Merge pull request #217 from weclapp-dev/dev/SellerOrderReferencedDocument

Dev/seller order referenced document

library/src/main/java/org/mustangproject/Invoice.java

@@ -39,6 +39,7 @@ public class Invoice implements IExportableTransaction {
 	protected TradeParty sender = null, recipient = null, deliveryAddress = null;
 	protected ArrayList<IZUGFeRDExportableItem> ZFItems = null;
 	protected ArrayList<String> notes = null;
+  private String sellerOrderReferencedDocumentID;
 	protected String contractReferencedDocument = null;
 	protected ArrayList<FileAttachment> xmlEmbeddedFiles=null;
 
@@ -50,7 +51,7 @@ public class Invoice implements IExportableTransaction {
 	protected IZUGFeRDPaymentTerms paymentTerms = null;
 
 
-	public Invoice() {
+  public Invoice() {
 		ZFItems = new ArrayList<IZUGFeRDExportableItem>();
 		setCurrency("EUR");
 	}
@@ -60,7 +61,8 @@ public class Invoice implements IExportableTransaction {
 		return documentName;
 	}
 
-	public String getContractReferencedDocument() {
+	@Override
+  public String getContractReferencedDocument() {
 		return contractReferencedDocument;
 	}
 
@@ -81,13 +83,14 @@ public class Invoice implements IExportableTransaction {
 
 	public Invoice embedFileInXML(FileAttachment fa) {
 		if (xmlEmbeddedFiles == null) {
-			xmlEmbeddedFiles=new ArrayList<FileAttachment>();
+			xmlEmbeddedFiles= new ArrayList<>();
 		}
 		xmlEmbeddedFiles.add(fa);
 		return this;
 	}
 
-	public FileAttachment[] getAdditionalReferencedDocuments() {
+	@Override
+  public FileAttachment[] getAdditionalReferencedDocuments() {
 		if (xmlEmbeddedFiles == null) {
 			return null;
 		}
@@ -209,7 +212,16 @@ public class Invoice implements IExportableTransaction {
 	public String getBuyerOrderReferencedDocumentID() {
 		return buyerOrderReferencedDocumentID;
 	}
+	@Override
+	public String getSellerOrderReferencedDocumentID() {
+		return sellerOrderReferencedDocumentID;
+	}
 
+
+  public Invoice setSellerOrderReferencedDocumentID(String sellerOrderReferencedDocumentID) {
+    this.sellerOrderReferencedDocumentID = sellerOrderReferencedDocumentID;
+    return this;
+  }
 	/***
 	 * usually the order number or in case of a correction the original invoice number
 	 * @param buyerOrderReferencedDocumentID string with number
@@ -310,12 +322,14 @@ public class Invoice implements IExportableTransaction {
 	}
 
 
-	public String getOwnLocation() {
+	@Override
+  public String getOwnLocation() {
 		return sender.getLocation();
 	}
 
 
-	public String getOwnCountry() {
+	@Override
+  public String getOwnCountry() {
 		return sender.getCountry();
 	}
 
@@ -405,7 +419,8 @@ public class Invoice implements IExportableTransaction {
 		return this;
 	}
 
-	public IZUGFeRDExportableTradeParty getRecipient() {
+	@Override
+  public IZUGFeRDExportableTradeParty getRecipient() {
 		return recipient;
 	}
 
@@ -439,8 +454,9 @@ public class Invoice implements IExportableTransaction {
 	public IZUGFeRDAllowanceCharge[] getZFAllowances() {
 		if (Allowances.isEmpty()) {
 			return null;
-		} else
+		} else {
-			return Allowances.toArray(new IZUGFeRDAllowanceCharge[0]);
+      return Allowances.toArray(new IZUGFeRDAllowanceCharge[0]);
+    }
 	}
 
 
@@ -448,8 +464,9 @@ public class Invoice implements IExportableTransaction {
 	public IZUGFeRDAllowanceCharge[] getZFCharges() {
 		if (Charges.isEmpty()) {
 			return null;
-		} else
+		} else {
-			return Charges.toArray(new IZUGFeRDAllowanceCharge[0]);
+      return Charges.toArray(new IZUGFeRDAllowanceCharge[0]);
+    }
 	}
 
 
@@ -457,8 +474,9 @@ public class Invoice implements IExportableTransaction {
 	public IZUGFeRDAllowanceCharge[] getZFLogisticsServiceCharges() {
 		if (LogisticsServiceCharges.isEmpty()) {
 			return null;
-		} else
+		} else {
-			return LogisticsServiceCharges.toArray(new IZUGFeRDAllowanceCharge[0]);
+      return LogisticsServiceCharges.toArray(new IZUGFeRDAllowanceCharge[0]);
+    }
 	}
 
 
@@ -599,7 +617,7 @@ public class Invoice implements IExportableTransaction {
 	 */
 	public Invoice addNote(String text) {
 		if (notes == null) {
-			notes = new ArrayList<String>();
+			notes = new ArrayList<>();
 		}
 		notes.add(text);
 		return this;

library/src/main/java/org/mustangproject/ZUGFeRD/IExportableTransaction.java

@@ -398,6 +398,14 @@ public interface IExportableTransaction  {
 	}
 
 
+	/**
+	 * get the ID of the SellerOrderReferencedDocument, which sits in the ApplicableSupplyChainTradeAgreement/ApplicableHeaderTradeAgreement
+	 *
+	 * @return the ID of the document
+	 */
+	default String getSellerOrderReferencedDocumentID() {
+		return null;
+	}
 	/**
 	 * get the ID of the BuyerOrderReferencedDocument, which sits in the ApplicableSupplyChainTradeAgreement
 	 *

library/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRD1PullProvider.java

@@ -20,13 +20,6 @@
  */
 package org.mustangproject.ZUGFeRD;
 
