trimTrailingWhitespace(trimmedText);
parentRenderer.setAttribute(SvgConstants.Attributes.TEXT_CONTENT, trimmedText);
}
}
/**
* Find the first element in the node-tree that corresponds with the passed tag-name. Search is performed depth-first
*
* @param node root-node to start with
* @param tagName name of the tag that needs to be fonund
* @return IElementNode
*/
IElementNode findFirstElement(INode node, String tagName) {
LinkedList q = new LinkedList<>();
q.add(node);
while (!q.isEmpty()) {
INode currentNode = q.getFirst();
q.removeFirst();
if (currentNode == null) {
return null;
}
if (currentNode instanceof IElementNode && ((IElementNode) currentNode).name() != null && ((IElementNode) currentNode).name().equals(tagName)) {
return (IElementNode) currentNode;
}
for (INode child : currentNode.childNodes()) {
if (child instanceof IElementNode) {
q.add(child);
}
}
}
return null;
}
}