close resource leaks and use tryWithResource

2017-06-02 15:24:03 +02:00
parent a771b1e769
commit faf4d1def3
8 changed files with 258 additions and 236 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,4 @@ PDFA*.pdf
 target/
 pom.xml.*
 bin/
+/.gradle/
--- a/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDExportException.java
+++ b/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDExportException.java
@@ -1,7 +1,12 @@
 package org.mustangproject.ZUGFeRD;

 public class ZUGFeRDExportException extends RuntimeException {
-    public ZUGFeRDExportException() {
+    /**
+	 *
+	 */
+	private static final long serialVersionUID = 1L;
+
+	public ZUGFeRDExportException() {
    }

    public ZUGFeRDExportException(String message) {
--- a/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDExporter.java
+++ b/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDExporter.java
@@ -28,19 +28,12 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;

-import javax.activation.FileDataSource;
 import javax.xml.bind.JAXBContext;
 import javax.xml.bind.JAXBElement;
 import javax.xml.bind.JAXBException;
 import javax.xml.bind.Marshaller;
 import javax.xml.transform.TransformerException;

-
-import org.apache.xmpbox.XMPMetadata;
-import org.apache.xmpbox.schema.XMPBasicSchema;
-import org.apache.xmpbox.schema.DublinCoreSchema;
-import org.apache.xmpbox.schema.AdobePDFSchema;
-import org.apache.xmpbox.schema.PDFAIdentificationSchema;
 import org.apache.pdfbox.cos.COSArray;
 import org.apache.pdfbox.cos.COSBase;
 import org.apache.pdfbox.cos.COSDictionary;
@@ -58,13 +51,57 @@ import org.apache.pdfbox.preflight.ValidationResult;
 import org.apache.pdfbox.preflight.exception.ValidationException;
 import org.apache.pdfbox.preflight.parser.PreflightParser;
 import org.apache.pdfbox.preflight.utils.ByteArrayDataSource;
+import org.apache.pdfbox.util.Version;
+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.BadFieldValueException;
 import org.apache.xmpbox.xml.XmpSerializer;
-import org.mustangproject.ZUGFeRD.model.*;
+import org.mustangproject.ZUGFeRD.model.AmountType;
+import org.mustangproject.ZUGFeRD.model.CodeType;
+import org.mustangproject.ZUGFeRD.model.CountryIDType;
+import org.mustangproject.ZUGFeRD.model.CreditorFinancialAccountType;
+import org.mustangproject.ZUGFeRD.model.CreditorFinancialInstitutionType;
+import org.mustangproject.ZUGFeRD.model.CrossIndustryDocumentType;
+import org.mustangproject.ZUGFeRD.model.DateTimeType;
+import org.mustangproject.ZUGFeRD.model.DocumentCodeType;
+import org.mustangproject.ZUGFeRD.model.DocumentContextParameterType;
+import org.mustangproject.ZUGFeRD.model.DocumentLineDocumentType;
+import org.mustangproject.ZUGFeRD.model.ExchangedDocumentContextType;
+import org.mustangproject.ZUGFeRD.model.ExchangedDocumentType;
+import org.mustangproject.ZUGFeRD.model.IDType;
+import org.mustangproject.ZUGFeRD.model.IndicatorType;
+import org.mustangproject.ZUGFeRD.model.LogisticsServiceChargeType;
+import org.mustangproject.ZUGFeRD.model.NoteType;
+import org.mustangproject.ZUGFeRD.model.ObjectFactory;
+import org.mustangproject.ZUGFeRD.model.PaymentMeansCodeType;
+import org.mustangproject.ZUGFeRD.model.PercentType;
+import org.mustangproject.ZUGFeRD.model.QuantityType;
+import org.mustangproject.ZUGFeRD.model.SupplyChainEventType;
+import org.mustangproject.ZUGFeRD.model.SupplyChainTradeAgreementType;
+import org.mustangproject.ZUGFeRD.model.SupplyChainTradeDeliveryType;
+import org.mustangproject.ZUGFeRD.model.SupplyChainTradeLineItemType;
+import org.mustangproject.ZUGFeRD.model.SupplyChainTradeSettlementType;
+import org.mustangproject.ZUGFeRD.model.SupplyChainTradeTransactionType;
+import org.mustangproject.ZUGFeRD.model.TaxCategoryCodeType;
+import org.mustangproject.ZUGFeRD.model.TaxRegistrationType;
+import org.mustangproject.ZUGFeRD.model.TaxTypeCodeType;
+import org.mustangproject.ZUGFeRD.model.TextType;
+import org.mustangproject.ZUGFeRD.model.TradeAddressType;
+import org.mustangproject.ZUGFeRD.model.TradeAllowanceChargeType;
+import org.mustangproject.ZUGFeRD.model.TradePartyType;
+import org.mustangproject.ZUGFeRD.model.TradePaymentTermsType;
+import org.mustangproject.ZUGFeRD.model.TradePriceType;
+import org.mustangproject.ZUGFeRD.model.TradeProductType;
+import org.mustangproject.ZUGFeRD.model.TradeSettlementMonetarySummationType;
+import org.mustangproject.ZUGFeRD.model.TradeSettlementPaymentMeansType;
+import org.mustangproject.ZUGFeRD.model.TradeTaxType;

 public class ZUGFeRDExporter implements Closeable {

-	
+
 	private void init() {
 		try {
 			jaxbContext = JAXBContext
@@ -75,7 +112,7 @@ public class ZUGFeRDExporter implements Closeable {
        } catch (JAXBException e) {
            throw new ZUGFeRDExportException("Could not initialize JAXB", e);
        }
-	
+
 	}
 	/**
 	 * * You will need Apache PDFBox. To use the ZUGFeRD exporter, implement
@@ -100,7 +137,7 @@ public class ZUGFeRDExporter implements Closeable {
 	public ZUGFeRDExporter(PDDocument doc2) {
 		init();
 		doc=doc2;
-		
+
 	}