-import org.dom4j.Document;
-import org.dom4j.DocumentException;
-import org.dom4j.DocumentHelper;
-import org.dom4j.io.OutputFormat;
-import org.dom4j.io.XMLWriter;
-import org.mustangproject.XMLTools;
-
 import java.io.IOException;
 import java.io.StringWriter;
 import java.io.UnsupportedEncodingException;
@@ -37,6 +30,13 @@ import java.util.HashMap;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
+import org.dom4j.Document;
+import org.dom4j.DocumentException;
+import org.dom4j.DocumentHelper;
+import org.dom4j.io.OutputFormat;
+import org.dom4j.io.XMLWriter;
+import org.mustangproject.XMLTools;
+
 public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLProvider {
 
 
@@ -82,20 +82,20 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 
 		byte[] res = zugferdData;
 
-		StringWriter sw = new StringWriter();
+		final StringWriter sw = new StringWriter();
 		Document document = null;
 		try {
 			document = DocumentHelper.parseText(new String(zugferdData));
-		} catch (DocumentException e1) {
+		} catch (final DocumentException e1) {
 			Logger.getLogger(ZUGFeRD1PullProvider.class.getName()).log(Level.SEVERE, null, e1);
 		}
 		try {
-			OutputFormat format = OutputFormat.createPrettyPrint();
+			final OutputFormat format = OutputFormat.createPrettyPrint();
-			XMLWriter writer = new XMLWriter(sw, format);
+			final XMLWriter writer = new XMLWriter(sw, format);
 			writer.write(document);
 			res = sw.toString().getBytes("UTF-8");
 
-		} catch (IOException e) {
+		} catch (final IOException e) {
 			Logger.getLogger(ZUGFeRD1PullProvider.class.getName()).log(Level.SEVERE, null, e);
 		}
 
@@ -110,7 +110,7 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 		this.calc = new TransactionCalculator(trans);
 
 		boolean hasDueDate = false;
-		SimpleDateFormat germanDateFormat = new SimpleDateFormat("dd.MM.yyyy");
+		final SimpleDateFormat germanDateFormat = new SimpleDateFormat("dd.MM.yyyy");
 		String exemptionReason = "";
 
 		if (trans.getPaymentTermDescription() != null) {
@@ -199,6 +199,12 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 
 		xml += "			</ram:BuyerTradeParty>\n";
 
+		if (trans.getSellerOrderReferencedDocumentID() != null) {
+			xml = xml + "   <ram:SellerOrderReferencedDocument>\n"
+					+ "       <ram:IssuerAssignedID>"
+					+ XMLTools.encodeXML(trans.getSellerOrderReferencedDocumentID()) + "</ram:IssuerAssignedID>\n"
+					+ "   </ram:SellerOrderReferencedDocument>\n";
+		}
 		if (trans.getBuyerOrderReferencedDocumentID() != null) {
 			xml = xml + "   <ram:BuyerOrderReferencedDocument>\n"
 					+ "       <ram:IssuerAssignedID>"
@@ -235,7 +241,7 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 				+ "			<ram:InvoiceCurrencyCode>" + trans.getCurrency() + "</ram:InvoiceCurrencyCode>\n";
 
 		if (trans.getTradeSettlementPayment() != null) {
-			for (IZUGFeRDTradeSettlementPayment payment : trans.getTradeSettlementPayment()) {
+			for (final IZUGFeRDTradeSettlementPayment payment : trans.getTradeSettlementPayment()) {
 				if (payment != null) {
 					hasDueDate = true;
 					xml += payment.getSettlementXML();
@@ -243,7 +249,7 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 			}
 		}
 		if (trans.getTradeSettlement() != null) {
-			for (IZUGFeRDTradeSettlement payment : trans.getTradeSettlement()) {
+			for (final IZUGFeRDTradeSettlement payment : trans.getTradeSettlement()) {
 				if (payment != null) {
 					if (payment instanceof IZUGFeRDTradeSettlementPayment) {
 						hasDueDate = true;
@@ -253,9 +259,9 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 			}
 		}
 
-		HashMap<BigDecimal, VATAmount> VATPercentAmountMap = calc.getVATPercentAmountMap();
+		final HashMap<BigDecimal, VATAmount> VATPercentAmountMap = calc.getVATPercentAmountMap();
-		for (BigDecimal currentTaxPercent : VATPercentAmountMap.keySet()) {
+		for (final BigDecimal currentTaxPercent : VATPercentAmountMap.keySet()) {
-			VATAmount amount = VATPercentAmountMap.get(currentTaxPercent);
+			final VATAmount amount = VATPercentAmountMap.get(currentTaxPercent);
 			if (amount != null) {
 				xml += "			<ram:ApplicableTradeTax>\n"
 						+ "				<ram:CalculatedAmount currencyID=\"" + trans.getCurrency() + "\">" + currencyFormat(amount.getCalculated())
@@ -275,7 +281,7 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 					+ "				<ram:Description>" + paymentTermsDescription + "</ram:Description>\n";
 
 			if (trans.getTradeSettlement() != null) {
-				for (IZUGFeRDTradeSettlement payment : trans.getTradeSettlement()) {
+				for (final IZUGFeRDTradeSettlement payment : trans.getTradeSettlement()) {
 					if ((payment != null) && (payment instanceof IZUGFeRDTradeSettlementDebit)) {
 						xml += payment.getPaymentXML();
 					}
@@ -318,14 +324,14 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 
 
 		int lineID = 0;
-		for (IZUGFeRDExportableItem currentItem : trans.getZFItems()) {
+		for (final IZUGFeRDExportableItem currentItem : trans.getZFItems()) {
 			lineID++;
 			if (currentItem.getProduct().getTaxExemptionReason() != null) {
 				exemptionReason = "<ram:ExemptionReason>" + XMLTools.encodeXML(currentItem.getProduct().getTaxExemptionReason()) + "</ram:ExemptionReason>";
 			}
 
 
-			LineCalculator lc = new LineCalculator(currentItem);
+			final LineCalculator lc = new LineCalculator(currentItem);
 			xml = xml + "		<ram:IncludedSupplyChainTradeLineItem>\n" +
 					"			<ram:AssociatedDocumentLineDocument>\n"
 					+ "				<ram:LineID>" + lineID + "</ram:LineID>\n" //$NON-NLS-2$
@@ -404,11 +410,11 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 		xml = xml + "	</rsm:SpecifiedSupplyChainTradeTransaction>\n"
 				+ "</rsm:CrossIndustryDocument>";
 
