diff --git a/src/main/java/de/uniluebeck/mi/projmi6/hapi/HL7Receiver.java b/src/main/java/de/uniluebeck/mi/projmi6/hapi/HL7Receiver.java
index 9b4cf9d..5280b09 100644
--- a/src/main/java/de/uniluebeck/mi/projmi6/hapi/HL7Receiver.java
+++ b/src/main/java/de/uniluebeck/mi/projmi6/hapi/HL7Receiver.java
@@ -25,7 +25,8 @@ import java.util.List;
 import java.util.Map;
 
 /**
- * Created by nils on 20.11.2015.
+ * Manages all HL7 receiving tasks
+ * @param <T>
  */
 public class HL7Receiver<T extends AbstractMessage> implements ReceivingApplication {
     private final Class<T> type;
@@ -60,6 +61,12 @@ public class HL7Receiver<T extends AbstractMessage> implements ReceivingApplicat
         return type.isInstance(message);
     }
 
+    /**
+     * generates an ACK of received message, throws Exception otherwise
+     * @param message to generate ACK
+     * @return ACK of message
+     * @throws HL7Exception
+     */
     private Message generateACK(Message message) throws HL7Exception {
         try {
             return message.generateACK();
@@ -68,6 +75,13 @@ public class HL7Receiver<T extends AbstractMessage> implements ReceivingApplicat
         }
     }
 
+    /**
+     * generates an ACK with error code and log
+     * @param message to generate ACK
+     * @param s error string
+     * @return ACK with error code
+     * @throws HL7Exception
+     */
     private Message generateACKWithAR(Message message, String s) throws HL7Exception {
         try {
             Message returnMessage = message.generateACK(AcknowledgmentCode.AR, new HL7Exception(s, ErrorCode.UNKNOWN_KEY_IDENTIFIER));
@@ -83,27 +97,35 @@ public class HL7Receiver<T extends AbstractMessage> implements ReceivingApplicat
         }
     }
 
+    /**
+     * encodes incoming message and save changes in database
+     * @param message received
+     * @param metadata //TODO
+     * @return ACK of message
+     * @throws HL7Exception
+     */
     private Message processBAR_P05(Message message, Map<String, Object> metadata) throws HL7Exception {
         BAR_P05 bar_p05 = (BAR_P05) message;
 
         MSH msh = bar_p05.getMSH();
         PID pid = bar_p05.getPID();
-
+        //get patient of the message
         int patid = Integer.parseInt(pid.getPatientID().encode());
         Patient patient = mainctrl.getStammdaten().getPatienten().stream().filter(p -> p.getPatID() == patid).findFirst().orElse(null);
 
+        //error by unknown patient
         if (patient == null) {
             HL7Utils.logInHL7MessageToDatabase(message, msh, metadata);
             updateUI(new HL7Message(null, -1, LocalDateTime.now(), "Patient nicht gefunden.", true));
             return generateACKWithAR(message, "Patient nicht gefunden.");
-        } // TODO: Patienten und Fall neu anlegen??? Nicht verlangt!
+        }
 
         List<BAR_P05_VISIT> visits = bar_p05.getVISITAll();
 
         List<Integer> updatedFallIDs = new ArrayList<>();
 
-        // Ab hier wird es dirty.
         for (BAR_P05_VISIT visit : visits) {
+            //get current fall
             PV1 pv1 = visit.getPV1();
             int fallid = Integer.parseInt(pv1.getVisitNumber().getIDNumber().encode());
 
@@ -113,6 +135,7 @@ public class HL7Receiver<T extends AbstractMessage> implements ReceivingApplicat
             } catch (SQLException e) {
                 e.printStackTrace();
             }
+            //log error by unknown fall
             if (fallids.isEmpty() || !fallids.contains(fallid)) {
                 HL7Utils.logInHL7MessageToDatabase(message, msh, metadata);
                 updateUI(new HL7Message(patient, -1, LocalDateTime.now(), "Fall nicht gefunden.?", true));
@@ -129,8 +152,9 @@ public class HL7Receiver<T extends AbstractMessage> implements ReceivingApplicat
             // Station(PV1-3-1), Fachabteilung(PV1-3-4), Aufnahmedatum(PV1-44), Entlassungsdatum(PV1-45), Fallnummer(PV1-19)
             String stat = pv1.getAssignedPatientLocation().getPointOfCare().encode();
             Station station = mainctrl.getStammdaten().getStationen().stream().filter(s -> s.getStation().equals(stat)).findFirst().orElse(null);
-            // TODO: Stationen mit falschen Abteilungen werden einfach umgeschrieben^^
+            //TODO ATTENTION wrong abteilungen may write down here
 
+            //error message when station not exists
             if (station == null) {
                 HL7Utils.logInHL7MessageToDatabase(message, msh, metadata);
                 updateUI(new HL7Message(patient, -1, LocalDateTime.now(), "Station nicht gefunden.", true));
@@ -149,9 +173,11 @@ public class HL7Receiver<T extends AbstractMessage> implements ReceivingApplicat
             }
             hist.setFallID(fallid);
 
+            //diagnosis
             List<DG1> dg1s = visit.getDG1All();
             for (DG1 dg1 : dg1s) {
                 Diagnose diagnose = new Diagnose();
+                //default value by OPS ersteller and bearbeiter
                 diagnose.setErsteller(99999);
                 diagnose.setBearbeiter(99999);
                 diagnose.setFall(fall);