 	private class LineCalc {
@@ -264,12 +301,12 @@ public class ZUGFeRDExporter implements Closeable {
 		 * DecimalFormatSymbols(); symbols.setDecimalSeparator(',');
 		 * symbols.setGroupingSeparator(' ');
 		 * df.setDecimalFormatSymbols(symbols);
-		 * 
+		 *
 		 * but that would not switch off grouping. Although I liked very much
 		 * the (incomplete) "BNF diagram" in
 		 * http://docs.oracle.com/javase/tutorial/i18n/format/decimalFormat.html
 		 * in the end I decided to calculate myself and take eur+sparator+cents
-		 * 
+		 *
 		 * This function will cut off, i.e. floor() subcent values Tests:
 		 * System.err.println(utils.currencyFormat(new BigDecimal(0),
 		 * ".")+"\n"+utils.currencyFormat(new BigDecimal("-1.10"),
@@ -278,7 +315,7 @@ public class ZUGFeRDExporter implements Closeable {
 		 * ",")+"\n"+utils.currencyFormat(new BigDecimal("20000123.3489"),
 		 * ",")+"\n"+utils.currencyFormat(new BigDecimal("20000123.3419"),
 		 * ",")+"\n"+utils.currencyFormat(new BigDecimal("12"), ","));
-		 * 
+		 *
 		 * results 0.00 -1,10 -1,10 -1,01 20000123,34 20000123,34 12,00
 		 */
 		value = value.setScale(scale, BigDecimal.ROUND_HALF_UP); // first, round
@@ -384,13 +421,12 @@ public class ZUGFeRDExporter implements Closeable {
 			 * PreflightDocument (that inherits from PDDocument) This document
 			 * process the end of PDF/A validation.
 			 */
-			PreflightDocument document = parser.getPreflightDocument();
-			document.validate();
-
-			// Get validation result
-			result = document.getResult();
-			document.close();
+			try (PreflightDocument document = parser.getPreflightDocument())	{
+				document.validate();

+				// Get validation result
+				result = document.getResult();
+			}
 		} catch (ValidationException e) {
 			/*
 			 * the parse method can throw a SyntaxValidationException if the PDF
@@ -425,15 +461,25 @@ public class ZUGFeRDExporter implements Closeable {
 	/**
 	 * 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 filename
+	 * @param producer
+	 * @param creator
+	 * @param attachZugferdHeaders
+	 * @return
+	 * @throws IOException
+	 * @throws TransformerException
 	 *
 	 */
-	public PDDocumentCatalog PDFmakeA3compliant(String filename,
-			String producer, String creator, boolean attachZugferdHeaders)
+	public PDDocumentCatalog PDFmakeA3compliant(String filename, String producer, String creator, boolean attachZugferdHeaders)
 			throws IOException, TransformerException {
-		
-		if (!ignoreA1Errors && !isValidA1(new FileInputStream(filename))) {
-			throw new IOException("File is not a valid PDF/A-1 input file");
+
+		try (FileInputStream fis = new FileInputStream(filename))	{
+			boolean validA1 = isValidA1(fis);
+			if (!ignoreA1Errors && !validA1) {
+				throw new IOException("File is not a valid PDF/A-1 input file");
+			}
 		}
+
 		loadPDFA3(filename);

 		return makeDocPDFA3compliant(producer, creator, attachZugferdHeaders);
@@ -452,37 +498,39 @@ public class ZUGFeRDExporter implements Closeable {
 		    baos.write(buf, 0, n);
 		byte[] content = baos.toByteArray();

-		InputStream is1 = new ByteArrayInputStream(content);
-		if (!ignoreA1Errors && !isValidA1(is1)) {
-			throw new IOException("File is not a valid PDF/A-1 input file");
+		try (InputStream is1 = new ByteArrayInputStream(content))	{
+			if (!ignoreA1Errors && !isValidA1(is1)) {
+				throw new IOException("File is not a valid PDF/A-1 input file");
+			}
 		}
+
 		InputStream is2 = new ByteArrayInputStream(content);
 		loadPDFA3(is2);

 		return makeDocPDFA3compliant(producer, creator, attachZugferdHeaders);
-	}	
+	}
 	private PDDocumentCatalog makeDocPDFA3compliant(String producer,
 			String creator, boolean attachZugferdHeaders) throws IOException,
 			TransformerException {
 		String fullProducer = producer + " (via mustangproject.org "
-				+ Version.VERSION + ")";
+				+ Version.getVersion() + ")";

 		PDDocumentCatalog cat = doc.getDocumentCatalog();
 		PDMetadata metadata = new PDMetadata(doc);
 		cat.setMetadata(metadata);
 		XMPMetadata xmp = XMPMetadata.createXMPMetadata();

-                
+
 		PDFAIdentificationSchema pdfaid = new PDFAIdentificationSchema(xmp);
-                
+
 		xmp.addSchema(pdfaid);

 		DublinCoreSchema dc = xmp.createAndAddDublinCoreSchema();
-                
+
 		dc.addCreator(creator);
-                
+
 		XMPBasicSchema xsb = xmp.createAndAddXMPBasicSchema();
-                
+
 		xsb.setCreatorTool(creator);
 		xsb.setCreateDate(GregorianCalendar.getInstance());
 		// PDDocumentInformation pdi=doc.getDocumentInformation();
@@ -530,10 +578,11 @@ public class ZUGFeRDExporter implements Closeable {
                ByteArrayOutputStream baos = new ByteArrayOutputStream();
                serializer.serialize(xmp, baos, false);
                metadata.importXMPMetadata( baos.toByteArray() );
-                
+
 		return cat;
 	}

+	@Override
 	public void close() throws IOException {
 		if (doc != null) {
 			doc.close();
@@ -548,10 +597,10 @@ public class ZUGFeRDExporter implements Closeable {

 	private Totals totals;

