org.mustangproject.ZUGFeRD.DXExporterFromA3 Maven / Gradle / Ivy
Show all versions of library Show documentation
/**
* *********************************************************************
*
* Copyright 2020 Jochen Staerk
*
* Use is subject to license terms.
*
* Licensed 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.mustangproject.ZUGFeRD;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.GregorianCalendar;
import java.util.HashMap;
import java.util.Map;
import javax.xml.transform.TransformerException;
import org.apache.pdfbox.Loader;
import org.apache.pdfbox.cos.COSArray;
import org.apache.pdfbox.cos.COSBase;
import org.apache.pdfbox.cos.COSDictionary;
import org.apache.pdfbox.cos.COSName;
import org.apache.pdfbox.cos.COSObject;
import org.apache.pdfbox.io.IOUtils;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.pdmodel.PDDocumentCatalog;
import org.apache.pdfbox.pdmodel.PDDocumentInformation;
import org.apache.pdfbox.pdmodel.PDDocumentNameDictionary;
import org.apache.pdfbox.pdmodel.PDEmbeddedFilesNameTreeNode;
import org.apache.pdfbox.pdmodel.common.PDMetadata;
import org.apache.pdfbox.pdmodel.common.filespecification.PDComplexFileSpecification;
import org.apache.pdfbox.pdmodel.common.filespecification.PDEmbeddedFile;
import org.apache.pdfbox.pdmodel.documentinterchange.logicalstructure.PDMarkInfo;
import org.apache.pdfbox.pdmodel.documentinterchange.logicalstructure.PDStructureTreeRoot;
import org.apache.pdfbox.pdmodel.graphics.color.PDOutputIntent;
import org.apache.xmpbox.XMPMetadata;
import org.apache.xmpbox.schema.AdobePDFSchema;
import org.apache.xmpbox.schema.DublinCoreSchema;
import org.apache.xmpbox.schema.PDFAIdentificationSchema;
import org.apache.xmpbox.schema.XMPBasicSchema;
import org.apache.xmpbox.type.ArrayProperty;
import org.apache.xmpbox.type.BadFieldValueException;
import org.apache.xmpbox.xml.DomXmpParser;
import org.apache.xmpbox.xml.XmpParsingException;
import org.apache.xmpbox.xml.XmpSerializer;
import org.mustangproject.EStandard;
import org.mustangproject.FileAttachment;
import jakarta.activation.DataSource;
import jakarta.activation.FileDataSource;
public class DXExporterFromA3 extends ZUGFeRDExporterFromA3 {
protected PDFAConformanceLevel conformanceLevel = PDFAConformanceLevel.UNICODE;
protected ArrayList fileAttachments = new ArrayList<>();
/**
* This flag controls whether or not the metadata is overwritten, or kind of merged.
* The merging probably needs to be overhauled, but for my purpose it was good enough.
*/
protected boolean overwrite = true;
private boolean disableAutoClose;
private boolean fileAttached = false;
private Profile profile = null;
private boolean documentPrepared = false;
/**
* Data (XML invoice) to be added to the ZUGFeRD PDF. It may be externally set,
* in which case passing a IZUGFeRDExportableTransaction is not necessary. By
* default it is null meaning the caller needs to pass a
* IZUGFeRDExportableTransaction for the XML to be populated.