-		byte[] zugferdRaw;
+		final byte[] zugferdRaw;
 		try {
 			zugferdRaw = xml.getBytes("UTF-8");
 			zugferdData = XMLTools.removeBOM(zugferdRaw);
-		} catch (UnsupportedEncodingException e) {
+		} catch (final UnsupportedEncodingException e) {
 			Logger.getLogger(ZUGFeRD1PullProvider.class.getName()).log(Level.SEVERE, null, e);
 		}
 	}
@@ -421,9 +427,9 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 	private String buildPaymentTermsXml() {
 		String paymentTermsXml = "<ram:SpecifiedTradePaymentTerms>";
 
-		IZUGFeRDPaymentTerms paymentTerms = trans.getPaymentTerms();
+		final IZUGFeRDPaymentTerms paymentTerms = trans.getPaymentTerms();
-		IZUGFeRDPaymentDiscountTerms discountTerms = paymentTerms.getDiscountTerms();
+		final IZUGFeRDPaymentDiscountTerms discountTerms = paymentTerms.getDiscountTerms();
-		Date dueDate = paymentTerms.getDueDate();
+		final Date dueDate = paymentTerms.getDueDate();
 		if (dueDate != null && discountTerms != null && discountTerms.getBaseDate() != null) {
 			throw new IllegalStateException(
 					"if paymentTerms.dueDate is specified, paymentTerms.discountTerms.baseDate has not to be specified");
@@ -438,14 +444,14 @@ public class ZUGFeRD1PullProvider extends ZUGFeRD2PullProvider implements IXMLPr
 
 		if (discountTerms != null) {
 			paymentTermsXml += "<ram:ApplicableTradePaymentDiscountTerms>";
-			String currency = trans.getCurrency();
+			final String currency = trans.getCurrency();
-			String basisAmount = currencyFormat(calc.getGrandTotal());
+			final String basisAmount = currencyFormat(calc.getGrandTotal());
 			paymentTermsXml += "<ram:BasisAmount currencyID=\"" + currency + "\">" + basisAmount + "</ram:BasisAmount>";
 			paymentTermsXml += "<ram:CalculationPercent>" + discountTerms.getCalculationPercentage().toString()
 					+ "</ram:CalculationPercent>";
 
 			if (discountTerms.getBaseDate() != null) {
-				Date baseDate = discountTerms.getBaseDate();
+				final Date baseDate = discountTerms.getBaseDate();
 				paymentTermsXml += "<ram:BasisDateTime>";
 				paymentTermsXml += "<udt:DateTimeString format=\"102\">" + zugferdDateFormat.format(baseDate) + "</udt:DateTimeString>";
 				paymentTermsXml += "</ram:BasisDateTime>";

library/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRD2PullProvider.java

@@ -20,17 +20,18 @@
  */
 package org.mustangproject.ZUGFeRD;
 
+import static org.mustangproject.ZUGFeRD.model.DocumentCodeTypeConstants.CORRECTEDINVOICE;
+
 import java.io.IOException;
 import java.io.StringWriter;
 import java.io.UnsupportedEncodingException;
 import java.math.BigDecimal;
-import java.math.RoundingMode;
 import java.text.SimpleDateFormat;
+import java.util.Base64;
 import java.util.Date;
 import java.util.HashMap;
 import java.util.logging.Level;
 import java.util.logging.Logger;
-import java.util.Base64;
 
 import org.dom4j.Document;
 import org.dom4j.DocumentException;
@@ -39,9 +40,6 @@ import org.dom4j.io.OutputFormat;
 import org.dom4j.io.XMLWriter;
 import org.mustangproject.FileAttachment;
 import org.mustangproject.XMLTools;
-import org.mustangproject.ZUGFeRD.model.DocumentCodeTypeConstants;
-
-import static org.mustangproject.ZUGFeRD.model.DocumentCodeTypeConstants.CORRECTEDINVOICE;
 
 public class ZUGFeRD2PullProvider implements IXMLProvider {
 
@@ -82,20 +80,20 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 
 		byte[] res = zugferdData;
 
-		StringWriter sw = new StringWriter();
+		final StringWriter sw = new StringWriter();
 		Document document = null;
 		try {
 			document = DocumentHelper.parseText(new String(zugferdData));
-		} catch (DocumentException e1) {
+		} catch (final DocumentException e1) {
 			Logger.getLogger(ZUGFeRD2PullProvider.class.getName()).log(Level.SEVERE, null, e1);
 		}
 		try {
-			OutputFormat format = OutputFormat.createPrettyPrint();
+			final OutputFormat format = OutputFormat.createPrettyPrint();
-			XMLWriter writer = new XMLWriter(sw, format);
+			final XMLWriter writer = new XMLWriter(sw, format);
 			writer.write(document);
 			res = sw.toString().getBytes("UTF-8");
 
-		} catch (IOException e) {
+		} catch (final IOException e) {
 			Logger.getLogger(ZUGFeRD2PullProvider.class.getName()).log(Level.SEVERE, null, e);
 		}
 
@@ -210,7 +208,7 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 			// only in extended profile
 			reason = "<ram:Reason>" + XMLTools.encodeXML(allowance.getReason()) + "</ram:Reason>";
 		}
-		String allowanceChargeStr = "<ram:AppliedTradeAllowanceCharge><ram:ChargeIndicator><udt:Indicator>" +
+		final String allowanceChargeStr = "<ram:AppliedTradeAllowanceCharge><ram:ChargeIndicator><udt:Indicator>" +
 				chargeIndicator + "</udt:Indicator></ram:ChargeIndicator>" + percentage +
 				"<ram:ActualAmount>" + priceFormat(allowance.getTotalAmount(item)) + "</ram:ActualAmount>" +
 				reason +
@@ -224,7 +222,7 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 		this.calc = new TransactionCalculator(trans);
 
 		boolean hasDueDate = false;
-		SimpleDateFormat germanDateFormat = new SimpleDateFormat("dd.MM.yyyy");
+		final SimpleDateFormat germanDateFormat = new SimpleDateFormat("dd.MM.yyyy");
 