-	private String createZugferdXMLForTransaction(IZUGFeRDExportableTransaction trans) {
-		this.trans = trans;
+	private String createZugferdXMLForTransaction(IZUGFeRDExportableTransaction trans1) {
+		this.trans = trans1;
 		this.totals = new Totals();
-		currency = trans.getCurrency();
+		currency = trans1.getCurrency();

 		CrossIndustryDocumentType invoice = xmlFactory
 				.createCrossIndustryDocumentType();
@@ -621,7 +670,7 @@ public class ZUGFeRDExporter implements Closeable {
 		TextType name = xmlFactory.createTextType();
 		name.setValue("RECHNUNG");
 		document.getName().add(name);
-                
+
 		if (trans.getOwnOrganisationFullPlaintextInfo() != null) {
 			NoteType regularInfo = xmlFactory.createNoteType();
 			CodeType regularInfoSubjectCode = xmlFactory.createCodeType();
@@ -633,13 +682,13 @@ public class ZUGFeRDExporter implements Closeable {
 			regularInfo.getContent().add(regularInfoContent);
 			document.getIncludedNote().add(regularInfo);
 		}
-                
+
                if (trans.getReferenceNumber() != null && !new String().equals(trans.getReferenceNumber())){
                    NoteType referenceInfo = xmlFactory.createNoteType();
                    TextType referenceInfoContent = xmlFactory.createTextType();
                    referenceInfoContent.setValue("Ursprungsbeleg: " + trans.getReferenceNumber());
                    referenceInfo.getContent().add(referenceInfoContent);
-                    document.getIncludedNote().add(referenceInfo);            
+                    document.getIncludedNote().add(referenceInfo);
                }

 		return document;
@@ -1385,7 +1434,7 @@ public class ZUGFeRDExporter implements Closeable {
 	 *            data should hav ebeen set via
 	 *            <code>setZUGFeRDXMLData(byte[] zugferdData)</code>
 	 */
-	public void PDFattachZugferdFile(IZUGFeRDExportableTransaction trans)
+	public void PDFattachZugferdFile(IZUGFeRDExportableTransaction trans1)
 			throws IOException {

            if (zugferdData == null) // XML ZUGFeRD data not set externally, needs
@@ -1394,7 +1443,7 @@ public class ZUGFeRDExporter implements Closeable {
                    // create a dummy file stream, this would probably normally be a
                    // FileInputStream

-                    byte[] zugferdRaw = createZugferdXMLForTransaction(trans).getBytes(); //$NON-NLS-1$
+                    byte[] zugferdRaw = createZugferdXMLForTransaction(trans1).getBytes(); //$NON-NLS-1$

                    if ((zugferdRaw[0] == (byte) 0xEF)
                                    && (zugferdRaw[1] == (byte) 0xBB)
@@ -1437,12 +1486,12 @@ public class ZUGFeRDExporter implements Closeable {
 	 *            the binary data of the file/attachment
         * @throws java.io.IOException
 	 */
-	public void PDFAttachGenericFile(PDDocument doc, String filename,
+	public void PDFAttachGenericFile(PDDocument doc1, String filename,
 			String relationship, String description, String subType, byte[] data)
 			throws IOException {
 		PDComplexFileSpecification fs = new PDComplexFileSpecification();
 		fs.setFile(filename);
-                
+

 		COSDictionary dict = fs.getCOSObject();
 		dict.setName("AFRelationship", relationship);
@@ -1450,7 +1499,7 @@ public class ZUGFeRDExporter implements Closeable {
 		dict.setString("Desc", description);

 		ByteArrayInputStream fakeFile = new ByteArrayInputStream(data);
-		PDEmbeddedFile ef = new PDEmbeddedFile(doc, fakeFile);
+		PDEmbeddedFile ef = new PDEmbeddedFile(doc1, fakeFile);
 		ef.setSubtype(subType);
 		ef.setSize(data.length);
 		ef.setCreationDate(new GregorianCalendar());
@@ -1468,7 +1517,7 @@ public class ZUGFeRDExporter implements Closeable {

 		// now add the entry to the embedded file tree and set in the document.
 		PDDocumentNameDictionary names = new PDDocumentNameDictionary(
-				doc.getDocumentCatalog());
+				doc1.getDocumentCatalog());
 		PDEmbeddedFilesNameTreeNode efTree = names.getEmbeddedFiles();
 		if (efTree == null) {
 			efTree = new PDEmbeddedFilesNameTreeNode();
@@ -1486,20 +1535,20 @@ public class ZUGFeRDExporter implements Closeable {
 		efTree.setNames(namesMap);

 		names.setEmbeddedFiles(efTree);
-		doc.getDocumentCatalog().setNames(names);
+		doc1.getDocumentCatalog().setNames(names);

 		// AF entry (Array) in catalog with the FileSpec
-		COSArray cosArray = (COSArray) doc.getDocumentCatalog()
+		COSArray cosArray = (COSArray) doc1.getDocumentCatalog()
 				.getCOSObject().getItem("AF");
 		if (cosArray == null) {
 			cosArray = new COSArray();
 		}
 		cosArray.add(fs);
-		COSDictionary dict2 = doc.getDocumentCatalog().getCOSObject();
+		COSDictionary dict2 = doc1.getDocumentCatalog().getCOSObject();
 		COSArray array = new COSArray();
 		array.add(fs.getCOSObject()); // see below
 	        dict2.setItem("AF",array);
-		doc.getDocumentCatalog().getCOSObject().setItem("AF", cosArray);
+		doc1.getDocumentCatalog().getCOSObject().setItem("AF", cosArray);
 	}

 	/**
@@ -1532,7 +1581,7 @@ public class ZUGFeRDExporter implements Closeable {
 	 *
 	 * @param zUGFeRDConformanceLevel
 	 *            the new conformance level
-	 *           
+	 *
 	 * @deprecated Use {@link #setConformanceLevel(PDFAConformanceLevel)} instead
 	 */
 	@Deprecated
@@ -1555,14 +1604,14 @@ public class ZUGFeRDExporter implements Closeable {
 		metadata.addSchema(zf);