*/
protected PDMetadata metadata = null;
/**
* Producer attribute for PDF
*/
protected String producer = "mustangproject";
/**
* Author/Creator attribute for PDF
*/
protected String creator = "mustangproject";
/**
* CreatorTool
*/
protected String creatorTool = "mustangproject";
/**
* @deprecated author is never set yet
*/
@Deprecated
protected String author;
/**
* @deprecated title is never set yet
*/
@Deprecated
protected String title;
/**
* @deprecated subject is never set yet
*/
@Deprecated
protected String subject;
/**
* OrderX document type. As of version 1.0 it may be
* ORDER, ORDER_RESPONSE, or ORDER_CHANGE
*/
protected String despatchAdviceDocumentType = "DESPATCHADVICE";
private boolean attachZUGFeRDHeaders = true;
/**
* Makes A PDF/A3a-compliant document from a PDF-A1 compliant document (on the
* metadata level, this will not e.g. convert graphics to JPG-2000)
*
* @param pdfFilename filename of an PDF/A1 compliant document
*/
@Override
public DXExporterFromA3 load(String pdfFilename) throws IOException {
ensurePDFIsValid(new FileDataSource(pdfFilename));
try (FileInputStream pdf = new FileInputStream(pdfFilename)) {
return load(readAllBytes(pdf));
}
}
@Override
public IXMLProvider getProvider() {
return xmlProvider;
}
@Override
public DXExporterFromA3 setProfile(Profile p) {
this.profile = p;
if (xmlProvider != null) {
xmlProvider.setProfile(p);
}
return this;
}
@Override
public DXExporterFromA3 setProfile(String profilename) {
this.profile = Profiles.getByName(profilename);
if (xmlProvider != null) {
xmlProvider.setProfile(this.profile);
}
return this;
}
@Override
public DXExporterFromA3 addAdditionalFile(String name, byte[] content) {
fileAttachments.add(new FileAttachment(name, "text/xml", "Supplement", content).setDescription("ZUGFeRD extension/additional data"));
return this;
}
/**
* Makes A PDF/A3a-compliant document from a PDF-A1 compliant document (on the
* metadata level, this will not e.g. convert graphics to JPG-2000)
*
* @param pdfBinary binary of a PDF/A1 compliant document
*/
@Override
public DXExporterFromA3 load(byte[] pdfBinary) throws IOException {
ensurePDFIsValid(new ByteArrayDataSource(new ByteArrayInputStream(pdfBinary)));
doc = Loader.loadPDF(pdfBinary);
return this;
}
public DXExporterFromA3() {
super();
}
@Override
public void attachFile(FileAttachment file) {
fileAttachments.add(file);
}
@Override
public void attachFile(String filename, byte[] data, String mimetype, String relation) {
FileAttachment fa = new FileAttachment(filename, mimetype, relation, data);
fileAttachments.add(fa);
}
/***
* Perform the final export to a now ZUGFeRD-enriched PDF file
* @param ZUGFeRDfilename the pdf file name
* @throws IOException if anything is wrong in the target location
*/
@Override
public void export(String ZUGFeRDfilename) throws IOException {
if (!documentPrepared) {
prepareDocument();
}
if ((!fileAttached) && (attachZUGFeRDHeaders)) {
throw new IOException(
"File must be attached (usually with setTransaction) before perfoming this operation");
}
doc.save(ZUGFeRDfilename);
if (!disableAutoClose) {
close();
}
}
@Override
public void close() throws IOException {
if (doc != null) {
doc.close();
}
}
/***
* Perform the final export to a now ZUGFeRD-enriched PDF file as OutputStream
* @param output the OutputStream
* @throws IOException if anything is wrong in the OutputStream
*/
@Override
public void export(OutputStream output) throws IOException {
if (!documentPrepared) {
prepareDocument();
}
if ((!fileAttached) && (attachZUGFeRDHeaders)) {
throw new IOException(
"File must be attached (usually with setTransaction) before perfoming this operation");
}
doc.save(output);
if (!disableAutoClose) {
close();
}
}
/**
* Embeds an external file (generic - any type allowed) in the PDF.
* The embedding is done in the default PDF document.
*
* @param filename name of the file that will become attachment name in the PDF
* @param relationship how the file relates to the content, e.g. "Alternative"
* @param description Human-readable description of the file content
* @param subType type of the data e.g. could be "text/xml" - mime like
* @param data the binary data of the file/attachment
* @throws IOException if anything is wrong with filename
*/
@Override
public void PDFAttachGenericFile(String filename, String relationship, String description,
String subType, byte[] data) throws IOException {
PDFAttachGenericFile(this.doc, filename, relationship, description, subType, data);
}
/**
* Embeds an external file (generic - any type allowed) in the PDF.
*
* @param doc PDDocument to attach the file to.
