diff --git a/CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/zip/CityGmlZipEntryFile.java b/CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/zip/CityGmlZipEntryFile.java
index e8c8aaca2b74c3ad999a6327d082b46b787513b8..3bf82fe00a2490d9eef2eb715ef6edc5a4a14786 100644
--- a/CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/zip/CityGmlZipEntryFile.java
+++ b/CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/zip/CityGmlZipEntryFile.java
@@ -42,7 +42,7 @@ public class CityGmlZipEntryFile implements AutoCloseable {
      */
     public InputStream getInputStream() throws IOException {
         if (closed){
-            throw new IOException("Stream closed");
+            throw new IOException("CityGmlZipEntryFile closed");
         }
         return zip.getInputStream(zipEntry);
     }
@@ -54,7 +54,7 @@ public class CityGmlZipEntryFile implements AutoCloseable {
      */
     public long getFileSize() throws IOException {
         if (closed){
-            throw new IOException("Stream closed");
+            throw new IOException("CityGmlZipEntryFile closed");
         }
         if (cgmlZipEntry.getFileSize() == -1L) {
             if (zipEntry.getSize() == -1) {
diff --git a/CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/zip/MalformedZipFileException.java b/CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/zip/MalformedZipFileException.java
index c02f6c0206bdb68916b01d627098fccfc5e3e882..759fbe6bffca2ee965fbbb0b84a35b6202398084 100644
--- a/CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/zip/MalformedZipFileException.java
+++ b/CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/zip/MalformedZipFileException.java
@@ -2,6 +2,9 @@ package de.hft.stuttgart.citydoctor2.zip;
 
 import java.util.zip.ZipException;
 
+/**
+ * Signals that a ZIP-file is corrupted and couldn't be parsed.
+ */
 public class MalformedZipFileException extends ZipException {
 
     public MalformedZipFileException() {
diff --git a/CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/CheckDialog.java b/CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/CheckDialog.java
index 576b7820e4a653bb8fb104beb389d987b6eaaafb..23ae6271bcbd5cd62f8fde072e25fd3ad19ac852 100644
--- a/CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/CheckDialog.java
+++ b/CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/CheckDialog.java
@@ -316,6 +316,11 @@ public class CheckDialog {
 		showZipArchiveOptions(false);
 	}
 
+	/**
+	 * Shows the option panel for ZIP-Archive checking and enables the ZIP-Archive checking mode for this dialog.
+	 *
+	 * @param enabled
+	 */
 	public void showZipArchiveOptions(boolean enabled) {
 		zipArchiveOptionsVBox.setDisable(!enabled);
 		zipArchiveOptionsVBox.setVisible(enabled);
diff --git a/CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/ZipEntryManager.java b/CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/ZipEntryManager.java
index fd8abeeaa9c3906d2a5c08226afdd2ea26ea5095..2429a5ff003debeda1780d60e979bd06fe7239ec 100644
--- a/CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/ZipEntryManager.java
+++ b/CityDoctorParent/Extensions/CityDoctorGUI/src/main/java/de/hft/stuttgart/citydoctor2/gui/ZipEntryManager.java
@@ -34,6 +34,9 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.util.function.Predicate;
 
+/**
+ * This class implements a GUI for managing a loaded {@link CityGmlZipArchive} in CityDoctor.
+ */
 public class ZipEntryManager {
 
     private static final Logger logger = LogManager.getLogger(ZipEntryManager.class);
@@ -217,10 +220,6 @@ public class ZipEntryManager {
                 }
                 CityGmlZipEntry entry = entryList.getSelectionModel().getSelectedItem().getEntry();
                 if (entry.getErrorType() != null) {
-                    /**
-                     * Button should be disabled when an erroneous entry gets selected.
-                     * Silently fail in case an erroneous entry is somehow selected on Action.
-                     */
                     logger.debug("IllegalState: loadBtn was pressed while an erroneous entry was selected");
                     populateZipEntryList(selectedIndex);
                     return;