 		String exemptionReason = "";
 
@@ -265,7 +263,7 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 		}
 		String notes = "";
 		if (trans.getNotes() != null) {
-			for (String currentNote : trans.getNotes()) {
+			for (final String currentNote : trans.getNotes()) {
 				notes = notes + "<ram:IncludedNote><ram:Content>" + XMLTools.encodeXML(currentNote) + "</ram:Content></ram:IncludedNote>";
 
 			}
@@ -301,19 +299,19 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 				+ "	</rsm:ExchangedDocument>\n"
 				+ "	<rsm:SupplyChainTradeTransaction>\n";
 		int lineID = 0;
-		for (IZUGFeRDExportableItem currentItem : trans.getZFItems()) {
+		for (final IZUGFeRDExportableItem currentItem : trans.getZFItems()) {
 			lineID++;
 			if (currentItem.getProduct().getTaxExemptionReason() != null) {
 				exemptionReason = "<ram:ExemptionReason>" + XMLTools.encodeXML(currentItem.getProduct().getTaxExemptionReason()) + "</ram:ExemptionReason>";
 			}
 			notes = "";
 			if (currentItem.getNotes() != null) {
-				for (String currentNote : currentItem.getNotes()) {
+				for (final String currentNote : currentItem.getNotes()) {
 					notes = notes + "<ram:IncludedNote><ram:Content>" + XMLTools.encodeXML(currentNote) + "</ram:Content></ram:IncludedNote>";
 
 				}
 			}
-			LineCalculator lc = new LineCalculator(currentItem);
+			final LineCalculator lc = new LineCalculator(currentItem);
 			xml = xml + "		<ram:IncludedSupplyChainTradeLineItem>\n" +
 					"			<ram:AssociatedDocumentLineDocument>\n"
 					+ "				<ram:LineID>" + lineID + "</ram:LineID>\n" //$NON-NLS-2$
@@ -332,12 +330,12 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 			}
 			String allowanceChargeStr = "";
 			if (currentItem.getItemAllowances() != null && currentItem.getItemAllowances().length > 0) {
-				for (IZUGFeRDAllowanceCharge allowance : currentItem.getItemAllowances()) {
+				for (final IZUGFeRDAllowanceCharge allowance : currentItem.getItemAllowances()) {
 					allowanceChargeStr += getAllowanceChargeStr(allowance, currentItem);
 				}
 			}
 			if (currentItem.getItemCharges() != null && currentItem.getItemCharges().length > 0) {
-				for (IZUGFeRDAllowanceCharge charge : currentItem.getItemCharges()) {
+				for (final IZUGFeRDAllowanceCharge charge : currentItem.getItemCharges()) {
 					allowanceChargeStr += getAllowanceChargeStr(charge, currentItem);
 
 				}
@@ -423,6 +421,12 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 		xml += getTradePartyAsXML(trans.getRecipient(), false, false);
 		xml += "			</ram:BuyerTradeParty>\n";
 
+		if (trans.getSellerOrderReferencedDocumentID() != null) {
+			xml = xml + "   <ram:SellerOrderReferencedDocument>\n"
+					+ "       <ram:IssuerAssignedID>"
+					+ XMLTools.encodeXML(trans.getSellerOrderReferencedDocumentID()) + "</ram:IssuerAssignedID>\n"
+					+ "   </ram:SellerOrderReferencedDocument>\n";
+		}
 		if (trans.getBuyerOrderReferencedDocumentID() != null) {
 			xml = xml + "   <ram:BuyerOrderReferencedDocument>\n"
 					+ "       <ram:IssuerAssignedID>"
@@ -438,7 +442,7 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 
 		// Additional Documents of XRechnung (Rechnungsbegruendende Unterlagen - BG-24 XRechnung)
 		if (trans.getAdditionalReferencedDocuments() != null) {
-			for (FileAttachment f : trans.getAdditionalReferencedDocuments()) {
+			for (final FileAttachment f : trans.getAdditionalReferencedDocuments()) {
 				final String documentContent = new String(Base64.getEncoder().encodeToString(f.getData()));
 				xml = xml + "  <ram:AdditionalReferencedDocument>\n"
 						+ "    <ram:IssuerAssignedID>" + f.getFilename() + "</ram:IssuerAssignedID>\n"
@@ -480,7 +484,7 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 				+ "			<ram:InvoiceCurrencyCode>" + trans.getCurrency() + "</ram:InvoiceCurrencyCode>\n";
 
 		if (trans.getTradeSettlementPayment() != null) {
-			for (IZUGFeRDTradeSettlementPayment payment : trans.getTradeSettlementPayment()) {
+			for (final IZUGFeRDTradeSettlementPayment payment : trans.getTradeSettlementPayment()) {
 				if (payment != null) {
 					hasDueDate = true;
 					xml += payment.getSettlementXML();
@@ -488,7 +492,7 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 			}
 		}
 		if (trans.getTradeSettlement() != null) {
-			for (IZUGFeRDTradeSettlement payment : trans.getTradeSettlement()) {
+			for (final IZUGFeRDTradeSettlement payment : trans.getTradeSettlement()) {
 				if (payment != null) {
 					if (payment instanceof IZUGFeRDTradeSettlementPayment) {
 						hasDueDate = true;
@@ -501,9 +505,9 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 			hasDueDate = false;
 		}
 