 		XMPSchemaPDFAExtensions pdfaex = new XMPSchemaPDFAExtensions(metadata);
-                
+
 		metadata.addSchema(pdfaex);

 	}

 	/****
 	 * Returns the PDFBox PDF Document
-	 * 
+	 *
 	 * @return PDDocument
 	 */
 	public PDDocument getDoc() {
--- a/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDExporterFromA1Factory.java
+++ b/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDExporterFromA1Factory.java
@@ -9,6 +9,7 @@ import org.apache.pdfbox.preflight.PreflightDocument;
 import org.apache.pdfbox.preflight.exception.ValidationException;
 import org.apache.pdfbox.preflight.parser.PreflightParser;
 import org.apache.pdfbox.preflight.utils.ByteArrayDataSource;
+import org.apache.pdfbox.util.Version;
 import org.apache.xmpbox.XMPMetadata;
 import org.apache.xmpbox.schema.AdobePDFSchema;
 import org.apache.xmpbox.schema.DublinCoreSchema;
@@ -45,9 +46,13 @@ public class ZUGFeRDExporterFromA1Factory {
    public ZUGFeRDExporter loadFromPDFA1(String pdfFilename) throws IOException {
        ensurePDFIsValidA1(new FileDataSource(pdfFilename));

-        PDDocument doc = PDDocument.load(new File(pdfFilename));
-        makePDFA3compliant(doc);
-        return new ZUGFeRDExporter(doc);
+        ZUGFeRDExporter zugFeRDExporter = null;
+        try(PDDocument doc = PDDocument.load(new File(pdfFilename)))	{
+            makePDFA3compliant(doc);
+            zugFeRDExporter = new ZUGFeRDExporter(doc);
+        }
+
+		return zugFeRDExporter;
    }

    /**
@@ -56,12 +61,16 @@ public class ZUGFeRDExporterFromA1Factory {
     *
     * @param pdfBinary binary of a PDF/A1 compliant document
     */
-    public ZUGFeRDExporter loadFromPDFA1(byte[] pdfBinary) throws IOException, TransformerException {
+    public ZUGFeRDExporter loadFromPDFA1(byte[] pdfBinary) throws IOException {
        ensurePDFIsValidA1(new ByteArrayDataSource(new ByteArrayInputStream(pdfBinary)));

-        PDDocument doc = PDDocument.load(pdfBinary);
-        makePDFA3compliant(doc);
-        return new ZUGFeRDExporter(doc);
+        ZUGFeRDExporter zugFeRDExporter;
+        try (PDDocument doc = PDDocument.load(pdfBinary))	{
+            makePDFA3compliant(doc);
+            zugFeRDExporter = new ZUGFeRDExporter(doc);
+        }
+
+		return zugFeRDExporter;
    }

    /**
@@ -70,7 +79,7 @@ public class ZUGFeRDExporterFromA1Factory {
     *
     * @param pdfSource source to read a PDF/A1 compliant document from
     */
-    public ZUGFeRDExporter loadFromPDFA1(InputStream pdfSource) throws IOException, TransformerException {
+    public ZUGFeRDExporter loadFromPDFA1(InputStream pdfSource) throws IOException {
        return loadFromPDFA1(readAllBytes(pdfSource));
    }

@@ -87,7 +96,7 @@ public class ZUGFeRDExporterFromA1Factory {
    }

    private void makePDFA3compliant(PDDocument doc) throws IOException {
-        String fullProducer = producer + " (via mustangproject.org " + Version.VERSION + ")";
+        String fullProducer = producer + " (via mustangproject.org " + Version.getVersion() + ")";

        PDDocumentCatalog cat = doc.getDocumentCatalog();
        PDMetadata metadata = new PDMetadata(doc);
@@ -198,23 +207,22 @@ public class ZUGFeRDExporterFromA1Factory {
    }

    private static boolean getA1ParserValidationResult(PreflightParser parser) throws IOException {
-        PreflightDocument document = null;
-        try {
+		/*
+		 * Parse the PDF file with PreflightParser that inherits from the
+		 * NonSequentialParser. Some additional controls are present to
+		 * check a set of PDF/A requirements. (Stream length consistency,
+		 * EOL after some Keyword...)
+		 */
+        parser.parse();

-			/*
-			 * Parse the PDF file with PreflightParser that inherits from the
-			 * NonSequentialParser. Some additional controls are present to
-			 * check a set of PDF/A requirements. (Stream length consistency,
-			 * EOL after some Keyword...)
-			 */
-            parser.parse();

+        try ( PreflightDocument document = parser.getPreflightDocument()) {
 			/*
 			 * Once the syntax validation is done, the parser can provide a
 			 * PreflightDocument (that inherits from PDDocument) This document
 			 * process the end of PDF/A validation.
 			 */
-            document = parser.getPreflightDocument();
+
            document.validate();

            // Get validation result
@@ -226,10 +234,6 @@ public class ZUGFeRDExporterFromA1Factory {
 			 * instance of ValidationResult
 			 */
            return false;
-        } finally {
-            if (document != null) {
-                document.close();
-            }
        }
    }

--- a/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDImporter.java
+++ b/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDImporter.java
@@ -8,14 +8,13 @@ package org.mustangproject.ZUGFeRD;
 * @author jstaerk
 * */

+import java.io.BufferedInputStream;
 import java.io.ByteArrayInputStream;
+import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;
-import java.io.BufferedInputStream;
-import java.io.FileInputStream;
 import java.util.Map;

