[DS-1140] New POI-based MS Word extractor and some comment cleanup

dspace-api/src/main/java/org/dspace/app/mediafilter/FormatFilter.java

@@ -44,18 +44,20 @@ public interface FormatFilter
     public String getFormatString();
 
     /**
-     * @return string to describe the newly-generated Bitstream's - how it was
+     * @return string to describe the newly-generated Bitstream - how it was
      *         produced is a good idea
      */
     public String getDescription();
 
     /**
+     * Read the source stream and produce the filtered content.
+     *
      * @param item Item
      * @param source
      *            input stream
      * @param verbose verbosity flag
      * 
-     * @return result of filter's transformation, written out to a bitstream
+     * @return result of filter's transformation as a byte stream.
      * @throws Exception if error
      */
     public InputStream getDestinationStream(Item item, InputStream source, boolean verbose)

dspace-api/src/main/java/org/dspace/app/mediafilter/PoiWordFilter.java

@@ -0,0 +1,89 @@
+/**
+ * The contents of this file are subject to the license and copyright
+ * detailed in the LICENSE and NOTICE files at the root of the source
+ * tree and available online at
+ *
+ * http://www.dspace.org/license/
+ */
+package org.dspace.app.mediafilter;
+
+import java.io.ByteArrayInputStream;
+import java.io.InputStream;
+import java.io.IOException;
+
+import org.apache.poi.POITextExtractor;
+import org.apache.poi.extractor.ExtractorFactory;
+import org.apache.poi.hwpf.extractor.WordExtractor;
+import org.apache.poi.xwpf.extractor.XWPFWordExtractor;
+import org.dspace.content.Item;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * Extract flat text from Microsoft Word documents (.doc, .docx).
+ */
+public class PoiWordFilter
+        extends MediaFilter
+{
+    private static final Logger LOG = LoggerFactory.getLogger(PoiWordFilter.class);
+
+    @Override
+    public String getFilteredName(String oldFilename)
+    {
+        return oldFilename + ".txt";
+    }
+
+    @Override
+    public String getBundleName()
+    {
+        return "TEXT";
+    }
+
+    @Override
+    public String getFormatString()
+    {
+        return "Text";
+    }
+
+    @Override
+    public String getDescription()
+    {
+        return "Extracted text";
+    }
+
+    @Override
+    public InputStream getDestinationStream(Item currentItem, InputStream source, boolean verbose)
+            throws Exception
+    {
+        try  
+        {
+            // get input stream from bitstream, pass to filter, get string back
+            String text;
+            POITextExtractor extractor = ExtractorFactory.createExtractor(source);
+            if (extractor instanceof XWPFWordExtractor)
+                text = ((XWPFWordExtractor) extractor).getText();
+            else if (extractor instanceof WordExtractor)
+                text = ((WordExtractor) extractor).getText();
+            else
+                throw new IllegalArgumentException(
+                        "Bitstream is neither .doc nor .docx format.  Extractor returned a "
+                                + extractor.getClass().getCanonicalName());
+
+            // if verbose flag is set, print out extracted text to STDOUT
+            if (verbose)
+            {
+                System.out.println(text);
+            }
+
+            // return the extracted text as a stream.
+            return new ByteArrayInputStream(text.getBytes());
+        } 
+        catch (IOException ioe)
+        {
+            System.out.println("Invalid File Format");
+            LOG.error("Error detected - Microsoft Word file format not recognized: "
+                    + ioe.getMessage(), ioe);
+            throw ioe;
+        }
+    }
+}