Switch Picture processing in HSLFSlideShow to be lazy-loading, to speed things up...

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1073883 13f79535-47bb-0310-9956-ffa450edef68

diff --git a/src/scratchpad/src/org/apache/poi/hslf/HSLFSlideShow.java b/src/scratchpad/src/org/apache/poi/hslf/HSLFSlideShow.java
index 22a3b8abaa418519d90b4a89718232ba0f7206dc..65954a775f91e4d26b0a84560e3b244c9bde0ab0 100644 (file)
--- a/src/scratchpad/src/org/apache/poi/hslf/HSLFSlideShow.java
+++ b/src/scratchpad/src/org/apache/poi/hslf/HSLFSlideShow.java
@@ -174,9 +174,6 @@ public final class HSLFSlideShow extends POIDocument {
 
                // Look for any other streams
                readOtherStreams();
-
-               // Look for Picture Streams:
-               readPictures();
        }
        /**
         * Constructs a new, empty, Powerpoint document.
@@ -309,7 +306,8 @@ public final class HSLFSlideShow extends POIDocument {
        }
 
        /**
-        * Find and read in pictures contained in this presentation
+        * Find and read in pictures contained in this presentation.
+        * This is lazily called as and when we want to touch pictures.
         */
        private void readPictures() throws IOException {
         _pictures = new ArrayList<PictureData>();
@@ -472,6 +470,9 @@ public final class HSLFSlideShow extends POIDocument {
 
 
         // Write any pictures, into another stream
+        if(_pictures == null) {
+           readPictures();
+        }
         if (_pictures.size() > 0) {
             ByteArrayOutputStream pict = new ByteArrayOutputStream();
             for (PictureData p : _pictures) {
@@ -526,15 +527,24 @@ public final class HSLFSlideShow extends POIDocument {
      * @return offset of this picture in the Pictures stream
         */
        public int addPicture(PictureData img) {
-               int offset = 0;
-
-        if(_pictures.size() > 0){
-            PictureData prev = _pictures.get(_pictures.size() - 1);
-            offset = prev.getOffset() + prev.getRawData().length + 8;
-        }
-        img.setOffset(offset);
-        _pictures.add(img);
-        return offset;
+          // Process any existing pictures if we haven't yet
+          if(_pictures == null) {
+         try {
+            readPictures();
+         } catch(IOException e) {
+            throw new CorruptPowerPointFileException(e.getMessage());
+         }
+          }
+          
+          // Add the new picture in
+      int offset = 0;
+          if(_pictures.size() > 0) {
+             PictureData prev = _pictures.get(_pictures.size() - 1);
+             offset = prev.getOffset() + prev.getRawData().length + 8;
+          }
+          img.setOffset(offset);
+          _pictures.add(img);
+          return offset;
    }
 
        /* ******************* fetching methods follow ********************* */
@@ -563,6 +573,14 @@ public final class HSLFSlideShow extends POIDocument {
         *  presentation doesn't contain pictures.
         */
        public PictureData[] getPictures() {
+          if(_pictures == null) {
+             try {
+                readPictures();
+             } catch(IOException e) {
+                throw new CorruptPowerPointFileException(e.getMessage());
+             }
+          }
+          
                return _pictures.toArray(new PictureData[_pictures.size()]);
        }