Updates to ThumbnailLoader and ThumbnailService

ThumbnailLoader calls new API, checks if image has pyramids and can determine what state a thumbnail is in if it is missing
ThumbnailBean has additional simple load method that only returns a thumbnail if is available, otherwise returns an empty array

components/blitz/resources/omero/api/ThumbnailStore.ice

@@ -90,7 +90,8 @@ module omero {
                  * in the on-disk cache it will be returned directly,
                  * otherwise it will be created as in
                  * {@link #getThumbnailDirect}, placed in the on-disk
-                 * cache and returned.
+                 * cache and returned. If the thumbnail is missing, a clock will
+                 * be returned to signify that the thumbnail is yet to be generated.
                  *
                  * @param sizeX the X-axis width of the thumbnail.
                  *              <code>null</code> specifies the default size
@@ -112,6 +113,35 @@ module omero {
                  */
                 idempotent Ice::ByteSeq getThumbnail(omero::RInt sizeX, omero::RInt sizeY) throws ServerError;
 
+                /**
+                 * Retrieves a thumbnail for a pixels set using a given set of
+                 * rendering settings (RenderingDef). If the thumbnail exists
+                 * in the on-disk cache it will be returned directly,
+                 * otherwise it will be created as in
+                 * {@link #getThumbnailDirect}, placed in the on-disk
+                 * cache and returned. If the thumbnail is still to be generated, an empty array will
+                 * be returned.
+                 *
+                 * @param sizeX the X-axis width of the thumbnail.
+                 *              <code>null</code> specifies the default size
+                 *              of 48.
+                 * @param sizeY the Y-axis width of the thumbnail.
+                 *              <code>null</code> specifies the default size
+                 *              of 48.
+                 * @throws ApiUsageException
+                 *             if:
+                 *             <ul>
+                 *             <li><code>sizeX</code> > pixels.sizeX</li>
+                 *             <li><code>sizeX</code> is negative</li>
+                 *             <li><code>sizeY</code> > pixels.sizeY</li>
+                 *             <li><code>sizeY</code> is negative</li>
+                 *             <li>{@link #setPixelsId} has not yet been called</li>
+                 *             </ul>
+                 * @return a JPEG thumbnail byte buffer
+                 * @see #getThumbnailDirect
+                 */
+                idempotent Ice::ByteSeq getThumbnailWithoutDefault(omero::RInt sizeX, omero::RInt sizeY) throws ServerError;
+
                 /**
                  * Retrieves a number of thumbnails for pixels sets using
                  * given sets of rendering settings (RenderingDef). If the

components/blitz/src/ome/services/blitz/impl/ThumbnailStoreI.java

@@ -16,6 +16,7 @@
 import omero.api.AMD_ThumbnailStore_createThumbnailsByLongestSideSet;
 import omero.api.AMD_ThumbnailStore_getRenderingDefId;
 import omero.api.AMD_ThumbnailStore_getThumbnail;
+import omero.api.AMD_ThumbnailStore_getThumbnailWithoutDefault;
 import omero.api.AMD_ThumbnailStore_getThumbnailByLongestSide;
 import omero.api.AMD_ThumbnailStore_getThumbnailByLongestSideDirect;
 import omero.api.AMD_ThumbnailStore_getThumbnailByLongestSideSet;
@@ -126,6 +127,12 @@ public void getThumbnail_async(AMD_ThumbnailStore_getThumbnail __cb,
 
     }
 
+    public void getThumbnailWithoutDefault_async(AMD_ThumbnailStore_getThumbnailWithoutDefault __cb,
+            RInt sizeX, RInt sizeY, Current __current) throws ServerError {
+        callInvokerOnRawArgs(__cb, __current, sizeX, sizeY);
+
+    }
+
     public void resetDefaults_async(AMD_ThumbnailStore_resetDefaults __cb,
             Current __current) throws ServerError {
         callInvokerOnRawArgs(__cb, __current);

components/common/src/ome/api/ThumbnailStore.java

@@ -105,6 +105,35 @@ public interface ThumbnailStore extends StatefulServiceInterface {
      * @see #getThumbnailDirect(Integer, Integer)
      */
     public byte[] getThumbnail(Integer sizeX, Integer sizeY);
+
+    /**
+    * Retrieves a thumbnail for a pixels set using a given set of
+    * rendering settings (RenderingDef). If the thumbnail exists
+    * in the on-disk cache it will be returned directly,
+    * otherwise it will be created as in
+    * {@link #getThumbnailDirect}, placed in the on-disk
+    * cache and returned. If the thumbnail is still to be generated, an empty array will
+    * be returned.
+    *
+    * @param sizeX the X-axis width of the thumbnail.
+    *              <code>null</code> specifies the default size
+    *              of 48.
+    * @param sizeY the Y-axis width of the thumbnail.
+    *              <code>null</code> specifies the default size
+    *              of 48.
+    * @throws ApiUsageException
+    *             if:
+    *             <ul>
+    *             <li><code>sizeX</code> > pixels.sizeX</li>
+    *             <li><code>sizeX</code> is negative</li>
+    *             <li><code>sizeY</code> > pixels.sizeY</li>
+    *             <li><code>sizeY</code> is negative</li>
+    *             <li>{@link #setPixelsId} has not yet been called</li>
+    *             </ul>
+    * @return a JPEG thumbnail byte buffer
+    * @see #getThumbnailDirect
+    */
+    public byte[] getThumbnailWithoutDefault(Integer sizeX, Integer sizeY);
 
     /**
      * Retrieves a number of thumbnails for pixels sets using given sets of