/* ====================================================================
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.
==================================================================== */
package org.apache.poi;
import java.io.
IOException;
import java.io.
InputStream;
import java.util.
Iterator;
import org.apache.poi.openxml4j.exceptions.
InvalidFormatException;
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.
PackagingURIHelper;
import org.apache.poi.util.
POILogFactory;
import org.apache.poi.util.
POILogger;
/**
* Represents a descriptor of a OOXML relation.
*/
public abstract class
POIXMLRelation {
private static final
POILogger log =
POILogFactory.
getLogger(
POIXMLRelation.class);
/**
* Describes the content stored in a part.
*/
private
String _type;
/**
* The kind of connection between a source part and a target part in a package.
*/
private
String _relation;
/**
* The path component of a pack URI.
*/
private
String _defaultName;
/**
* Defines what object is used to construct instances of this relationship
*/
private
Class<? extends
POIXMLDocumentPart>
_cls;
/**
* Instantiates a POIXMLRelation.
*
* @param type content type
* @param rel relationship
* @param defaultName default item name
* @param cls defines what object is used to construct instances of this relationship
*/
public
POIXMLRelation(
String type,
String rel,
String defaultName,
Class<? extends
POIXMLDocumentPart>
cls) {
_type =
type;
_relation =
rel;
_defaultName =
defaultName;
_cls =
cls;
}
/**
* Instantiates a POIXMLRelation.
*
* @param type content type
* @param rel relationship
* @param defaultName default item name
*/
public
POIXMLRelation(
String type,
String rel,
String defaultName) {
this(
type,
rel,
defaultName, null);
}
/**
* Return the content type. Content types define a media type, a subtype, and an
* optional set of parameters, as defined in RFC 2616.
*
* @return the content type
*/
public
String getContentType() {
return
_type;
}
/**
* Return the relationship, the kind of connection between a source part and a target part in a package.
* Relationships make the connections between parts directly discoverable without looking at the content
* in the parts, and without altering the parts themselves.
*
* @return the relationship
*/
public
String getRelation() {
return
_relation;
}
/**
* Return the default part name. Part names are used to refer to a part in the context of a
* package, typically as part of a URI.
*
* @return the default part name
*/
public
String getDefaultFileName() {
return
_defaultName;
}
/**
* Returns the filename for the nth one of these, e.g. /xl/comments4.xml
*
* @param index the suffix for the document type
* @return the filename including the suffix
*/
public
String getFileName(int
index) {
if(!
_defaultName.
contains("#")) {
// Generic filename in all cases
return
getDefaultFileName();
}
return
_defaultName.
replace("#",
Integer.
toString(
index));
}
/**
* Returns the index of the filename within the package for the given part.
* e.g. 4 for /xl/comments4.xml
*
* @param part the part to read the suffix from
* @return the suffix
*/
public
Integer getFileNameIndex(
POIXMLDocumentPart part) {
String regex =
_defaultName.
replace("#", "(\\d+)");
return
Integer.
valueOf(
part.
getPackagePart().
getPartName().
getName().
replaceAll(
regex, "$1"));
}
/**
* Return type of the object used to construct instances of this relationship
*
* @return the class of the object used to construct instances of this relation
*/
public
Class<? extends
POIXMLDocumentPart>
getRelationClass(){
return
_cls;
}
/**
* Fetches the InputStream to read the contents, based
* of the specified core part, for which we are defined
* as a suitable relationship
*
* @since 3.16-beta3
*/
public
InputStream getContents(
PackagePart corePart) throws
IOException,
InvalidFormatException {
PackageRelationshipCollection prc =
corePart.
getRelationshipsByType(
getRelation());
Iterator<
PackageRelationship>
it =
prc.
iterator();
if(
it.
hasNext()) {
PackageRelationship rel =
it.
next();
PackagePartName relName =
PackagingURIHelper.
createPartName(
rel.
getTargetURI());
PackagePart part =
corePart.
getPackage().
getPart(
relName);
return
part.
getInputStream();
}
log.
log(
POILogger.
WARN, "No part " +
getDefaultFileName() + " found");
return null;
}
}