-import javax.management.RuntimeErrorException;
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;
@@ -23,7 +22,6 @@ import javax.xml.parsers.ParserConfigurationException;
 import org.apache.pdfbox.pdmodel.PDDocument;
 import org.apache.pdfbox.pdmodel.PDDocumentNameDictionary;
 import org.apache.pdfbox.pdmodel.PDEmbeddedFilesNameTreeNode;
-import org.apache.pdfbox.pdmodel.common.COSObjectable;
 import org.apache.pdfbox.pdmodel.common.filespecification.PDComplexFileSpecification;
 import org.apache.pdfbox.pdmodel.common.filespecification.PDEmbeddedFile;
 import org.w3c.dom.Document;
@@ -62,13 +60,10 @@ public class ZUGFeRDImporter {
 	 * Extracts a ZUGFeRD invoice from a PDF document represented by a file name.
 	 * Errors are just logged to STDOUT.
 	 */
-	public void extract(String pdfFilename)
-	{
-		try
-		{
-			extractLowLevel(new BufferedInputStream(new FileInputStream(pdfFilename)));
-		} catch (IOException ioe)
-		{
+	public void extract(String pdfFilename) {
+		try (BufferedInputStream bis = new BufferedInputStream(new FileInputStream(pdfFilename))) {
+			extractLowLevel(bis);
+		} catch (IOException ioe) {
 			ioe.printStackTrace();
 		}
 	}
@@ -78,18 +73,15 @@ public class ZUGFeRDImporter {
 	 * Errors are reported via exception handling.
 	 */
 	public void extractLowLevel(InputStream pdfStream) throws IOException  {
-		PDDocument doc = null;
-		try {
-			doc = PDDocument.load(pdfStream);
+		PDEmbeddedFilesNameTreeNode etn;
+		try (PDDocument doc = PDDocument.load(pdfStream)) {
 //			PDDocumentInformation info = doc.getDocumentInformation();
-			PDDocumentNameDictionary names = new PDDocumentNameDictionary(
-					doc.getDocumentCatalog());
-			PDEmbeddedFilesNameTreeNode etn;
+			PDDocumentNameDictionary names = new PDDocumentNameDictionary(doc.getDocumentCatalog());
 			etn = names.getEmbeddedFiles();
-			if (etn==null)  {
-				doc.close();
+			if (etn == null)	{
 				return;
 			}
+
 			Map<String, PDComplexFileSpecification> efMap = etn.getNames();
 			// String filePath = "/tmp/";
 			for (String filename : efMap.keySet()) {
@@ -100,8 +92,7 @@ public class ZUGFeRDImporter {
 				if (filename.equals("ZUGFeRD-invoice.xml")) { //$NON-NLS-1$
 					containsMeta = true;

-					PDComplexFileSpecification fileSpec = (PDComplexFileSpecification) efMap
-							.get(filename);
+					PDComplexFileSpecification fileSpec = efMap.get(filename);
 					PDEmbeddedFile embeddedFile = fileSpec.getEmbeddedFile();
 					// String embeddedFilename = filePath + filename;
 					// File file = new File(filePath + filename);
@@ -109,7 +100,7 @@ public class ZUGFeRDImporter {
 					// ByteArrayOutputStream fileBytes=new
 					// ByteArrayOutputStream();
 					// FileOutputStream fos = new FileOutputStream(file);
-                                        
+
 					rawXML = embeddedFile.toByteArray();
 					setMeta(new String(rawXML));
 					extracted=true;
@@ -117,18 +108,7 @@ public class ZUGFeRDImporter {
 					// fos.close();
 				}
 			}
-
-		} catch (IOException e1) {
-			throw e1;
 		}
-		finally {
-			try {
-				if(doc!=null) {
-					doc.close();
-				}
-			} catch (IOException e) {}
-		}
-
 	}

 	public void parse() {
@@ -421,9 +401,9 @@ public class ZUGFeRDImporter {
 	public String getMeta() {
 		if (rawXML==null){
 			return null;
-		} else {
-			return new String(rawXML);
 		}
+
+		return new String(rawXML);
 	}


--- a/src/main/java/org/mustangproject/ZUGFeRD/model/ObjectFactory.java
+++ b/src/main/java/org/mustangproject/ZUGFeRD/model/ObjectFactory.java
@@ -1,8 +1,8 @@
 //
-// Diese Datei wurde mit der JavaTM Architecture for XML Binding(JAXB) Reference Implementation, v2.2.11 generiert 
-// Siehe <a href="http://java.sun.com/xml/jaxb">http://java.sun.com/xml/jaxb</a> 
-// <20>nderungen an dieser Datei gehen bei einer Neukompilierung des Quellschemas verloren. 
-// Generiert: 2015.10.16 um 06:16:03 PM CEST 
+// Diese Datei wurde mit der JavaTM Architecture for XML Binding(JAXB) Reference Implementation, v2.2.11 generiert
+// Siehe <a href="http://java.sun.com/xml/jaxb">http://java.sun.com/xml/jaxb</a>
+// <20>nderungen an dieser Datei gehen bei einer Neukompilierung des Quellschemas verloren.
+// Generiert: 2015.10.16 um 06:16:03 PM CEST
 //


@@ -11,23 +11,22 @@ package org.mustangproject.ZUGFeRD.model;
 import javax.xml.bind.JAXBElement;
 import javax.xml.bind.annotation.XmlElementDecl;
 import javax.xml.bind.annotation.XmlRegistry;
-import javax.xml.bind.annotation.XmlRootElement;
 import javax.xml.namespace.QName;


 /**
- * This object contains factory methods for each 
- * Java content interface and Java element interface 
- * generated in the org.mustangproject.ZUGFeRD.model package. 
- * <p>An ObjectFactory allows you to programatically 
- * construct new instances of the Java representation 
- * for XML content. The Java representation of XML 
- * content can consist of schema derived interfaces 
- * and classes representing the binding of schema 
- * type definitions, element declarations and model 
- * groups.  Factory methods for each of these are 
+ * This object contains factory methods for each
+ * Java content interface and Java element interface
+ * generated in the org.mustangproject.ZUGFeRD.model package.
+ * <p>An ObjectFactory allows you to programatically
+ * construct new instances of the Java representation
+ * for XML content. The Java representation of XML
+ * content can consist of schema derived interfaces
+ * and classes representing the binding of schema
+ * type definitions, element declarations and model
+ * groups.  Factory methods for each of these are
 * provided in this class.
- * 
+ *
 */
@XmlRegistry
 public class ObjectFactory {
@@ -36,14 +35,14 @@ public class ObjectFactory {

