org.apache.poi.POIXMLDocumentPart Maven / Gradle / Ivy
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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
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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,
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See the License for the specific language governing permissions and
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package org.apache.poi;
import java.io.IOException;
import java.net.URI;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;
import org.apache.poi.openxml4j.exceptions.InvalidFormatException;
import org.apache.poi.openxml4j.exceptions.OpenXML4JException;
import org.apache.poi.openxml4j.exceptions.PartAlreadyExistsException;
import org.apache.poi.openxml4j.opc.OPCPackage;
import org.apache.poi.openxml4j.opc.PackagePart;
import org.apache.poi.openxml4j.opc.PackagePartName;
import org.apache.poi.openxml4j.opc.PackageRelationship;
import org.apache.poi.openxml4j.opc.PackageRelationshipCollection;
import org.apache.poi.openxml4j.opc.PackageRelationshipTypes;
import org.apache.poi.openxml4j.opc.PackagingURIHelper;
import org.apache.poi.openxml4j.opc.TargetMode;
import org.apache.poi.util.POILogFactory;
import org.apache.poi.util.POILogger;
import org.apache.xmlbeans.XmlOptions;
/**
* Represents an entry of a OOXML package.
*
*
* Each POIXMLDocumentPart keeps a reference to the underlying a {@link org.apache.poi.openxml4j.opc.PackagePart}.
*
*
* @author Yegor Kozlov
*/
public class POIXMLDocumentPart {
private static final POILogger logger = POILogFactory.getLogger(POIXMLDocumentPart.class);
public static final XmlOptions DEFAULT_XML_OPTIONS;
static {
DEFAULT_XML_OPTIONS = new XmlOptions();
DEFAULT_XML_OPTIONS.setSaveOuter();
DEFAULT_XML_OPTIONS.setUseDefaultNamespace();
DEFAULT_XML_OPTIONS.setSaveAggressiveNamespaces();
DEFAULT_XML_OPTIONS.setCharacterEncoding("UTF-8");
}
private PackagePart packagePart;
private PackageRelationship packageRel;
private POIXMLDocumentPart parent;
private Map relations = new LinkedHashMap();
/**
* Counter that provides the amount of incoming relations from other parts
* to this part.
*/
private int relationCounter = 0;
int incrementRelationCounter() {
relationCounter++;
return relationCounter;
}
int decrementRelationCounter() {
relationCounter--;
return relationCounter;
}
int getRelationCounter() {
return relationCounter;
}
/**
* Construct POIXMLDocumentPart representing a "core document" package part.
*/
public POIXMLDocumentPart(OPCPackage pkg) {
PackageRelationship coreRel = pkg.getRelationshipsByType(PackageRelationshipTypes.CORE_DOCUMENT).getRelationship(0);
this.packagePart = pkg.getPart(coreRel);
this.packageRel = coreRel;
}
/**
* Creates new POIXMLDocumentPart - called by client code to create new parts from scratch.
*
* @see #createRelationship(POIXMLRelation, POIXMLFactory, int, boolean)
*/
public POIXMLDocumentPart(){
}
/**
* Creates an POIXMLDocumentPart representing the given package part and relationship.
* Called by {@link #read(POIXMLFactory, java.util.Map)} when reading in an exisiting file.
*
* @param part - The package part that holds xml data represenring this sheet.
* @param rel - the relationship of the given package part
* @see #read(POIXMLFactory, java.util.Map)
*/
public POIXMLDocumentPart(PackagePart part, PackageRelationship rel){
this.packagePart = part;
this.packageRel = rel;
}
/**
* Creates an POIXMLDocumentPart representing the given package part, relationship and parent
* Called by {@link #read(POIXMLFactory, java.util.Map)} when reading in an exisiting file.
*
* @param parent - Parent part
* @param part - The package part that holds xml data represenring this sheet.