-		HashMap<BigDecimal, VATAmount> VATPercentAmountMap = calc.getVATPercentAmountMap();
+		final HashMap<BigDecimal, VATAmount> VATPercentAmountMap = calc.getVATPercentAmountMap();
-		for (BigDecimal currentTaxPercent : VATPercentAmountMap.keySet()) {
+		for (final BigDecimal currentTaxPercent : VATPercentAmountMap.keySet()) {
-			VATAmount amount = VATPercentAmountMap.get(currentTaxPercent);
+			final VATAmount amount = VATPercentAmountMap.get(currentTaxPercent);
 			if (amount != null) {
 				xml += "			<ram:ApplicableTradeTax>\n"
 						+ "				<ram:CalculatedAmount>" + currencyFormat(amount.getCalculated())
@@ -532,7 +536,7 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 
 		if ((trans.getZFCharges() != null) && (trans.getZFCharges().length > 0)) {
 
-			for (BigDecimal currentTaxPercent : VATPercentAmountMap.keySet()) {
+			for (final BigDecimal currentTaxPercent : VATPercentAmountMap.keySet()) {
 				if (calc.getChargesForPercent(currentTaxPercent).compareTo(BigDecimal.ZERO) != 0) {
 
 
@@ -555,7 +559,7 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 		}
 
 		if ((trans.getZFAllowances() != null) && (trans.getZFAllowances().length > 0)) {
-			for (BigDecimal currentTaxPercent : VATPercentAmountMap.keySet()) {
+			for (final BigDecimal currentTaxPercent : VATPercentAmountMap.keySet()) {
 				if (calc.getAllowancesForPercent(currentTaxPercent).compareTo(BigDecimal.ZERO) != 0) {
 					xml = xml + "	 <ram:SpecifiedTradeAllowanceCharge>\n" +
 							"        <ram:ChargeIndicator>\n" +
@@ -582,7 +586,7 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 			}
 
 			if (trans.getTradeSettlement() != null) {
-				for (IZUGFeRDTradeSettlement payment : trans.getTradeSettlement()) {
+				for (final IZUGFeRDTradeSettlement payment : trans.getTradeSettlement()) {
 					if ((payment != null) && (payment instanceof IZUGFeRDTradeSettlementDebit)) {
 						xml += payment.getPaymentXML();
 					}
@@ -601,9 +605,9 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 		}
 
 
-		String allowanceTotalLine = "<ram:AllowanceTotalAmount>" + currencyFormat(calc.getAllowancesForPercent(null)) + "</ram:AllowanceTotalAmount>";
+		final String allowanceTotalLine = "<ram:AllowanceTotalAmount>" + currencyFormat(calc.getAllowancesForPercent(null)) + "</ram:AllowanceTotalAmount>";
 
-		String chargesTotalLine = "<ram:ChargeTotalAmount>" + currencyFormat(calc.getChargesForPercent(null)) + "</ram:ChargeTotalAmount>";
+		final String chargesTotalLine = "<ram:ChargeTotalAmount>" + currencyFormat(calc.getChargesForPercent(null)) + "</ram:ChargeTotalAmount>";
 
 		xml = xml + "			<ram:SpecifiedTradeSettlementHeaderMonetarySummation>\n"
 				+ "				<ram:LineTotalAmount>" + currencyFormat(calc.getTotal()) + "</ram:LineTotalAmount>\n" //$NON-NLS-2$
@@ -635,12 +639,12 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 		xml = xml + "	</rsm:SupplyChainTradeTransaction>\n"
 				+ "</rsm:CrossIndustryInvoice>";
 
-		byte[] zugferdRaw;
+		final byte[] zugferdRaw;
 		try {
 			zugferdRaw = xml.getBytes("UTF-8");
 
 			zugferdData = XMLTools.removeBOM(zugferdRaw);
-		} catch (UnsupportedEncodingException e) {
+		} catch (final UnsupportedEncodingException e) {
 			Logger.getLogger(ZUGFeRD2PullProvider.class.getName()).log(Level.SEVERE, null, e);
 		}
 	}
@@ -652,14 +656,14 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 
 	private String buildPaymentTermsXml() {
 
-		IZUGFeRDPaymentTerms paymentTerms = trans.getPaymentTerms();
+		final IZUGFeRDPaymentTerms paymentTerms = trans.getPaymentTerms();
 		if (paymentTerms==null) {
 			return "";
 		}
 		String paymentTermsXml = "<ram:SpecifiedTradePaymentTerms>";
 
-		IZUGFeRDPaymentDiscountTerms discountTerms = paymentTerms.getDiscountTerms();
+		final IZUGFeRDPaymentDiscountTerms discountTerms = paymentTerms.getDiscountTerms();
-		Date dueDate = paymentTerms.getDueDate();
+		final Date dueDate = paymentTerms.getDueDate();
 		if (dueDate != null && discountTerms != null && discountTerms.getBaseDate() != null) {
 			throw new IllegalStateException(
 					"if paymentTerms.dueDate is specified, paymentTerms.discountTerms.baseDate has not to be specified");
@@ -674,14 +678,14 @@ public class ZUGFeRD2PullProvider implements IXMLProvider {
 
 		if (discountTerms != null) {
 			paymentTermsXml += "<ram:ApplicableTradePaymentDiscountTerms>";
-			String currency = trans.getCurrency();
+			final String currency = trans.getCurrency();
-			String basisAmount = currencyFormat(calc.getGrandTotal());
+			final String basisAmount = currencyFormat(calc.getGrandTotal());
 			paymentTermsXml += "<ram:BasisAmount currencyID=\"" + currency + "\">" + basisAmount + "</ram:BasisAmount>";
 			paymentTermsXml += "<ram:CalculationPercent>" + discountTerms.getCalculationPercentage().toString()
 					+ "</ram:CalculationPercent>";
 
 			if (discountTerms.getBaseDate() != null) {
-				Date baseDate = discountTerms.getBaseDate();
+				final Date baseDate = discountTerms.getBaseDate();
 				paymentTermsXml += "<ram:BasisDateTime>";
 				paymentTermsXml += "<udt:DateTimeString format=\"102\">" + zugferdDateFormat.format(baseDate) + "</udt:DateTimeString>";
 				paymentTermsXml += "</ram:BasisDateTime>";

library/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDImporter.java

@@ -21,23 +21,31 @@ import java.math.BigDecimal;
 import java.nio.file.Files;
 import java.nio.file.Paths;
 import java.nio.file.StandardOpenOption;
-import java.util.*;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.Scanner;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
 import javax.xml.parsers.DocumentBuilder;
 import javax.xml.parsers.DocumentBuilderFactory;
 import javax.xml.parsers.ParserConfigurationException;
-import javax.xml.xpath.*;
+import javax.xml.xpath.XPath;
+import javax.xml.xpath.XPathConstants;
+import javax.xml.xpath.XPathExpression;
+import javax.xml.xpath.XPathExpressionException;
+import javax.xml.xpath.XPathFactory;
 
