Add new getter and classes

IExportableTransaction#getNotesWithSubjectCode
IncludedNote
SubjectCode

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

@@ -0,0 +1,42 @@
+package org.mustangproject;
+
+/**
+ * A grouping of business terms to indicate accounting-relevant free texts including a qualification of these.
+ */
+public class IncludedNote {
+  private final String content;
+  private final SubjectCode subjectCode;
+
+  private IncludedNote(String content, SubjectCode subjectCode) {
+    this.content = content;
+    this.subjectCode = subjectCode;
+  }
+
+  public static IncludedNote generalNote(String content) {
+    return new IncludedNote(content, SubjectCode.AAI);
+  }
+  public static IncludedNote regulatoryNote(String content) {
+    return new IncludedNote(content, SubjectCode.REG);
+  }
+  public static IncludedNote legalNote(String content) {
+    return new IncludedNote(content, SubjectCode.ABL);
+  }
+  public static IncludedNote customsNote(String content) {
+    return new IncludedNote(content, SubjectCode.CUS);
+  }
+  public static IncludedNote sellerNote(String content) {
+    return new IncludedNote(content, SubjectCode.SUR);
+  }
+  public static IncludedNote taxNote(String content) {
+    return new IncludedNote(content, SubjectCode.TXD);
+  }
+
+  public String getContent() {
+    return content;
+  }
+
+  public SubjectCode getSubjectCode() {
+    return subjectCode;
+  }
+  
+}

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

@@ -0,0 +1,31 @@
+package org.mustangproject;
+
+/**
+ * the qualification of the free text on the invoice from BT-22
+ */
+public enum SubjectCode {
+  /**
+   * general information
+   */
+  AAI,
+  /**
+   * seller notes
+   */
+  SUR,
+  /**
+   * regulatory information
+   */
+  REG,
+  /**
+   * legal information
+   */
+  ABL,
+  /**
+   * tax information
+   */
+  TXD,
+  /**
+   * Customs information
+   */
+  CUS
+}

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

@@ -29,8 +29,10 @@ package org.mustangproject.ZUGFeRD;
 
 import java.math.BigDecimal;
 import java.util.Date;
+import java.util.List;
 
 import org.mustangproject.FileAttachment;
+import org.mustangproject.IncludedNote;
 import org.mustangproject.ZUGFeRD.model.DocumentCodeTypeConstants;
 
 /***
@@ -80,10 +82,13 @@ public interface IExportableTransaction {
 	/**
 	 * this should be the full sender institution name, details, manager and tax
 	 * registration. It is one of the few functions which may return null. e.g.
-	 * <p>
+	 * <p/>
 	 * Lieferant GmbH Lieferantenstraße 20 80333 München Deutschland
 	 * Geschäftsführer: Hans Muster Handelsregisternummer: H A 123
+   * <p/>
 	 *
+   * It is written as an includedNode with subjectCode {@link org.mustangproject.SubjectCode#REG}. See also 
+   * {@link #getNotesWithSubjectCode()}
 	 * @return null or full sender institution name, details, manager and tax
 	 *         registration
 	 */
@@ -489,6 +494,13 @@ public interface IExportableTransaction {
 		return null;
 	}
 
+  /**
+   * A grouping of business terms to indicate accounting-relevant free texts including a qualification of these. <p/>
+   * The information are written to the same xml nodes like {@link #getNotes()} but with explicit subjectCode.
+   */
+  default List<IncludedNote> getNotesWithSubjectCode(){
+    return null;
+  }
 	default String getSpecifiedProcuringProjectName() {
 		return null;
 	}