src/share/classes/com/sun/imageio/plugins/png/PNGImageReader.java

@@ -637,11 +637,11 @@
     private void parse_zTXt_chunk(int chunkLength) throws IOException {
         String keyword = readNullTerminatedString("ISO-8859-1", 80);
         metadata.zTXt_keyword.add(keyword);
 
         int method = stream.readUnsignedByte();
-        metadata.zTXt_compressionMethod.add(new Integer(method));
+        metadata.zTXt_compressionMethod.add(method);
 
         byte[] b = new byte[chunkLength - keyword.length() - 2];
         stream.readFully(b);
         metadata.zTXt_text.add(new String(inflate(b), "ISO-8859-1"));
     }