-import org.mustangproject.Item;
-import org.mustangproject.Product;
 import org.apache.pdfbox.pdmodel.PDDocument;
 import org.apache.pdfbox.pdmodel.PDDocumentNameDictionary;
 import org.apache.pdfbox.pdmodel.PDEmbeddedFilesNameTreeNode;
 import org.apache.pdfbox.pdmodel.common.PDNameTreeNode;
 import org.apache.pdfbox.pdmodel.common.filespecification.PDComplexFileSpecification;
 import org.apache.pdfbox.pdmodel.common.filespecification.PDEmbeddedFile;
+import org.mustangproject.Item;
+import org.mustangproject.Product;
 import org.w3c.dom.Document;
 import org.w3c.dom.Node;
 import org.w3c.dom.NodeList;
@@ -74,7 +82,7 @@ public class ZUGFeRDImporter {
 	public ZUGFeRDImporter(String pdfFilename) {
 		try (InputStream bis = Files.newInputStream(Paths.get(pdfFilename), StandardOpenOption.READ)) {
 			extractLowLevel(bis);
-		} catch (IOException e) {
+		} catch (final IOException e) {
 			Logger.getLogger(ZUGFeRDImporter.class.getName()).log(Level.SEVERE, null, e);
 			throw new ZUGFeRDExportException(e);
 		}
@@ -84,7 +92,7 @@ public class ZUGFeRDImporter {
 	public ZUGFeRDImporter(InputStream pdfStream) {
 		try {
 			extractLowLevel(pdfStream);
-		} catch (IOException e) {
+		} catch (final IOException e) {
 			Logger.getLogger(ZUGFeRDImporter.class.getName()).log(Level.SEVERE, null, e);
 			throw new ZUGFeRDExportException(e);
 		}
@@ -99,7 +107,7 @@ public class ZUGFeRDImporter {
 	private void extractLowLevel(InputStream pdfStream) throws IOException {
 		try (PDDocument doc = PDDocument.load(pdfStream)) {
 			// PDDocumentInformation info = doc.getDocumentInformation();
-			PDDocumentNameDictionary names = new PDDocumentNameDictionary(doc.getDocumentCatalog());
+			final PDDocumentNameDictionary names = new PDDocumentNameDictionary(doc.getDocumentCatalog());
 			//start
 
 			if (doc.getDocumentCatalog() == null || doc.getDocumentCatalog().getMetadata() == null) {
@@ -107,15 +115,15 @@ public class ZUGFeRDImporter {
 				return;
 			}
 
-			InputStream XMP = doc.getDocumentCatalog().getMetadata().exportXMPMetadata();
+			final InputStream XMP = doc.getDocumentCatalog().getMetadata().exportXMPMetadata();
 			xmpString = convertStreamToString(XMP);
 
-			PDEmbeddedFilesNameTreeNode etn = names.getEmbeddedFiles();
+			final PDEmbeddedFilesNameTreeNode etn = names.getEmbeddedFiles();
 			if (etn == null) {
 				return;
 			}
 
-			Map<String, PDComplexFileSpecification> efMap = etn.getNames();
+			final Map<String, PDComplexFileSpecification> efMap = etn.getNames();
 			// String filePath = "/tmp/";
 
 			if (efMap != null) {
@@ -123,9 +131,9 @@ public class ZUGFeRDImporter {
 				// https://memorynotfound.com/apache-pdfbox-extract-embedded-file-pdf-document/
 			} else {
 
-				List<PDNameTreeNode<PDComplexFileSpecification>> kids = etn.getKids();
+				final List<PDNameTreeNode<PDComplexFileSpecification>> kids = etn.getKids();
-				for (PDNameTreeNode<PDComplexFileSpecification> node : kids) {
+				for (final PDNameTreeNode<PDComplexFileSpecification> node : kids) {
-					Map<String, PDComplexFileSpecification> namesL = node.getNames();
+					final Map<String, PDComplexFileSpecification> namesL = node.getNames();
 					extractFiles(namesL);
 				}
 			}
@@ -134,17 +142,17 @@ public class ZUGFeRDImporter {
 
 
 	private void extractFiles(Map<String, PDComplexFileSpecification> names) throws IOException {
-		for (String alias : names.keySet()) {
+		for (final String alias : names.keySet()) {
 
-			PDComplexFileSpecification fileSpec = names.get(alias);
+			final PDComplexFileSpecification fileSpec = names.get(alias);
-			String filename = fileSpec.getFilename();
+			final String filename = fileSpec.getFilename();
 			/**
 			 * filenames for invoice data (ZUGFeRD v1 and v2, Factur-X)
 			 */
 			if ((filename.equals("ZUGFeRD-invoice.xml") || (filename.equals("zugferd-invoice.xml")) || filename.equals("factur-x.xml")) || filename.equals("xrechnung.xml") || filename.equals("order-x.xml")) {
 				containsMeta = true;
 