* @param filename name of the file that will become attachment name in the PDF
* @param relationship how the file relates to the content, e.g. "Alternative"
* @param description Human-readable description of the file content
* @param subType type of the data e.g. could be "text/xml" - mime like
* @param data the binary data of the file/attachment
* @throws IOException if anything is wrong with filename
*/
@Override
public void PDFAttachGenericFile(PDDocument doc, String filename, String relationship, String description,
String subType, byte[] data) throws IOException {
fileAttached = true;
PDComplexFileSpecification fs = new PDComplexFileSpecification();
fs.setFile(filename);
COSDictionary dict = fs.getCOSObject();
dict.setName("AFRelationship", relationship);
dict.setString("UF", filename);
dict.setString("Desc", description);
ByteArrayInputStream fakeFile = new ByteArrayInputStream(data);
PDEmbeddedFile ef = new PDEmbeddedFile(doc, fakeFile);
// ef.addCompression();
ef.setSubtype(subType);
ef.setSize(data.length);
ef.setCreationDate(new GregorianCalendar());
ef.setModDate(Calendar.getInstance());
fs.setEmbeddedFile(ef);
// In addition make sure the embedded file is set under /UF
dict = fs.getCOSObject();
COSDictionary efDict = (COSDictionary) dict.getDictionaryObject(COSName.EF);
COSBase lowerLevelFile = efDict.getItem(COSName.F);
efDict.setItem(COSName.UF, lowerLevelFile);
// now add the entry to the embedded file tree and set in the document.
PDDocumentNameDictionary names = new PDDocumentNameDictionary(doc.getDocumentCatalog());
PDEmbeddedFilesNameTreeNode efTree = names.getEmbeddedFiles();
if (efTree == null) {
efTree = new PDEmbeddedFilesNameTreeNode();
}
Map namesMap = new HashMap<>();
Map oldNamesMap = efTree.getNames();
if (oldNamesMap != null) {
for (String key : oldNamesMap.keySet()) {
namesMap.put(key, oldNamesMap.get(key));
}
}
namesMap.put(filename, fs);
efTree.setNames(namesMap);
names.setEmbeddedFiles(efTree);
doc.getDocumentCatalog().setNames(names);
// AF entry (Array) in catalog with the FileSpec
COSBase AFEntry = doc.getDocumentCatalog().getCOSObject().getItem("AF");
if ((AFEntry == null)) {
COSArray cosArray = new COSArray();
cosArray.add(fs);
doc.getDocumentCatalog().getCOSObject().setItem("AF", cosArray);
} else if (AFEntry instanceof COSArray) {
COSArray cosArray = (COSArray) AFEntry;
cosArray.add(fs);
doc.getDocumentCatalog().getCOSObject().setItem("AF", cosArray);
} else if ((AFEntry instanceof COSObject) &&
((COSObject) AFEntry).getObject() instanceof COSArray) {
COSArray cosArray = (COSArray) ((COSObject) AFEntry).getObject();
cosArray.add(fs);
} else {
throw new IOException("Unexpected object type for PDFDocument/Catalog/COSDictionary/Item(AF)");
}
}
/**
* Sets the ZUGFeRD XML data to be attached as a single byte array. This is
* useful for use-cases where the XML has already been produced by some external
* API or component.
*
* @param zugferdData XML data to be set as a byte array (XML file in raw form).
* @throws IOException (should not happen)
*/
@Override
public DXExporterFromA3 setXML(byte[] zugferdData) throws IOException {
CustomXMLProvider cus = new CustomXMLProvider();
// As of late 2022 the Delivery-X standard is not yet published. See specification:
// Die digitale Ablösung des Papier-Lieferscheins, Version 1.1, April 2022
// Chapter 7.1 XMP-Erweiterungsschema für PDF/A-3
// http://docplayer.org/230301085-Der-digitale-lieferschein-dls.html
cus.setProfile(Profiles.getByName(EStandard.despatchadvice, "PILOT", 1));
cus.setXML(zugferdData);
this.setXMLProvider(cus);
prepare();
return this;
}
/**
* Makes A PDF/A3a-compliant document from a PDF-A1 compliant document (on the
* metadata level, this will not e.g. convert graphics to JPG-2000)
*
* @param pdfSource source to read a PDF/A1 compliant document from
*/
@Override
public DXExporterFromA3 load(InputStream pdfSource) throws IOException {
return load(readAllBytes(pdfSource));
}
@Override
public boolean ensurePDFIsValid(final DataSource dataSource) throws IOException {
return true;
}
private static byte[] readAllBytes(InputStream in) throws IOException {
ByteArrayOutputStream buffer = new ByteArrayOutputStream();
IOUtils.copy(in, buffer);
return buffer.toByteArray();
}
/**
* All files are PDF/A-3, setConformance refers to the level conformance.
