diff --git a/java/org/slub/rosetta/dps/repository/plugin/SLUBTechnicalMetadataExtractorMediaConchPlugin.java b/java/org/slub/rosetta/dps/repository/plugin/SLUBTechnicalMetadataExtractorMediaConchPlugin.java
index 99740b05a1608b9d9113033bd97a99486d0c8edb..3c96db0f8cb9905d0022cbca0b32e8d9a556ee01 100644
--- a/java/org/slub/rosetta/dps/repository/plugin/SLUBTechnicalMetadataExtractorMediaConchPlugin.java
+++ b/java/org/slub/rosetta/dps/repository/plugin/SLUBTechnicalMetadataExtractorMediaConchPlugin.java
@@ -69,10 +69,10 @@ public class SLUBTechnicalMetadataExtractorMediaConchPlugin implements MDExtract
     private final static String MEDIAINFO_XSD = "/transformer.xsl";
 
     private List<String> extractionErrors = new ArrayList<>();
-    private List<String> validationLog = new ArrayList<>();
+    private final List<String> validationLog = new ArrayList<>();
     private boolean isvalid = false;
     private boolean iswellformed = false;
-    private Map<String,String> attributes = new HashMap<>();
+    private final Map<String,String> attributes = new HashMap<>();
 
     //static final ExLogger log = ExLogger.getExLogger(SLUBTechnicalMetadataExtractorMediaConchPlugin.class, ExLogger.VALIDATIONSTACK);
     /** constructor */
@@ -150,7 +150,7 @@ public class SLUBTechnicalMetadataExtractorMediaConchPlugin implements MDExtract
             //mediainfo_output.append(line);
             line = reader.readLine();
         }
-
+        reader.close();
         File temp_media_outputfile = File.createTempFile("mediainfo_outp", ".xml");
         temp_media_outputfile.deleteOnExit();
         File temp_media_transformed_outputfile = File.createTempFile("mediainfo_transf_", ".xml");
@@ -235,6 +235,7 @@ public class SLUBTechnicalMetadataExtractorMediaConchPlugin implements MDExtract
             validationLog.add(line);
             line = reader.readLine();
         }
+        reader.close();
         extractionErrors = validationLog;
     }
 
@@ -272,18 +273,19 @@ public class SLUBTechnicalMetadataExtractorMediaConchPlugin implements MDExtract
                 String line = null;
                 try {
                     line = reader.readLine();
+                    while (line != null) {
+                        System.out.println(line);
+                        response.append(line);
+                        try {
+                            line = reader.readLine();
+                        } catch (IOException e) {
+                            e.printStackTrace();
+                        }
+                    }
+                    reader.close();
                 } catch (IOException e) {
                     e.printStackTrace();
                 }
-                while (line != null) {
-                    System.out.println(line);
-                    response.append(line);
-                    try {
-                        line = reader.readLine();
-                    } catch (IOException e) {
-                        e.printStackTrace();
-                    }
-                }
             }
         }
         return response.toString().trim();
@@ -491,8 +493,9 @@ public class SLUBTechnicalMetadataExtractorMediaConchPlugin implements MDExtract
         System.out.println( plugin.getProfile());
         System.out.println("----------------------------------");
         System.out.println("getAttributeByName (summarized):");
-        for (Map.Entry m: plugin.attributes.entrySet()) {
-            System.out.println( m.getKey() + " -> " + m.getValue());
+        for (Map.Entry<String, String> m : plugin.attributes.entrySet()) {
+            String s = m.getKey() + " -> " + m.getValue();
+            System.out.println(s);
         }
     }
 }