    /**
     * Create a new ObjectFactory that can be used to create new instances of schema derived classes for package: org.mustangproject.ZUGFeRD.model
-     * 
+     *
     */
    public ObjectFactory() {
    }

    /**
     * Create an instance of {@link DateTimeType }
-     * 
+     *
     */
    public DateTimeType createDateTimeType() {
        return new DateTimeType();
@@ -51,7 +50,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link CrossIndustryDocumentType }
-     * 
+     *
     */
    public CrossIndustryDocumentType createCrossIndustryDocumentType() {
        return new CrossIndustryDocumentType();
@@ -59,7 +58,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link AllowanceChargeReasonCodeType }
-     * 
+     *
     */
    public AllowanceChargeReasonCodeType createAllowanceChargeReasonCodeType() {
        return new AllowanceChargeReasonCodeType();
@@ -67,7 +66,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link CountryIDType }
-     * 
+     *
     */
    public CountryIDType createCountryIDType() {
        return new CountryIDType();
@@ -75,7 +74,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link DeliveryTermsCodeType }
-     * 
+     *
     */
    public DeliveryTermsCodeType createDeliveryTermsCodeType() {
        return new DeliveryTermsCodeType();
@@ -83,7 +82,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link DocumentCodeType }
-     * 
+     *
     */
    public DocumentCodeType createDocumentCodeType() {
        return new DocumentCodeType();
@@ -91,7 +90,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link PaymentMeansCodeType }
-     * 
+     *
     */
    public PaymentMeansCodeType createPaymentMeansCodeType() {
        return new PaymentMeansCodeType();
@@ -99,7 +98,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link ReferenceCodeType }
-     * 
+     *
     */
    public ReferenceCodeType createReferenceCodeType() {
        return new ReferenceCodeType();
@@ -107,7 +106,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TaxCategoryCodeType }
-     * 
+     *
     */
    public TaxCategoryCodeType createTaxCategoryCodeType() {
        return new TaxCategoryCodeType();
@@ -115,7 +114,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TaxTypeCodeType }
-     * 
+     *
     */
    public TaxTypeCodeType createTaxTypeCodeType() {
        return new TaxTypeCodeType();
@@ -123,7 +122,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link AmountType }
-     * 
+     *
     */
    public AmountType createAmountType() {
        return new AmountType();
@@ -131,7 +130,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link CodeType }
-     * 
+     *
     */
    public CodeType createCodeType() {
        return new CodeType();
@@ -139,7 +138,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link IDType }
-     * 
+     *
     */
    public IDType createIDType() {
        return new IDType();
@@ -147,7 +146,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link IndicatorType }
-     * 
+     *
     */
    public IndicatorType createIndicatorType() {
        return new IndicatorType();
@@ -155,7 +154,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link MeasureType }
-     * 
+     *
     */
    public MeasureType createMeasureType() {
        return new MeasureType();
@@ -163,7 +162,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link NumericType }
-     * 
+     *
     */
    public NumericType createNumericType() {
        return new NumericType();
@@ -171,7 +170,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link PercentType }
-     * 
+     *
     */
    public PercentType createPercentType() {
        return new PercentType();
@@ -179,7 +178,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link QuantityType }
-     * 
+     *
     */
    public QuantityType createQuantityType() {
        return new QuantityType();
@@ -187,7 +186,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TextType }
-     * 
+     *
     */
    public TextType createTextType() {
        return new TextType();
@@ -195,7 +194,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link CreditorFinancialAccountType }
-     * 
+     *
     */
    public CreditorFinancialAccountType createCreditorFinancialAccountType() {
        return new CreditorFinancialAccountType();
@@ -203,7 +202,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link CreditorFinancialInstitutionType }
-     * 
+     *
     */
    public CreditorFinancialInstitutionType createCreditorFinancialInstitutionType() {
        return new CreditorFinancialInstitutionType();
@@ -211,7 +210,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link DebtorFinancialAccountType }
-     * 
+     *
     */
    public DebtorFinancialAccountType createDebtorFinancialAccountType() {
        return new DebtorFinancialAccountType();
@@ -219,7 +218,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link DebtorFinancialInstitutionType }
-     * 
+     *
     */
    public DebtorFinancialInstitutionType createDebtorFinancialInstitutionType() {
        return new DebtorFinancialInstitutionType();
@@ -227,7 +226,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link DocumentContextParameterType }
-     * 
+     *
     */
    public DocumentContextParameterType createDocumentContextParameterType() {
        return new DocumentContextParameterType();
@@ -235,7 +234,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link DocumentLineDocumentType }
-     * 
+     *
     */
    public DocumentLineDocumentType createDocumentLineDocumentType() {
        return new DocumentLineDocumentType();
@@ -243,7 +242,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link ExchangedDocumentContextType }
-     * 
+     *
     */
    public ExchangedDocumentContextType createExchangedDocumentContextType() {
        return new ExchangedDocumentContextType();
@@ -251,7 +250,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link ExchangedDocumentType }
-     * 
+     *
     */
    public ExchangedDocumentType createExchangedDocumentType() {
        return new ExchangedDocumentType();
@@ -259,7 +258,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link LogisticsServiceChargeType }
-     * 
+     *
     */
    public LogisticsServiceChargeType createLogisticsServiceChargeType() {
        return new LogisticsServiceChargeType();
@@ -267,7 +266,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link LogisticsTransportMovementType }
-     * 
+     *
     */
    public LogisticsTransportMovementType createLogisticsTransportMovementType() {
        return new LogisticsTransportMovementType();
@@ -275,7 +274,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link NoteType }
-     * 
+     *
     */
    public NoteType createNoteType() {
        return new NoteType();
@@ -283,7 +282,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link ProductCharacteristicType }
-     * 
+     *
     */
    public ProductCharacteristicType createProductCharacteristicType() {