*
* PDF/A-3 has three coformance levels, called "A", "U" and "B".
*
* PDF/A-3-B where B means only visually preservable, U -standard for Mustang-
* means visually and unicode preservable and A means full compliance, i.e.
* visually, unicode and structurally preservable and tagged PDF, i.e. useful
* metainformation for blind people.
*
* Feel free to pass "A" as new level if you know what you are doing :-)
*/
@Override
public DXExporterFromA3 setConformanceLevel(PDFAConformanceLevel newLevel) {
conformanceLevel = newLevel;
return this;
}
@Override
public DXExporterFromA3 setCreator(String creator) {
this.creator = creator;
return this;
}
@Override
public DXExporterFromA3 setCreatorTool(String creatorTool) {
this.creatorTool = creatorTool;
return this;
}
@Override
public DXExporterFromA3 setProducer(String producer) {
this.producer = producer;
return this;
}
/**
* Sets the property for DocumentType.
*
* @param DocumentType String, usually DESPATCHADVICE
*
* @return this exporter
*/
public DXExporterFromA3 setDocumentType(String DocumentType)
{
this.despatchAdviceDocumentType = DocumentType;
return this;
}
@Override
protected DXExporterFromA3 setAttachZUGFeRDHeaders(boolean attachHeaders) {
this.attachZUGFeRDHeaders = attachHeaders;
return this;
}
/**
* This will add both the RDF-indication which embedded file is Zugferd and the
* neccessary PDF/A schema extension description to be able to add this
* information to RDF
*
* @param metadata the PDFbox XMPMetadata object
*/
@Override
protected void addXMP(XMPMetadata metadata) {
if (attachZUGFeRDHeaders) {
// As of late 2022 the Delivery-X standard is not yet published. See specification:
// Die digitale Ablösung des Papier-Lieferscheins, Version 1.1, April 2022
// Chapter 7.1 XMP-Erweiterungsschema für PDF/A-3
// http://docplayer.org/230301085-Der-digitale-lieferschein-dls.html
XMPSchemaZugferd zf = new XMPSchemaZugferd(metadata, 1, true, xmlProvider.getProfile(),
"urn:factur-x:pdfa:CrossIndustryDocument:despatchadvice:1p0#", "fx",
"cida.xml", "1.0");
zf.setType(this.despatchAdviceDocumentType);
metadata.addSchema(zf);
// also add the schema extensions...
XMPSchemaPDFAExtensions pdfaex = new XMPSchemaPDFAExtensions(this, metadata, 1, attachZUGFeRDHeaders, EStandard.despatchadvice);
pdfaex.setZUGFeRDVersion(1);
metadata.addSchema(pdfaex);
}
}
/**
* Embeds the Zugferd XML structure in a file named ZUGFeRD-invoice.xml.
*
* @param trans a IZUGFeRDExportableTransaction that provides the data-model to
* populate the XML. This parameter may be null, if so the XML data
* should hav ebeen set via
* setZUGFeRDXMLData(byte[] zugferdData)
* @throws IOException if anything is wrong with already loaded PDF
*/
@Override
public IExporter setTransaction(IExportableTransaction trans) throws IOException {
this.trans = trans;
return prepare();
}
@Override
public IExporter prepare() throws IOException {
prepareDocument();
xmlProvider.generateXML(trans);
String filename = "cida.xml";
PDFAttachGenericFile(doc, filename, "Alternative",
"Delivery metadata",
"text/xml", xmlProvider.getXML());
for (FileAttachment attachment : fileAttachments) {
PDFAttachGenericFile(doc, attachment.getFilename(), attachment.getRelation(), attachment.getDescription(), attachment.getMimetype(), attachment.getData());
}
return this;
}
/**
* Reads the XMPMetadata from the PDDocument, if it exists.
* Otherwise creates XMPMetadata.