* @param rel - the relationship of the given package part
* @see #read(POIXMLFactory, java.util.Map)
*/
public POIXMLDocumentPart(POIXMLDocumentPart parent, PackagePart part, PackageRelationship rel){
this.packagePart = part;
this.packageRel = rel;
this.parent = parent;
}
/**
* When you open something like a theme, call this to
* re-base the XML Document onto the core child of the
* current core document
*/
protected final void rebase(OPCPackage pkg) throws InvalidFormatException {
PackageRelationshipCollection cores =
packagePart.getRelationshipsByType(PackageRelationshipTypes.CORE_DOCUMENT);
if(cores.size() != 1) {
throw new IllegalStateException(
"Tried to rebase using " + PackageRelationshipTypes.CORE_DOCUMENT +
" but found " + cores.size() + " parts of the right type"
);
}
packageRel = cores.getRelationship(0);
packagePart = packagePart.getRelatedPart(packageRel);
}
/**
* Provides access to the underlying PackagePart
*
* @return the underlying PackagePart
*/
public final PackagePart getPackagePart(){
return packagePart;
}
/**
* Provides access to the PackageRelationship that identifies this POIXMLDocumentPart
*
* @return the PackageRelationship that identifies this POIXMLDocumentPart
*/
public final PackageRelationship getPackageRelationship(){
return packageRel;
}
/**
* Returns the list of child relations for this POIXMLDocumentPart
*
* @return child relations
*/
public final List getRelations(){
return Collections.unmodifiableList(new ArrayList(relations.values()));
}
/**
* Returns the target {@link POIXMLDocumentPart}, where a
* {@link PackageRelationship} is set from the {@link PackagePart} of this
* {@link POIXMLDocumentPart} to the {@link PackagePart} of the target
* {@link POIXMLDocumentPart} with a {@link PackageRelationship#getId()}
* matching the given parameter value.
*
* @param id
* The relation id to look for
* @return the target part of the relation, or null, if none exists
*/
public final POIXMLDocumentPart getRelationById(String id) {
return relations.get(id);
}
/**
* Returns the {@link PackageRelationship#getId()} of the
* {@link PackageRelationship}, that sources from the {@link PackagePart} of
* this {@link POIXMLDocumentPart} to the {@link PackagePart} of the given
* parameter value.
*
* @param part
* The {@link POIXMLDocumentPart} for which the according
* relation-id shall be found.
* @return The value of the {@link PackageRelationship#getId()} or null, if
* parts are not related.
*/
public final String getRelationId(POIXMLDocumentPart part) {
Iterator> iter = relations.entrySet().iterator();
while (iter.hasNext())
{
Entry entry = iter.next();
if (entry.getValue() == part) {
return entry.getKey();
}
}
return null;
}
/**
* Add a new child POIXMLDocumentPart
*
* @param part the child to add
*/
public final void addRelation(String id,POIXMLDocumentPart part){
relations.put(id,part);
part.incrementRelationCounter();
}
/**
* Remove the relation to the specified part in this package and remove the
* part, if it is no longer needed.
*/
protected final void removeRelation(POIXMLDocumentPart part){
removeRelation(part,true);
}
/**
* Remove the relation to the specified part in this package and remove the
* part, if it is no longer needed and flag is set to true.
*
* @param part
* The related part, to which the relation shall be removed.
* @param removeUnusedParts
* true, if the part shall be removed from the package if not
* needed any longer.
*/
protected final boolean removeRelation(POIXMLDocumentPart part, boolean removeUnusedParts){
String id = getRelationId(part);
if (id == null) {
// part is not related with this POIXMLDocumentPart
return false;
}
/* decrement usage counter */
part.decrementRelationCounter();
/* remove packagepart relationship */
getPackagePart().removeRelationship(id);
/* remove POIXMLDocument from relations */
relations.remove(id);
if (removeUnusedParts) {
/* if last relation to target part was removed, delete according target part */
if (part.getRelationCounter() == 0) {
try {
part.onDocumentRemove();
} catch (IOException e) {
throw new POIXMLException(e);
}
getPackagePart().getPackage().removePart(part.getPackagePart());
}
}
return true;
}
/**
* Returns the parent POIXMLDocumentPart. All parts except root have not-null parent.
*
* @return the parent POIXMLDocumentPart or null for the root element.
*/
public final POIXMLDocumentPart getParent(){
return parent;
}
@Override
public String toString(){
return packagePart == null ? "" : packagePart.toString();
}
/**
* Save the content in the underlying package part.
* Default implementation is empty meaning that the package part is left unmodified.
*
* Sub-classes should override and add logic to marshal the "model" into Ooxml4J.
*
* For example, the code saving a generic XML entry may look as follows:
*
* protected void commit() throws IOException {
* PackagePart part = getPackagePart();
* OutputStream out = part.getOutputStream();
* XmlObject bean = getXmlBean(); //the "model" which holds changes in memory
* bean.save(out, DEFAULT_XML_OPTIONS);
* out.close();
* }
*
*
*/
protected void commit() throws IOException {
}
/**
* Save changes in the underlying OOXML package.