-				PDEmbeddedFile embeddedFile = fileSpec.getEmbeddedFile();
+				final PDEmbeddedFile embeddedFile = fileSpec.getEmbeddedFile();
 				// String embeddedFilename = filePath + filename;
 				// File file = new File(filePath + filename);
 				// System.out.println("Writing " + embeddedFilename);
@@ -158,7 +166,7 @@ public class ZUGFeRDImporter {
 				// fos.close();
 			}
 			if (filename.startsWith("additional_data")) {
-				PDEmbeddedFile embeddedFile = fileSpec.getEmbeddedFile();
+				final PDEmbeddedFile embeddedFile = fileSpec.getEmbeddedFile();
 				additionalXMLs.put(filename, embeddedFile.toByteArray());
 			}
 		}
@@ -171,10 +179,10 @@ public class ZUGFeRDImporter {
 
 
 	private void setDocument() throws ParserConfigurationException, IOException, SAXException {
-		DocumentBuilderFactory xmlFact = DocumentBuilderFactory.newInstance();
+		final DocumentBuilderFactory xmlFact = DocumentBuilderFactory.newInstance();
 		xmlFact.setNamespaceAware(false);
-		DocumentBuilder builder = xmlFact.newDocumentBuilder();
+		final DocumentBuilder builder = xmlFact.newDocumentBuilder();
-		ByteArrayInputStream is = new ByteArrayInputStream(rawXML);
+		final ByteArrayInputStream is = new ByteArrayInputStream(rawXML);
 	///	is.skip(guessBOMSize(is));
 		document = builder.parse(is);
 	}
@@ -197,13 +205,13 @@ public class ZUGFeRDImporter {
 		if (!containsMeta) {
 			throw new ZUGFeRDExportException("No suitable data/ZUGFeRD file could be found.");
 		}
-		String result;
+		final String result;
 		try {
-			Document document = getDocument();
+			final Document document = getDocument();
-			XPathFactory xpathFact = XPathFactory.newInstance();
+			final XPathFactory xpathFact = XPathFactory.newInstance();
-			XPath xpath = xpathFact.newXPath();
+			final XPath xpath = xpathFact.newXPath();
 			result = xpath.evaluate(xpathStr, document);
-		} catch (XPathExpressionException e) {
+		} catch (final XPathExpressionException e) {
 			Logger.getLogger(ZUGFeRDImporter.class.getName()).log(Level.SEVERE, null, e);
 			throw new ZUGFeRDExportException(e);
 		}
@@ -263,7 +271,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//ApplicableHeaderTradeSettlement//InvoiceCurrencyCode");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -273,13 +281,31 @@ public class ZUGFeRDImporter {
 	 * @return the IssuerAssigned ID
 	 */
 	public String getIssuerAssignedID() {
+		return extractIssuerAssignedID("BuyerOrderReferencedDocument");
+	}
+
+	/**
+	 * @return the SellerOrderReferencedDocument IssuerAssigned ID
+	 */
+	public String getSellerOrderReferencedDocumentIssuerAssignedID() {
+		return extractIssuerAssignedID("SellerOrderReferencedDocument");
+	}
+
+  /**
+	 * @return the IssuerAssigned ID
+	 */
+	public String getContractOrderReferencedDocumentIssuerAssignedID() {
+		return extractIssuerAssignedID("ContractReferencedDocument");
+	}
+
+	private String extractIssuerAssignedID(String propertyName) {
 		try {
 			if (getVersion() == 1) {
 				return extractString("//BuyerOrderReferencedDocument//ID");
 			} else {
 				return extractString("//BuyerOrderReferencedDocument//IssuerAssignedID");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -302,7 +328,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//ExchangedDocument//IssueDateTime//DateTimeString");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -318,7 +344,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//SpecifiedTradeSettlementHeaderMonetarySummation//TaxBasisTotalAmount");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -334,7 +360,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//SpecifiedTradeSettlementHeaderMonetarySummation//TaxTotalAmount");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -350,7 +376,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//SpecifiedTradeSettlementHeaderMonetarySummation//RoundingAmount");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -366,7 +392,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//SpecifiedTradeSettlementHeaderMonetarySummation//TotalPrepaidAmount");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -404,7 +430,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//ExchangedDocument//IncludedNote");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -429,7 +455,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//SpecifiedTradeSettlementHeaderMonetarySummation//LineTotalAmount");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -452,7 +478,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//ActualDeliverySupplyChainEvent//OccurrenceDateTime//DateTimeString");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -468,7 +494,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//ExchangedDocument//ID");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -486,7 +512,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//ExchangedDocument/TypeCode");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -503,7 +529,7 @@ public class ZUGFeRDImporter {
 			} else {
 				return extractString("//ApplicableHeaderTradeAgreement/BuyerReference");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return "";
 		}
@@ -628,7 +654,7 @@ public class ZUGFeRDImporter {
 		}
 
 
-		byte[] bomlessData;
+		final byte[] bomlessData;
 
 		if ((rawXML[0] == (byte) 0xEF)
 				&& (rawXML[1] == (byte) 0xBB)
@@ -664,7 +690,7 @@ public class ZUGFeRDImporter {
 
 		// SpecifiedExchangedDocumentContext is in the schema, so a relatively good
 		// indication if zugferd is present - better than just invoice
-		String meta = getMeta();
+		final String meta = getMeta();
 		return (meta != null) && (meta.length() > 0) && ((meta.contains("SpecifiedExchangedDocumentContext")
 				/* ZF1 */ || meta.contains("ExchangedDocumentContext") /* ZF2 */));
 	}
@@ -673,7 +699,7 @@ public class ZUGFeRDImporter {
 	static String convertStreamToString(java.io.InputStream is) {
 		// source https://stackoverflow.com/questions/309424/how-do-i-read-convert-an-inputstream-into-a-string-in-java referring to
 		// https://community.oracle.com/blogs/pat/2004/10/23/stupid-scanner-tricks
-		Scanner s = new Scanner(is, "UTF-8").useDelimiter("\\A");
+		final Scanner s = new Scanner(is, "UTF-8").useDelimiter("\\A");
 		return s.hasNext() ? s.next() : "";
 	}
 
@@ -691,7 +717,7 @@ public class ZUGFeRDImporter {
 			} else {
 				nl = getNodeListByPath("//CrossIndustryInvoice//SupplyChainTradeTransaction//ApplicableHeaderTradeAgreement//BuyerTradeParty//PostalTradeAddress");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return null;
 		}
@@ -706,7 +732,7 @@ public class ZUGFeRDImporter {
 	public PostalTradeAddress getSellerTradePartyAddress() {
 