*/
@Override
protected XMPMetadata getXmpMetadata() throws IOException {
PDMetadata meta = doc.getDocumentCatalog().getMetadata();
if ((meta != null) && (meta.getLength() > 0)) {
try {
DomXmpParser xmpParser = new DomXmpParser();
return xmpParser.parse(meta.toByteArray());
} catch (XmpParsingException | IOException e) {
throw new IOException(e);
}
}
return XMPMetadata.createXMPMetadata();
}
@Override
protected byte[] serializeXmpMetadata(XMPMetadata xmpMetadata) throws TransformerException {
ByteArrayOutputStream buffer = new ByteArrayOutputStream();
new XmpSerializer().serialize(xmpMetadata, buffer, true); // see https://github.com/ZUGFeRD/mustangproject/issues/44
return buffer.toByteArray();
}
/**
* Sets the producer if the overwrite flag is set or the producer is not already set.
* Sets the PDFVersion to 1.4 if the field is empty.
*/
@Override
protected void writeAdobePDFSchema(XMPMetadata xmp) {
AdobePDFSchema pdf = getAdobePDFSchema(xmp);
if (overwrite || isEmpty(pdf.getProducer()))
pdf.setProducer(producer);
}
/**
* Returns the AdobePDFSchema from the XMPMetadata if it exists.
* If the overwrite flag is set or no AdobePDFSchema exists in the XMPMetadata, it is created, added and returned.
*/
@Override
protected AdobePDFSchema getAdobePDFSchema(XMPMetadata xmp) {
AdobePDFSchema pdf = xmp.getAdobePDFSchema();
if (pdf != null)
if (overwrite)
xmp.removeSchema(pdf);
else
return pdf;
return xmp.createAndAddAdobePDFSchema();
}
@Override
protected void writePDFAIdentificationSchema(XMPMetadata xmp) {
PDFAIdentificationSchema pdfaid = getPDFAIdentificationSchema(xmp);
if (overwrite || isEmpty(pdfaid.getConformance())) {
try {
pdfaid.setConformance(conformanceLevel.getLetter());
} catch (BadFieldValueException ex) {
// This should be impossible, because it would occur only if an illegal
// conformance level is supplied,
// however the enum enforces that the conformance level is valid.
throw new RuntimeException(ex);
}
}
pdfaid.setPart(3);
}
@Override
protected PDFAIdentificationSchema getPDFAIdentificationSchema(XMPMetadata xmp) {
PDFAIdentificationSchema pdfaid = xmp.getPDFAIdentificationSchema();
if (pdfaid != null)
if (overwrite)
xmp.removeSchema(pdfaid);
else
return pdfaid;
return xmp.createAndAddPDFAIdentificationSchema();
}
@Override
protected void writeDublinCoreSchema(XMPMetadata xmp) {
DublinCoreSchema dc = getDublinCoreSchema(xmp);
if (dc.getFormat() == null)
dc.setFormat("application/pdf");
if ((overwrite || dc.getCreators() == null || dc.getCreators().isEmpty()) && creator != null)
dc.addCreator(creator);
if ((overwrite || dc.getDates() == null || dc.getDates().isEmpty()) && creator != null)
dc.addDate(Calendar.getInstance());
ArrayProperty titleProperty = dc.getTitleProperty();
if (titleProperty != null) {
if (overwrite && !isEmpty(title)) {
dc.removeProperty(titleProperty);
dc.setTitle(title);
} else if (titleProperty.getElementsAsString().stream().anyMatch("Untitled"::equalsIgnoreCase)) {
// remove unfitting ghostscript default
dc.removeProperty(titleProperty);
}
} else if (!isEmpty(title)) {
dc.setTitle(title);
}
}
@Override
protected DublinCoreSchema getDublinCoreSchema(XMPMetadata xmp) {
DublinCoreSchema dc = xmp.getDublinCoreSchema();
if (dc != null)
if (overwrite)
xmp.removeSchema(dc);
else
return dc;
return xmp.createAndAddDublinCoreSchema();
}
@Override
protected void writeXMLBasicSchema(XMPMetadata xmp) {
XMPBasicSchema xsb = getXmpBasicSchema(xmp);
if (overwrite || isEmpty(xsb.getCreatorTool()) || "UnknownApplication".equals(xsb.getCreatorTool()))
