PDFBOX-6009: use one pageDictMap for each destination document and make a list of it for postprocessing

git-svn-id: https://svn.apache.org/repos/asf/pdfbox/trunk@1925612 13f79535-47bb-0310-9956-ffa450edef68

Author: THausherr

pdfbox/src/main/java/org/apache/pdfbox/multipdf/Splitter.java

@@ -82,7 +82,8 @@ public class Splitter
     private int startPage = Integer.MIN_VALUE;
     private int endPage = Integer.MAX_VALUE;
     private List<PDDocument> destinationDocuments;
-    private Map<COSDictionary, COSDictionary> pageDictMap;
+    private Map<COSDictionary, COSDictionary> pageDictMap; // map old page => new page for the current destination document
+    private List<Map<COSDictionary, COSDictionary>> pageDictMaps; // list of these maps for all destination documents
     private Map<COSDictionary, COSDictionary> structDictMap;
     private Map<COSDictionary, COSDictionary> annotDictMap;
     private Map<PDPageDestination,PDPage> destToFixMap;
@@ -129,16 +130,18 @@ public List<PDDocument> split(PDDocument document) throws IOException
         currentPageNumber = 0;
         destinationDocuments = new ArrayList<>();
         sourceDocument = document;
-        pageDictMap = new HashMap<>();
+        pageDictMaps = new ArrayList<>();
         destToFixMap = new HashMap<>();
         annotDictMap = new HashMap<>();
         idSet = new HashSet<>();
         roleSet = new HashSet<>();
 
         processPages();
 
-        for (PDDocument destinationDocument : destinationDocuments)
+        for (int i = 0; i < destinationDocuments.size(); ++i)
         {
+            PDDocument destinationDocument = destinationDocuments.get(i);
+            pageDictMap = pageDictMaps.get(i);
             cloneStructureTree(destinationDocument);
             fixDestinations(destinationDocument);
         }
@@ -180,7 +183,8 @@ private void fixDestinations(PDDocument destinationDocument)
     }
 
     /**
-     * Clone the structure tree from the source to the current destination document.
+     * Clone the structure tree from the source to the current destination document. This must be
+     * called after all pages are processed.
      *
      * @param destinationDocument
      * @throws IOException 
@@ -677,6 +681,8 @@ private void createNewDocumentIfNecessary() throws IOException
         {
             currentDestinationDocument = createNewDocument();
             destinationDocuments.add(currentDestinationDocument);
+            pageDictMap = new HashMap<>();
+            pageDictMaps.add(pageDictMap);
         }
     }