BlobUtils { static File getStorageLocation(File storageDir, BlobKey key) { return new File(getCacheDirectory(storageDir), BLOB_FILE_PREFIX + key.toString()); } private  BlobUtils();   }
@Test(expected = Exception.class) public void testExceptionOnCreateCacheDirectoryFailure() { BlobUtils.getStorageLocation(new File(blobUtilsTestDirectory, CANNOT_CREATE_THIS), mock(BlobKey.class)); }