Handle external cache deletion

3 files changed, 43 insertions, 15 deletions

diff --git a/org.eclipse.userstorage/src/org/eclipse/userstorage/internal/Storage.java b/org.eclipse.userstorage/src/org/eclipse/userstorage/internal/Storage.java
index 53f6512..2d617b2 100644
--- a/org.eclipse.userstorage/src/org/eclipse/userstorage/internal/Storage.java
+++ b/org.eclipse.userstorage/src/org/eclipse/userstorage/internal/Storage.java
@@ -14,6 +14,7 @@ import org.eclipse.userstorage.IBlob;
 import org.eclipse.userstorage.IStorage;
 import org.eclipse.userstorage.IStorageService;
 import org.eclipse.userstorage.StorageFactory;
+import org.eclipse.userstorage.internal.util.IOUtil;
 import org.eclipse.userstorage.internal.util.IOUtil.TeeInputStream;
 import org.eclipse.userstorage.internal.util.StringUtil;
 import org.eclipse.userstorage.spi.ICredentialsProvider;
@@ -234,27 +235,49 @@ public final class Storage implements IStorage
 
   public InputStream retrieveBlob(String key, Map<String, String> properties) throws IOException, NoServiceException
   {
-    StorageService service = getServiceSafe();
-    InputStream contents = service.retrieveBlob(credentialsProvider, applicationToken, key, properties, cache != null);
-
+    InputStream cacheStream = null;
     if (cache != null)
     {
-      if (contents == Blob.NOT_MODIFIED)
+      try
       {
-        return cache.internalGetInputStream(applicationToken, key);
+        cacheStream = cache.internalGetInputStream(applicationToken, key);
       }
+      catch (IOException ex)
+      {
+        Activator.log(ex);
+      }
+    }
+
+    try
+    {
+      StorageService service = getServiceSafe();
+      InputStream contents = service.retrieveBlob(credentialsProvider, applicationToken, key, properties, cacheStream != null);
 
-      if (contents == null)
+      if (cacheStream != null)
       {
-        cache.internalDelete(applicationToken, key);
-        return null;
+        if (contents == Blob.NOT_MODIFIED)
+        {
+          InputStream cacheStreamResult = cacheStream;
+          cacheStream = null; // Avoid closing the result stream in the finally block
+          return cacheStreamResult;
+        }
+
+        if (contents == null)
+        {
+          cache.internalDelete(applicationToken, key);
+          return null;
+        }
+
+        OutputStream output = cache.internalGetOutputStream(applicationToken, key, properties);
+        return new TeeInputStream(contents, output);
       }
 
-      OutputStream output = cache.internalGetOutputStream(applicationToken, key, properties);
-      return new TeeInputStream(contents, output);
+      return contents;
+    }
+    finally
+    {
+      IOUtil.closeSilent(cacheStream);
     }
-
-    return contents;
   }
 
   public boolean updateBlob(String key, Map<String, String> properties, InputStream in) throws IOException, ConflictException, NoServiceException
diff --git a/org.eclipse.userstorage/src/org/eclipse/userstorage/spi/StorageCache.java b/org.eclipse.userstorage/src/org/eclipse/userstorage/spi/StorageCache.java
index 609e4f9..1c390d1 100644
--- a/org.eclipse.userstorage/src/org/eclipse/userstorage/spi/StorageCache.java
+++ b/org.eclipse.userstorage/src/org/eclipse/userstorage/spi/StorageCache.java
@@ -122,8 +122,8 @@ public abstract class StorageCache extends InternalStorageCache
    *        must not be <code>null</code>.<p>
    * @param key the {@link IBlob#getKey() key} for which to return the contents stream,
    *        must not be <code>null</code>.<p>
-   * @return an {@link InputStream} that represents the cached contents of this blob, never <code>null</code>.<p>
-   * @throws IOException if local I/O was unsuccessful, including the case that the contents disappeared from this cache.<p>
+   * @return an {@link InputStream} that represents the cached contents of the blob, or <code>null</code> if the blob does not exist in this cache.<p>
+   * @throws IOException if local I/O was unsuccessful.<p>
    */
   @Override
   protected abstract InputStream getInputStream(String applicationToken, String key) throws IOException;
diff --git a/org.eclipse.userstorage/src/org/eclipse/userstorage/util/FileStorageCache.java b/org.eclipse.userstorage/src/org/eclipse/userstorage/util/FileStorageCache.java
index ec8c0c5..644afae 100644
--- a/org.eclipse.userstorage/src/org/eclipse/userstorage/util/FileStorageCache.java
+++ b/org.eclipse.userstorage/src/org/eclipse/userstorage/util/FileStorageCache.java
@@ -173,7 +173,12 @@ public class FileStorageCache extends StorageCache
   protected InputStream getInputStream(String applicationToken, String key) throws IOException
   {
     File file = getFile(applicationToken, key, null);
-    return new FileInputStream(file);
+    if (file.isFile())
+    {
+      return new FileInputStream(file);
+    }
+
+    return null;
   }
 
   /**