 		NodeList nl = null;
-		PostalTradeAddress address = new PostalTradeAddress();
+		final PostalTradeAddress address = new PostalTradeAddress();
 
 		try {
 			if (getVersion() == 1) {
@@ -714,7 +740,7 @@ public class ZUGFeRDImporter {
 			} else {
 				nl = getNodeListByPath("//CrossIndustryInvoice//SupplyChainTradeTransaction//ApplicableHeaderTradeAgreement//SellerTradeParty//PostalTradeAddress");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return null;
 		}
@@ -723,15 +749,15 @@ public class ZUGFeRDImporter {
 	}
 
 	private PostalTradeAddress getAddressFromNodeList(NodeList nl) {
-		PostalTradeAddress address = new PostalTradeAddress();
+		final PostalTradeAddress address = new PostalTradeAddress();
 
 		if (nl != null) {
 			for (int i = 0; i < nl.getLength(); i++) {
 				Node n = nl.item(i);
-				NodeList nodes = n.getChildNodes();
+				final NodeList nodes = n.getChildNodes();
 				for (int j = 0; j < nodes.getLength(); j++) {
 					n = nodes.item(j);
-					short nodeType = n.getNodeType();
+					final short nodeType = n.getNodeType();
 					if (nodeType==Node.ELEMENT_NODE){
 						switch (n.getNodeName()) {
 							case "ram:PostcodeCode":
@@ -789,16 +815,16 @@ public class ZUGFeRDImporter {
 	 * @return a List of LineItem instances
 	 */
 	public List<Item> getLineItemList() {
-		List<Node> nodeList = getLineItemNodes();
+		final List<Node> nodeList = getLineItemNodes();
-		List<Item> lineItemList = new ArrayList<>();
+		final List<Item> lineItemList = new ArrayList<>();
 
-		for (Node n: nodeList) {
+		for (final Node n: nodeList) {
-			Item lineItem = new Item(null, null, null);
+			final Item lineItem = new Item(null, null, null);
 			lineItem.setProduct(new Product(null,null,null,null));
 
-			NodeList nl = n.getChildNodes();
+			final NodeList nl = n.getChildNodes();
 			for (int i = 0; i < nl.getLength(); i++) {
-				Node nn = nl.item(i);
+				final Node nn = nl.item(i);
 				Node node = null;
 				switch (nn.getNodeName()) {
 					case "ram:SpecifiedLineTradeAgreement":
@@ -806,12 +832,12 @@ public class ZUGFeRDImporter {
 
 						node = getNodeByName(nn.getChildNodes(), "ram:NetPriceProductTradePrice");
 						if (node != null) {
-						    NodeList tradeAgreementChildren = node.getChildNodes();
+						    final NodeList tradeAgreementChildren = node.getChildNodes();
 						    node = getNodeByName(tradeAgreementChildren, "ram:ChargeAmount");
 						    lineItem.setPrice(tryBigDecimal(getNodeValue(node)));
 						    node = getNodeByName(tradeAgreementChildren, "ram:BasisQuantity");
 							if(node != null && node.getAttributes()!=null) {
-								Node unitCodeAttribute = node.getAttributes().getNamedItem("unitCode");
+								final Node unitCodeAttribute = node.getAttributes().getNamedItem("unitCode");
 								if(unitCodeAttribute != null) {
 									lineItem.getProduct().setUnit(unitCodeAttribute.getNodeValue());
 								}
@@ -905,7 +931,7 @@ public class ZUGFeRDImporter {
 	 * @return a List of Node instances
 	 */
 	public List<Node> getLineItemNodes() {
-		List<Node> lineItemNodes = new ArrayList<>();
+		final List<Node> lineItemNodes = new ArrayList<>();
 		NodeList nl = null;
 		try {
 			if (getVersion() == 1) {
@@ -913,12 +939,12 @@ public class ZUGFeRDImporter {
 			} else {
 				nl = getNodeListByPath("//CrossIndustryInvoice//SupplyChainTradeTransaction//IncludedSupplyChainTradeLineItem");
 			}
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 		}
 
 		for (int i = 0; i < nl.getLength(); i++) {
-			Node n = nl.item(i);
+			final Node n = nl.item(i);
 			lineItemNodes.add(n);
 		}
 		return lineItemNodes;
@@ -935,7 +961,7 @@ public class ZUGFeRDImporter {
 			if (nl.item(i).getNodeName() == name) {
 				return nl.item(i);
 			} else if (nl.item(i).getChildNodes().getLength() > 0) {
-				Node node = getNodeByName(nl.item(i).getChildNodes(), name);
+				final Node node = getNodeByName(nl.item(i).getChildNodes(), name);
 				if (node != null) {
 					return node;
 				}
@@ -951,14 +977,14 @@ public class ZUGFeRDImporter {
 	 */
 	public NodeList getNodeListByPath(String path) {
 
-		XPathFactory xpathFact = XPathFactory.newInstance();
+		final XPathFactory xpathFact = XPathFactory.newInstance();
-		XPath xPath = xpathFact.newXPath();
+		final XPath xPath = xpathFact.newXPath();
-		String s = path;
+		final String s = path;
 
 		try {
-			XPathExpression xpr = xPath.compile(s);
+			final XPathExpression xpr = xPath.compile(s);
 			return (NodeList) xpr.evaluate(getDocument(), XPathConstants.NODESET);
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			e.printStackTrace();
 			return null;
 		}
@@ -986,10 +1012,10 @@ public class ZUGFeRDImporter {
 	private BigDecimal tryBigDecimal(String nodeValue) {
 		try {
 			return new BigDecimal(nodeValue);
-		} catch (Exception e) {
+		} catch (final Exception e) {
 			try {
 				return new BigDecimal(Float.valueOf(nodeValue));
-			} catch (Exception ex) {
+			} catch (final Exception ex) {
 				return new BigDecimal("0.00");
 			}
 		}