xsb.setCreatorTool(creatorTool);
if (overwrite || xsb.getCreateDate() == null)
xsb.setCreateDate(Calendar.getInstance());
}
@Override
protected XMPBasicSchema getXmpBasicSchema(XMPMetadata xmp) {
XMPBasicSchema xsb = xmp.getXMPBasicSchema();
if (xsb != null)
if (overwrite)
xmp.removeSchema(xsb);
else
return xsb;
return xmp.createAndAddXMPBasicSchema();
}
@Override
protected void writeDocumentInformation() {
String fullProducer = producer + " (via mustangproject.org " + Version.VERSION + ")";
PDDocumentInformation info = doc.getDocumentInformation();
if (overwrite || info.getCreationDate() == null)
info.setCreationDate(Calendar.getInstance());
if (overwrite || info.getModificationDate() == null)
info.setModificationDate(Calendar.getInstance());
if (overwrite || (isEmpty(info.getAuthor()) && !isEmpty(author)))
info.setAuthor(author);
if (overwrite || (isEmpty(info.getProducer()) && !isEmpty(fullProducer)))
info.setProducer(fullProducer);
if (overwrite || (isEmpty(info.getCreator()) && !isEmpty(creator)))
info.setCreator(creator);
if (overwrite || (isEmpty(info.getTitle()) && !isEmpty(title)))
info.setTitle(title);
if (overwrite || (isEmpty(info.getSubject()) && !isEmpty(subject)))
info.setSubject(subject);
}
/**
* Adds an OutputIntent and the sRGB color profile if no OutputIntent exist
*/
@Override
protected void addSRGBOutputIntend() throws IOException {
if (!doc.getDocumentCatalog().getOutputIntents().isEmpty()) {
return;
}
try {
InputStream colorProfile = Thread.currentThread().getContextClassLoader().getResourceAsStream("sRGB.icc");
if (colorProfile != null) {
PDOutputIntent intent = new PDOutputIntent(doc, colorProfile);
intent.setInfo("sRGB IEC61966-2.1");
intent.setOutputCondition("sRGB IEC61966-2.1");
intent.setOutputConditionIdentifier("sRGB IEC61966-2.1");
intent.setRegistryName("http://www.color.org");
doc.getDocumentCatalog().addOutputIntent(intent);
}
} catch (IOException e) {
throw e;
}
}
/**
* Adds a MarkInfo element to the PDF if it doesn't already exist and sets it as marked.
*/
@Override
protected void setMarked() {
PDDocumentCatalog catalog = doc.getDocumentCatalog();
if (catalog.getMarkInfo() == null) {
catalog.setMarkInfo(new PDMarkInfo(doc.getPages().getCOSObject()));
}
catalog.getMarkInfo().setMarked(true);
}
/**
* Adds a StructureTreeRoot element to the PDF if it doesn't already exist.
*/
@Override
protected void addStructureTreeRoot() {
if (doc.getDocumentCatalog().getStructureTreeRoot() == null) {
doc.getDocumentCatalog().setStructureTreeRoot(new PDStructureTreeRoot());
}
}
/**
* @return if pdf file will be automatically closed after adding ZF
*/
@Override
public boolean isAutoCloseDisabled() {
return disableAutoClose;
}
/**
* @param disableAutoClose prevent PDF file from being closed after adding ZF
*/
@Override
public DXExporterFromA3 disableAutoClose(boolean disableAutoClose) {
this.disableAutoClose = disableAutoClose;
return this;
}
@Override
protected void setXMLProvider(IXMLProvider p) {
this.xmlProvider = p;
if (profile != null) {
xmlProvider.setProfile(profile);
}
}
@Override
public DXExporterFromA3 setZUGFeRDVersion(int version) {
DAPullProvider z2p = new DAPullProvider();
setXMLProvider(z2p);
return this;
}
/**
* Utility method inspired by apache commons-lang3 StringUtils.
*
* @param string the string to test
* @return true if the string is null or empty
*/
private boolean isEmpty(String string) {
return string == null || string.isEmpty();
}
}