codacy: No need to call String.valueOf to append to a string.

src/main/java/com/owncloud/android/ui/adapter/LocalFileListAdapter.java

@@ -248,7 +248,7 @@ public class LocalFileListAdapter extends RecyclerView.Adapter<RecyclerView.View
             if (MimeTypeUtil.isImage(file)) {
                 // Thumbnail in Cache?
                 Bitmap thumbnail = ThumbnailsCacheManager.getBitmapFromDiskCache(
-                        ThumbnailsCacheManager.PREFIX_THUMBNAIL + String.valueOf(file.hashCode())
+                        ThumbnailsCacheManager.PREFIX_THUMBNAIL + file.hashCode()
                 );
                 if (thumbnail != null) {
                     thumbnailView.setImageBitmap(thumbnail);

src/main/java/com/owncloud/android/ui/adapter/OCFileListAdapter.java

@@ -380,7 +380,7 @@ public class OCFileListAdapter extends RecyclerView.Adapter<RecyclerView.ViewHol
             if ((MimeTypeUtil.isImage(file) || MimeTypeUtil.isVideo(file)) && file.getRemoteId() != null) {
                 // Thumbnail in cache?
                 Bitmap thumbnail = ThumbnailsCacheManager.getBitmapFromDiskCache(
-                        ThumbnailsCacheManager.PREFIX_THUMBNAIL + String.valueOf(file.getRemoteId())
+                        ThumbnailsCacheManager.PREFIX_THUMBNAIL + file.getRemoteId()
                 );
 
                 if (thumbnail != null && !file.needsUpdateThumbnail()) {

src/main/java/com/owncloud/android/ui/adapter/TrashbinListAdapter.java

@@ -211,7 +211,7 @@ public class TrashbinListAdapter extends RecyclerView.Adapter<RecyclerView.ViewH
             if ((MimeTypeUtil.isImage(file) || MimeTypeUtil.isVideo(file)) && file.getRemoteId() != null) {
                 // Thumbnail in cache?
                 Bitmap thumbnail = ThumbnailsCacheManager.getBitmapFromDiskCache(
-                        ThumbnailsCacheManager.PREFIX_THUMBNAIL + String.valueOf(file.getRemoteId())
+                        ThumbnailsCacheManager.PREFIX_THUMBNAIL + file.getRemoteId()
                 );
 
                 if (thumbnail != null) {

src/main/java/com/owncloud/android/utils/BitmapUtils.java

@@ -289,7 +289,7 @@ public final class BitmapUtils {
 
         // Splitting evenly the string
         for (int i = 0; i < hash.length(); i++) {
-            result[i % modulo] = result[i % modulo] + String.valueOf(Integer.parseInt(hash.substring(i, i + 1), 16));
+            result[i % modulo] = result[i % modulo] + Integer.parseInt(hash.substring(i, i + 1), 16);
         }
 
         // Converting our data into a usable rgb format