        return new ProductCharacteristicType();
@@ -291,7 +290,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link ProductClassificationType }
-     * 
+     *
     */
    public ProductClassificationType createProductClassificationType() {
        return new ProductClassificationType();
@@ -299,7 +298,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link ReferencedDocumentType }
-     * 
+     *
     */
    public ReferencedDocumentType createReferencedDocumentType() {
        return new ReferencedDocumentType();
@@ -307,7 +306,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link ReferencedProductType }
-     * 
+     *
     */
    public ReferencedProductType createReferencedProductType() {
        return new ReferencedProductType();
@@ -315,7 +314,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link SpecifiedPeriodType }
-     * 
+     *
     */
    public SpecifiedPeriodType createSpecifiedPeriodType() {
        return new SpecifiedPeriodType();
@@ -323,7 +322,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link SupplyChainConsignmentType }
-     * 
+     *
     */
    public SupplyChainConsignmentType createSupplyChainConsignmentType() {
        return new SupplyChainConsignmentType();
@@ -331,7 +330,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link SupplyChainEventType }
-     * 
+     *
     */
    public SupplyChainEventType createSupplyChainEventType() {
        return new SupplyChainEventType();
@@ -339,7 +338,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link SupplyChainTradeAgreementType }
-     * 
+     *
     */
    public SupplyChainTradeAgreementType createSupplyChainTradeAgreementType() {
        return new SupplyChainTradeAgreementType();
@@ -347,7 +346,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link SupplyChainTradeDeliveryType }
-     * 
+     *
     */
    public SupplyChainTradeDeliveryType createSupplyChainTradeDeliveryType() {
        return new SupplyChainTradeDeliveryType();
@@ -355,7 +354,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link SupplyChainTradeLineItemType }
-     * 
+     *
     */
    public SupplyChainTradeLineItemType createSupplyChainTradeLineItemType() {
        return new SupplyChainTradeLineItemType();
@@ -363,7 +362,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link SupplyChainTradeSettlementType }
-     * 
+     *
     */
    public SupplyChainTradeSettlementType createSupplyChainTradeSettlementType() {
        return new SupplyChainTradeSettlementType();
@@ -371,7 +370,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link SupplyChainTradeTransactionType }
-     * 
+     *
     */
    public SupplyChainTradeTransactionType createSupplyChainTradeTransactionType() {
        return new SupplyChainTradeTransactionType();
@@ -379,7 +378,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TaxRegistrationType }
-     * 
+     *
     */
    public TaxRegistrationType createTaxRegistrationType() {
        return new TaxRegistrationType();
@@ -387,7 +386,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradeAccountingAccountType }
-     * 
+     *
     */
    public TradeAccountingAccountType createTradeAccountingAccountType() {
        return new TradeAccountingAccountType();
@@ -395,7 +394,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradeAddressType }
-     * 
+     *
     */
    public TradeAddressType createTradeAddressType() {
        return new TradeAddressType();
@@ -403,7 +402,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradeAllowanceChargeType }
-     * 
+     *
     */
    public TradeAllowanceChargeType createTradeAllowanceChargeType() {
        return new TradeAllowanceChargeType();
@@ -411,7 +410,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradeContactType }
-     * 
+     *
     */
    public TradeContactType createTradeContactType() {
        return new TradeContactType();
@@ -419,7 +418,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradeCountryType }
-     * 
+     *
     */
    public TradeCountryType createTradeCountryType() {
        return new TradeCountryType();
@@ -427,7 +426,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradeDeliveryTermsType }
-     * 
+     *
     */
    public TradeDeliveryTermsType createTradeDeliveryTermsType() {
        return new TradeDeliveryTermsType();
@@ -435,7 +434,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradePartyType }
-     * 
+     *
     */
    public TradePartyType createTradePartyType() {
        return new TradePartyType();
@@ -443,7 +442,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradePaymentDiscountTermsType }
-     * 
+     *
     */
    public TradePaymentDiscountTermsType createTradePaymentDiscountTermsType() {
        return new TradePaymentDiscountTermsType();
@@ -451,7 +450,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradePaymentPenaltyTermsType }
-     * 
+     *
     */
    public TradePaymentPenaltyTermsType createTradePaymentPenaltyTermsType() {
        return new TradePaymentPenaltyTermsType();
@@ -459,7 +458,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradePaymentTermsType }
-     * 
+     *
     */
    public TradePaymentTermsType createTradePaymentTermsType() {
        return new TradePaymentTermsType();
@@ -467,7 +466,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradePriceType }
-     * 
+     *
     */
    public TradePriceType createTradePriceType() {
        return new TradePriceType();
@@ -475,7 +474,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradeProductType }
-     * 
+     *
     */
    public TradeProductType createTradeProductType() {
        return new TradeProductType();
@@ -483,7 +482,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradeSettlementMonetarySummationType }
-     * 
+     *
     */
    public TradeSettlementMonetarySummationType createTradeSettlementMonetarySummationType() {
        return new TradeSettlementMonetarySummationType();
@@ -491,7 +490,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradeSettlementPaymentMeansType }
-     * 
+     *
     */
    public TradeSettlementPaymentMeansType createTradeSettlementPaymentMeansType() {
        return new TradeSettlementPaymentMeansType();
@@ -499,7 +498,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link TradeTaxType }
-     * 
+     *
     */
    public TradeTaxType createTradeTaxType() {
        return new TradeTaxType();
@@ -507,7 +506,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link UniversalCommunicationType }
-     * 
+     *
     */
    public UniversalCommunicationType createUniversalCommunicationType() {
        return new UniversalCommunicationType();
@@ -515,7 +514,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link DateTimeType.DateTimeString }
-     * 
+     *
     */
    public DateTimeType.DateTimeString createDateTimeTypeDateTimeString() {
        return new DateTimeType.DateTimeString();
@@ -523,7 +522,7 @@ public class ObjectFactory {