* Recursively fires {@link #commit()} for each package part
*
* @param alreadySaved context set containing already visited nodes
*/
protected final void onSave(Set alreadySaved) throws IOException{
// this usually clears out previous content in the part...
prepareForCommit();
commit();
alreadySaved.add(this.getPackagePart());
for(POIXMLDocumentPart p : relations.values()){
if (!alreadySaved.contains(p.getPackagePart())) {
p.onSave(alreadySaved);
}
}
}
/**
* Ensure that a memory based package part does not have lingering data from previous
* commit() calls.
*
* Note: This is overwritten for some objects, as *PictureData seem to store the actual content
* in the part directly without keeping a copy like all others therefore we need to handle them differently.
*/
protected void prepareForCommit() {
PackagePart part = this.getPackagePart();
if(part != null) {
part.clear();
}
}
/**
* Create a new child POIXMLDocumentPart
*
* @param descriptor the part descriptor
* @param factory the factory that will create an instance of the requested relation
* @return the created child POIXMLDocumentPart
*/
public final POIXMLDocumentPart createRelationship(POIXMLRelation descriptor, POIXMLFactory factory){
return createRelationship(descriptor, factory, -1, false);
}
public final POIXMLDocumentPart createRelationship(POIXMLRelation descriptor, POIXMLFactory factory, int idx){
return createRelationship(descriptor, factory, idx, false);
}
/**
* Create a new child POIXMLDocumentPart
*
* @param descriptor the part descriptor
* @param factory the factory that will create an instance of the requested relation
* @param idx part number
* @param noRelation if true, then no relationship is added.
* @return the created child POIXMLDocumentPart
*/
protected final POIXMLDocumentPart createRelationship(POIXMLRelation descriptor, POIXMLFactory factory, int idx, boolean noRelation){
try {
PackagePartName ppName = PackagingURIHelper.createPartName(descriptor.getFileName(idx));
PackageRelationship rel = null;
PackagePart part = packagePart.getPackage().createPart(ppName, descriptor.getContentType());
if(!noRelation) {
/* only add to relations, if according relationship is being created. */
rel = packagePart.addRelationship(ppName, TargetMode.INTERNAL, descriptor.getRelation());
}
POIXMLDocumentPart doc = factory.newDocumentPart(descriptor);
doc.packageRel = rel;
doc.packagePart = part;
doc.parent = this;
if(!noRelation) {
/* only add to relations, if according relationship is being created. */
addRelation(rel.getId(),doc);
}
return doc;
} catch (PartAlreadyExistsException pae) {
// Return the specific exception so the user knows
// that the name is already taken
throw pae;
} catch (Exception e){
// Give a general wrapped exception for the problem
throw new POIXMLException(e);
}
}
/**
* Iterate through the underlying PackagePart and create child POIXMLFactory instances
* using the specified factory
*
* @param factory the factory object that creates POIXMLFactory instances
* @param context context map containing already visited noted keyed by targetURI
*/
protected void read(POIXMLFactory factory, Map context) throws OpenXML4JException {
PackageRelationshipCollection rels = packagePart.getRelationships();
for (PackageRelationship rel : rels) {
if(rel.getTargetMode() == TargetMode.INTERNAL){
URI uri = rel.getTargetURI();
PackagePart p;
if(uri.getRawFragment() != null) {
/*
* For internal references (e.g. '#Sheet1!A1') the package part is null
*/
p = null;
} else {
PackagePartName relName = PackagingURIHelper.createPartName(uri);
p = packagePart.getPackage().getPart(relName);
if(p == null) {
logger.log(POILogger.ERROR, "Skipped invalid entry " + rel.getTargetURI());
continue;
}
}
if (!context.containsKey(p)) {
POIXMLDocumentPart childPart = factory.createDocumentPart(this, rel, p);
childPart.parent = this;
addRelation(rel.getId(),childPart);
if(p != null){
context.put(p, childPart);
if(p.hasRelationships()) childPart.read(factory, context);
}
}
else {
addRelation(rel.getId(),context.get(p));
}
}
}
}
/**
* Get the PackagePart that is the target of a relationship from this Part.
*
* @param rel The relationship
* @return The target part
* @throws InvalidFormatException
*/
protected PackagePart getTargetPart(PackageRelationship rel) throws InvalidFormatException {
return getPackagePart().getRelatedPart(rel);
}
/**
* Fired when a new package part is created
*/
protected void onDocumentCreate() throws IOException {
}
/**
* Fired when a package part is read
*/
protected void onDocumentRead() throws IOException {
}
/**
* Fired when a package part is about to be removed from the package
*/
protected void onDocumentRemove() throws IOException {
}
}