public static <T> void mergeFrom(InputStream in, T message, Schema<T> schema)
            throws IOException
    {
        mergeFrom(in, message, schema, DEFAULT_INPUT_FACTORY);
    }
Merges the {@code message} from the {@link InputStream} using the given {@code schema}.
protostuff-xml/src/main/java/io/protostuff/XmlIOUtil.java