import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
@Override
protected void transformInternal(ContentReader reader,
                                 ContentWriter writer,
                                 TransformationOptions options) throws Exception
{
    final String sourceMimetype = reader.getMimetype();
    final String sourceExtension = getMimetypeService().getExtension(sourceMimetype);
    final String targetMimetype = writer.getMimetype();
    
    
    if (log.isDebugEnabled())
    {
        StringBuilder msg = new StringBuilder();
        msg.append("Transforming from ").append(sourceMimetype)
           .append(" to ").append(targetMimetype);
        log.debug(msg.toString());
    }
    
    
    OPCPackage pkg = null;
    try 
    {
        File ooxmlTempFile = TempFileProvider.createTempFile(this.getClass().getSimpleName() + "_ooxml", sourceExtension);
        reader.getContent(ooxmlTempFile);
        
        // Load the file
        pkg = OPCPackage.open(ooxmlTempFile.getPath());
        
        // Does it have a thumbnail?
        PackageRelationshipCollection rels = 
            pkg.getRelationshipsByType(PackageRelationshipTypes.THUMBNAIL);
        if (rels.size() > 0)
        {
            // Get the thumbnail part
            PackageRelationship tRel = rels.getRelationship(0);
            PackagePart tPart = pkg.getPart(tRel);
            
            // Write it to the target
            InputStream tStream = tPart.getInputStream();
            writer.putContent( tStream );
            tStream.close();
        }
        else
        {
            log.debug("No thumbnail present in " + reader.toString());
            throw new UnimportantTransformException(NO_THUMBNAIL_PRESENT_IN_FILE + targetMimetype);
        }
    } 
    catch (IOException e) 
    {
       throw new AlfrescoRuntimeException("Unable to transform " + sourceExtension + " file.", e);
    }
    finally
    {
        if (pkg != null)
        {
            pkg.close();
        }
    }
}
 

import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
private void sanitize(BleachSession session, RelationshipSource pkg, Iterable<PackageRelationship> relationships) {
    relationships.iterator().forEachRemaining(packageRelationship -> sanitize(session, pkg, packageRelationship));
}
 

import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
public ExcelReadOnlySharedStringsTable(PackagePart part,
		PackageRelationship rel_ignored) throws IOException, SAXException {
	super(part, rel_ignored);

}
 

import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
public XDGFMasters(PackagePart part, PackageRelationship rel, XDGFDocument document) {
	super(part, rel, document);
}
 

import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
public XDGFBaseContents(PackagePart part, PackageRelationship rel, XDGFDocument document) {
	super(part, rel, document);
}
 

import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
public XDGFPages(PackagePart part, PackageRelationship rel, XDGFDocument document) {
	super(part, rel, document);
}
 

import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
public XDGFMasterContents(PackagePart part, PackageRelationship rel, XDGFDocument document) {
	super(part, rel, document);
}
 

import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
public XDGFPageContents(PackagePart part, PackageRelationship rel, XDGFDocument document) {
	super(part, rel, document);
}
 

import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
public XDGFXMLDocumentPart(PackagePart part, PackageRelationship rel, XDGFDocument document) {
	super(part, rel);
	_document = document;
}
 

import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
private void handleEmbeddedParts(ContentHandler handler)
        throws TikaException, IOException, SAXException {
    try {
        for (PackagePart source : getMainDocumentParts()) {
            for (PackageRelationship rel : source.getRelationships()) {

                URI sourceURI = rel.getSourceURI();
                String sourceDesc;
                if (sourceURI != null) {
                    sourceDesc = getJustFileName(sourceURI.getPath());
                    if (sourceDesc.startsWith("slide")) {
                      sourceDesc += "_";
                    } else {
                      sourceDesc = "";
                    }
                } else {
                    sourceDesc = "";
                }
                if (rel.getTargetMode() == TargetMode.INTERNAL) {
                    PackagePart target;

                    try {
                        target = source.getRelatedPart(rel);
                    } catch (IllegalArgumentException ex) {
                        continue;
                    }

                    String type = rel.getRelationshipType();
                    if (RELATION_OLE_OBJECT.equals(type)
                            && TYPE_OLE_OBJECT.equals(target.getContentType())) {
                        handleEmbeddedOLE(target, handler, sourceDesc + rel.getId());
                    } else if (RELATION_AUDIO.equals(type)
                            || RELATION_IMAGE.equals(type)
                            || RELATION_PACKAGE.equals(type)
                            || RELATION_OLE_OBJECT.equals(type)) {
                        handleEmbeddedFile(target, handler, sourceDesc + rel.getId());
                    }
                }
            }
        }
    } catch (InvalidFormatException e) {
        throw new TikaException("Broken OOXML file", e);
    }
}
 

import org.apache.poi.openxml4j.opc.PackageRelationship; //导入依赖的package包/类
/**
    * Replace a relationship by a fake on using the {@link #pushDummyFile(OPCPackage) dummy file} so MS Office does not crash
    * because the relationship does not exist.
    * @param pkg Where the relationship must be removed from
    * @param relationship The relationship to replace
    * @see #pushDummyFile
    */
   private void replaceRelationship(RelationshipSource pkg, PackageRelationship relationship) {
   	String rId = relationship.getId();
   	
   	pkg.removeRelationship(rId);
   	pkg.addRelationship(DUMMY_PACKAGE_PART_NAME, TargetMode.INTERNAL, Relations.OPENXML_OLE_OBJECT, rId);
}