diff --git a/src/main/java/azgracompress/compression/ImageCompressor.java b/src/main/java/azgracompress/compression/ImageCompressor.java
index 5728d6acece9024c4718a72d6086610e67193e7e..191fb9ab460af548207943041615eb1d14233eae 100644
--- a/src/main/java/azgracompress/compression/ImageCompressor.java
+++ b/src/main/java/azgracompress/compression/ImageCompressor.java
@@ -67,7 +67,7 @@ public class ImageCompressor extends CompressorDecompressorBase {
         return true;
     }
 
-    public int streamCompress(OutputStream outputStream) {
+    public int streamCompress(final OutputStream outputStream) {
         assert (false) : "Not implemented!";
         return -1;
     }