Move the citation generation in a single method again

dspace-api/src/main/java/org/dspace/curate/CitationPage.java

@@ -154,7 +154,7 @@ public class CitationPage extends AbstractCurationTask {
                     try {
                         //Create the cited document
                         InputStream citedInputStream =
-                            citationDocument.getCitedDocument(Curator.curationContext(), bitstream);
+                            citationDocument.makeCitedDocument(Curator.curationContext(), bitstream).getLeft();
                         //Add the cited document to the approiate bundle
                         this.addCitedPageToItem(citedInputStream, bundle, pBundle,
                                                 dBundle, displayMap, item, bitstream);

dspace-api/src/main/java/org/dspace/disseminate/CitationDocumentServiceImpl.java

@@ -21,6 +21,7 @@ import java.util.List;
 import java.util.Set;
 
 import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.tuple.Pair;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.apache.pdfbox.pdmodel.PDDocument;
@@ -296,33 +297,30 @@ public class CitationDocumentServiceImpl implements CitationDocumentService, Ini
     }
 
     @Override
-    public InputStream getCitedDocument(Context context, Bitstream bitstream)
+    public Pair<InputStream, Long> makeCitedDocument(Context context, Bitstream bitstream)
-        throws SQLException, AuthorizeException, IOException {
+            throws IOException, SQLException, AuthorizeException {
-        byte [] citedDocumentContent = getCitedDocumentContent(context, bitstream);
-        return new ByteArrayInputStream(citedDocumentContent);
-    }
-
-    @Override
-    public Long getCitedDocumentLength(Context context, Bitstream bitstream)
-        throws SQLException, AuthorizeException, IOException {
-        byte[] citedDocumentContent = getCitedDocumentContent(context, bitstream);
-        return Long.valueOf(citedDocumentContent.length);
-    }
-
-    private byte[] getCitedDocumentContent(Context context, Bitstream bitstream)
-        throws SQLException, AuthorizeException, IOException {
         PDDocument document = new PDDocument();
         PDDocument sourceDocument = new PDDocument();
         try {
             Item item = (Item) bitstreamService.getParentObject(context, bitstream);
-            sourceDocument = sourceDocument.load(bitstreamService.retrieve(context, bitstream));
+            final InputStream inputStream = bitstreamService.retrieve(context, bitstream);
+            try {
+                sourceDocument = sourceDocument.load(inputStream);
+            } finally {
+                inputStream.close();
+            }
             PDPage coverPage = new PDPage(citationPageFormat);
             generateCoverPage(context, document, coverPage, item);
             addCoverPageToDocument(document, sourceDocument, coverPage);
+
+            //We already have the full PDF in memory, so keep it there
             try (ByteArrayOutputStream out = new ByteArrayOutputStream()) {
                 document.save(out);
-                return out.toByteArray();
+
+                byte[] data = out.toByteArray();
+                return Pair.of(new ByteArrayInputStream(data), Long.valueOf(data.length));
             }
+
         } finally {
             sourceDocument.close();
             document.close();

dspace-api/src/main/java/org/dspace/disseminate/service/CitationDocumentService.java

@@ -11,6 +11,7 @@ import java.io.IOException;
 import java.io.InputStream;
 import java.sql.SQLException;
 
+import org.apache.commons.lang3.tuple.Pair;
 import org.apache.pdfbox.pdmodel.PDPage;
 import org.apache.pdfbox.pdmodel.PDPageContentStream;
 import org.apache.pdfbox.pdmodel.font.PDFont;
@@ -83,12 +84,8 @@ public interface CitationDocumentService {
      * @throws SQLException       if database error
      * @throws AuthorizeException if authorization error
      */
-    public InputStream getCitedDocument(Context context, Bitstream bitstream)
+    public Pair<InputStream, Long> makeCitedDocument(Context context, Bitstream bitstream)
-        throws SQLException, AuthorizeException, IOException;
+            throws IOException, SQLException, AuthorizeException;
-
-    public Long getCitedDocumentLength(Context context, Bitstream bitstream)
-        throws SQLException, AuthorizeException, IOException;
-
 
     /**
      * @param page          page

dspace-server-webapp/src/main/java/org/dspace/app/rest/BitstreamRestController.java

@@ -12,6 +12,7 @@ import static org.dspace.app.rest.utils.RegexUtils.REGEX_REQUESTMAPPING_IDENTIFI
 import static org.springframework.web.bind.annotation.RequestMethod.PUT;
 
 import java.io.IOException;
+import java.io.InputStream;
 import java.sql.SQLException;
 import java.util.List;
 import java.util.UUID;
@@ -21,6 +22,7 @@ import javax.ws.rs.core.Response;
 
 import org.apache.catalina.connector.ClientAbortException;
 import org.apache.commons.lang3.StringUtils;
+import org.apache.commons.lang3.tuple.Pair;
 import org.apache.logging.log4j.Logger;
 import org.dspace.app.rest.converter.ConverterService;
 import org.dspace.app.rest.exception.DSpaceBadRequestException;
@@ -133,7 +135,9 @@ public class BitstreamRestController {
         try {
             long filesize;
             if (citationDocumentService.isCitationEnabledForBitstream(bit, context)) {
-                filesize = citationDocumentService.getCitedDocumentLength(context, bit);
+                final Pair<InputStream, Long> citedDocument = citationDocumentService.makeCitedDocument(context, bit);
+                filesize = citedDocument.getRight();
+                citedDocument.getLeft().close();
             } else {
                 filesize = bit.getSizeBytes();
             }

dspace-server-webapp/src/main/java/org/dspace/app/rest/utils/BitstreamResource.java

@@ -66,7 +66,7 @@ public class BitstreamResource extends AbstractResource {
             InputStream out;
 
             if (citationDocumentService.isCitationEnabledForBitstream(bitstream, context)) {
-                out = citationDocumentService.getCitedDocument(context, bitstream);
+                out = citationDocumentService.makeCitedDocument(context, bitstream).getLeft();
             } else {
                 out = bitstreamService.retrieve(context, bitstream);
             }