    /**
     * Create an instance of {@link JAXBElement }{@code <}{@link CrossIndustryDocumentType }{@code >}}
-     * 
+     *
     */
    @XmlElementDecl(namespace = "urn:ferd:CrossIndustryDocument:invoice:1p0", name = "CrossIndustryDocument")
    public JAXBElement<CrossIndustryDocumentType> createCrossIndustryDocument(CrossIndustryDocumentType value) {
--- a/src/test/java/org/mustangproject/ZUGFeRD/MustangReaderWriterEdgeTest.java
+++ b/src/test/java/org/mustangproject/ZUGFeRD/MustangReaderWriterEdgeTest.java
@@ -401,27 +401,18 @@ public class MustangReaderWriterEdgeTest extends TestCase implements IZUGFeRDExp
  public void testZExport()
  {

-    final InputStream SOURCE_PDF = this.getClass().getResourceAsStream("/MustangGnuaccountingBeispielRE-20170509_505blanko.pdf");
-    final String TARGET_PDF = "./target/testout-MustangGnuaccountingBeispielRE-20170509_505newEdge.pdf";
-    // the writing part
+  	final String TARGET_PDF = "./target/testout-MustangGnuaccountingBeispielRE-20170509_505newEdge.pdf";

-    try
-    {
-      // automatically add Zugferd to all outgoing invoices
-      ZUGFeRDExporter ze = new ZUGFeRDExporter();
-      ze.PDFmakeA3compliant(SOURCE_PDF, "My Application", System.getProperty("user.name"), true);
-      ze.PDFattachZugferdFile(this);
-      ze.export(TARGET_PDF);
+	// the writing part
+    // automatically add Zugferd to all outgoing invoices
+	try (ZUGFeRDExporter ze = new ZUGFeRDExporter())	{
+		try(final InputStream SOURCE_PDF = this.getClass().getResourceAsStream("/MustangGnuaccountingBeispielRE-20170509_505blanko.pdf")){
+			ze.PDFmakeA3compliant(SOURCE_PDF, "My Application", System.getProperty("user.name"), true);
+		}
+        ze.PDFattachZugferdFile(this);
+        ze.export(TARGET_PDF);
    }
-    catch (IOException e)
-    {
-      e.printStackTrace();
-    }
-    catch (TransformerException e)
-    {
-      e.printStackTrace();
-    }
-    catch (Exception e)
+	catch (Exception e)
    {
      e.printStackTrace();
    }
--- a/src/test/java/org/mustangproject/ZUGFeRD/MustangReaderWriterTest.java
+++ b/src/test/java/org/mustangproject/ZUGFeRD/MustangReaderWriterTest.java
@@ -10,14 +10,13 @@ import java.util.GregorianCalendar;

 import javax.xml.transform.TransformerException;

+import org.junit.FixMethodOrder;
+import org.junit.runners.MethodSorters;
+
 import junit.framework.Test;
 import junit.framework.TestCase;
 import junit.framework.TestSuite;

-import org.apache.pdfbox.pdmodel.PDDocument;
-import org.junit.FixMethodOrder;
-import org.junit.runners.MethodSorters;
-
@FixMethodOrder(MethodSorters.NAME_ASCENDING)
 public class MustangReaderWriterTest extends TestCase implements IZUGFeRDExportableTransaction
 {
@@ -326,7 +325,7 @@ public class MustangReaderWriterTest extends TestCase implements IZUGFeRDExporta

    public void setVATPercent(BigDecimal VATPercent)
    {
-      VATPercent = VATPercent;
+    	this.VATPercent = VATPercent;
    }

  }
@@ -363,8 +362,10 @@ public class MustangReaderWriterTest extends TestCase implements IZUGFeRDExporta
  public void testAImport() throws IOException
  {
    ZUGFeRDImporter zi = new ZUGFeRDImporter();
-    InputStream inputStream = this.getClass().getResourceAsStream("/MustangGnuaccountingBeispielRE-20170509_505.pdf");
-    zi.extractLowLevel(inputStream);
+    try (InputStream inputStream = this.getClass().getResourceAsStream("/MustangGnuaccountingBeispielRE-20170509_505.pdf"))	{
+        zi.extractLowLevel(inputStream);
+    }
+
    // Reading ZUGFeRD

    String amount = null;
@@ -400,27 +401,19 @@ public class MustangReaderWriterTest extends TestCase implements IZUGFeRDExporta
   */
  public void testZExport()
  {
-    final InputStream SOURCE_PDF = this.getClass().getResourceAsStream("/MustangGnuaccountingBeispielRE-20170509_505blanko.pdf");
-    final String TARGET_PDF = "./target/testout-MustangGnuaccountingBeispielRE-20170509_505new.pdf";
+
+	final String TARGET_PDF = "./target/testout-MustangGnuaccountingBeispielRE-20170509_505new.pdf";

    // the writing part
-    try
-    {
-      // automatically add Zugferd to all outgoing invoices
-      ZUGFeRDExporter ze = new ZUGFeRDExporter();
-      ze.PDFmakeA3compliant(SOURCE_PDF, "My Application", System.getProperty("user.name"), true);
-      ze.PDFattachZugferdFile(this);
-      ze.export(TARGET_PDF);
+	// automatically add Zugferd to all outgoing invoices
+	try	(ZUGFeRDExporter ze = new ZUGFeRDExporter())	{
+		try	(final InputStream SOURCE_PDF = this.getClass().getResourceAsStream("/MustangGnuaccountingBeispielRE-20170509_505blanko.pdf"))	{
+			ze.PDFmakeA3compliant(SOURCE_PDF, "My Application", System.getProperty("user.name"), true);
+    	}
+        ze.PDFattachZugferdFile(this);
+        ze.export(TARGET_PDF);
    }
-    catch (IOException e)
-    {
-      e.printStackTrace();
-    }
-    catch (TransformerException e)
-    {
-      e.printStackTrace();
-    }
-    catch (Exception e)
+	catch (Exception e)
    {
      e.printStackTrace();
    }