attempt for new tests(which compile but do not yet even fail)

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

@@ -0,0 +1,12 @@
+package org.mustangproject;
+
+import org.mustangproject.ZUGFeRD.IZUGFeRDAllowanceCharge;
+
+import java.math.BigDecimal;
+
+public class Allowance extends Charge {
+
+	public Allowance(BigDecimal totalAmount, BigDecimal taxPercent, String categoryCode, String reason) {
+		super(totalAmount, taxPercent, categoryCode, reason);
+	}
+}

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

@@ -0,0 +1,60 @@
+package org.mustangproject;
+
+import org.mustangproject.ZUGFeRD.IZUGFeRDAllowanceCharge;
+import org.mustangproject.ZUGFeRD.IZUGFeRDExportableContact;
+
+import java.math.BigDecimal;
+
+public class Charge implements IZUGFeRDAllowanceCharge {
+	protected String reason;
+	protected BigDecimal totalAmount;
+	protected BigDecimal taxPercent;
+	protected String categoryCode;
+
+	public Charge(BigDecimal totalAmount, BigDecimal taxPercent, String categoryCode, String reason) {
+		this.totalAmount=totalAmount;
+		this.taxPercent=taxPercent;
+		this.categoryCode=categoryCode;
+		this.reason=reason;
+	}
+
+	@Override
+	public String getReason() {
+		return reason;
+	}
+
+	public Charge setReason(String reason) {
+		this.reason = reason;
+		return this;
+	}
+
+	@Override
+	public BigDecimal getTotalAmount() {
+		return totalAmount;
+	}
+
+	public Charge setTotalAmount(BigDecimal totalAmount) {
+		this.totalAmount = totalAmount;
+		return this;
+	}
+
+	@Override
+	public BigDecimal getTaxPercent() {
+		return taxPercent;
+	}
+
+	public Charge setTaxPercent(BigDecimal taxPercent) {
+		this.taxPercent = taxPercent;
+		return this;
+	}
+
+	@Override
+	public String getCategoryCode() {
+		return categoryCode;
+	}
+
+	public Charge setCategoryCode(String categoryCode) {
+		this.categoryCode = categoryCode;
+		return this;
+	}
+}

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

@@ -34,7 +34,8 @@ public class Invoice implements IExportableTransaction {
 	protected IZUGFeRDExportableContact ownContact = null, recipient = null, deliveryAddress = null;
 	protected ArrayList<IZUGFeRDExportableItem> ZFItems = null;
 
-	protected IZUGFeRDAllowanceCharge[] ZFAllowances = null, ZFCharges = null, ZFLogisticsServiceCharges = null;
+	protected ArrayList<IZUGFeRDAllowanceCharge> Allowances = new ArrayList<IZUGFeRDAllowanceCharge>(),
+			Charges = new ArrayList<IZUGFeRDAllowanceCharge>(), LogisticsServiceCharges = new ArrayList<IZUGFeRDAllowanceCharge>();
 	protected IZUGFeRDTradeSettlement[] getTradeSettlement = null;
 	protected IZUGFeRDPaymentTerms paymentTerms = null;
 
@@ -334,33 +335,30 @@ public class Invoice implements IExportableTransaction {
 
 	@Override
 	public IZUGFeRDAllowanceCharge[] getZFAllowances() {
-		return ZFAllowances;
+		if (Allowances.isEmpty()) {
+			return null;
+		} else
+		return Allowances.toArray(new IZUGFeRDAllowanceCharge[0]);
 	}
 
-	public Invoice setZFAllowances(IZUGFeRDAllowanceCharge[] ZFAllowances) {
-		this.ZFAllowances = ZFAllowances;
-		return this;
-	}
 
 	@Override
 	public IZUGFeRDAllowanceCharge[] getZFCharges() {
-		return ZFCharges;
+		if (Charges.isEmpty()) {
+			return null;
+		} else
+			return Charges.toArray(new IZUGFeRDAllowanceCharge[0]);
 	}
 
-	public Invoice setZFCharges(IZUGFeRDAllowanceCharge[] ZFCharges) {
-		this.ZFCharges = ZFCharges;
-		return this;
-	}
 
 	@Override
 	public IZUGFeRDAllowanceCharge[] getZFLogisticsServiceCharges() {
-		return ZFLogisticsServiceCharges;
+		if (LogisticsServiceCharges.isEmpty()) {
+			return null;
+		} else
+			return LogisticsServiceCharges.toArray(new IZUGFeRDAllowanceCharge[0]);
 	}
 
-	public Invoice setZFLogisticsServiceCharges(IZUGFeRDAllowanceCharge[] ZFLogisticsServiceCharges) {
-		this.ZFLogisticsServiceCharges = ZFLogisticsServiceCharges;
-		return this;
-	}
 
 	public IZUGFeRDTradeSettlement[] getGetTradeSettlement() {
 		return getTradeSettlement;
@@ -413,4 +411,12 @@ public class Invoice implements IExportableTransaction {
 		//		this.country = country;
 	}
 
+	public Invoice addCharge(IZUGFeRDAllowanceCharge izac) {
+		Charges.add(izac);
+		return this;
+	}
+	public Invoice addAllowance(IZUGFeRDAllowanceCharge izac) {
+		Allowances.add(izac);
+		return this;
+	}
 }

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

@@ -4,11 +4,14 @@ import org.mustangproject.ZUGFeRD.IZUGFeRDAllowanceCharge;
 import org.mustangproject.ZUGFeRD.IZUGFeRDExportableItem;
 
 import java.math.BigDecimal;
+import java.util.ArrayList;
 
 public class Item implements IZUGFeRDExportableItem {
 	protected BigDecimal price, quantity, tax, grossPrice, lineTotalAmount;
 	protected String id;
 	protected Product product;
+	protected ArrayList<IZUGFeRDAllowanceCharge> Allowances = new ArrayList<IZUGFeRDAllowanceCharge>(),
+			Charges = new ArrayList<IZUGFeRDAllowanceCharge>();
 
 	public Item(Product product, BigDecimal price, BigDecimal quantity) {
 		this.price = price;
@@ -81,16 +84,32 @@ public class Item implements IZUGFeRDExportableItem {
 
 	@Override
 	public IZUGFeRDAllowanceCharge[] getItemAllowances() {
-		return null;
+		if (Allowances.isEmpty()) {
+			return null;
+		} else
+			return Allowances.toArray(new IZUGFeRDAllowanceCharge[0]);
 	}
 
 	@Override
 	public IZUGFeRDAllowanceCharge[] getItemCharges() {
-		return null;
+		if (Charges.isEmpty()) {
+			return null;
+		} else
+			return Charges.toArray(new IZUGFeRDAllowanceCharge[0]);
 	}
 
 	public Item setProduct(Product product) {
 		this.product = product;
 		return this;
 	}
+
+
+	public Item addCharge(IZUGFeRDAllowanceCharge izac) {
+		Charges.add(izac);
+		return this;
+	}
+	public Item addAllowance(IZUGFeRDAllowanceCharge izac) {
+		Allowances.add(izac);
+		return this;
+	}
 }

library/src/main/java/org/mustangproject/ZUGFeRD/ZUGFeRDExporterFromA3.java

@@ -208,6 +208,9 @@ public class ZUGFeRDExporterFromA3 extends XRExporter implements IZUGFeRDExporte
 		ensurePDFisUpgraded = false;
 	}
 
+	public void attachFile(String filename, byte[] data, String mimetype, String relation) {
+		//throw new RuntimeException("Not implemented");
+	}
 
 	/***
 	 * Perform the final export to a now ZUGFeRD-enriched PDF file