--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main/java/org/mpi/openmind/repository/utils/CsvEntityListWriter.java	Thu Nov 03 20:12:11 2016 +0100
@@ -0,0 +1,75 @@
+/**
+ * 
+ */
+package org.mpi.openmind.repository.utils;
+
+import java.io.IOException;
+import java.util.HashSet;
+import java.util.List;
+import java.util.Set;
+
+import org.apache.commons.csv.CSVFormat;
+import org.apache.commons.csv.CSVPrinter;
+import org.apache.commons.csv.QuoteMode;
+import org.apache.commons.lang.ArrayUtils;
+import org.mpi.openmind.repository.bo.Attribute;
+import org.mpi.openmind.repository.bo.Entity;
+
+/**
+ * Class that creates a CSV file from a List of Entities.
+ * 
+ * Creates columns for all Attributes.
+ * 
+ * @author casties
+ *
+ */
+public class CsvEntityListWriter {
+
+    public static void writeEntities(List<Entity> entities, Appendable output) throws IOException {
+        Set<String> attNameSet = new HashSet<String>();
+        /*
+         * create a list of all attribute names
+         */
+        for (Entity entity : entities) {
+            for (Attribute att : entity.getAttributes()) {
+                attNameSet.add(att.getName());
+            }
+        }
+        String[] attNames = attNameSet.toArray(new String[attNameSet.size()]);
+        String[] entProps = new String[] {"id", "object_class", "own_value"};
+        String[] headers = (String[]) ArrayUtils.addAll(entProps, attNames);
+        // create CSV format with header
+        CSVFormat format = CSVFormat.DEFAULT.withHeader(headers).withQuoteMode(QuoteMode.NON_NUMERIC);
+        // create CSVPrinter
+        CSVPrinter printer = new CSVPrinter(output, format);
+        
+        /*
+         * print all Entities
+         */
+        for (Entity entity : entities) {
+            for (String field : headers) {
+                if (field.equals("id")) {
+                    printer.print(entity.getId());
+                    
+                } else if (field.equals("object_class")) {
+                    printer.print(entity.getObjectClass());
+                    
+                } else if (field.equals("own_value")) {
+                    printer.print(entity.getOwnValue());
+                    
+                } else {
+                    // print attribute
+                    Attribute att = entity.getAttributeByName(field);
+                    if (att != null) {
+                        printer.print(att.getOwnValue());
+                    } else {
+                        printer.print(null);
+                    }
+                }
+            }
+            printer.println();
+        }
+        printer.flush();
+        printer.close();
+    }
+}