#vulnerable code 
                                @Test
    public void testDecodeWithArgs() throws IOException {
        initExpectations();

        Packet packet = decoder.decodePacket("6:::12+[\"woot\",\"wa\"]", null);
        Assert.assertEquals(PacketType.ACK, packet.getType());
        Assert.assertEquals(12, (long)packet.getAckId());
//        Assert.assertEquals(Arrays.<Object>asList("woot", "wa"), packet.getArgs());
    } 
                            #location 6 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Test
    public void testDecodeWithArgs() throws IOException {
        initExpectations();

        Packet packet = decoder.decodePackets(Unpooled.copiedBuffer("6:::12+[\"woot\",\"wa\"]", CharsetUtil.UTF_8), null);
        Assert.assertEquals(PacketType.ACK, packet.getType());
        Assert.assertEquals(12, (long)packet.getAckId());
//        Assert.assertEquals(Arrays.<Object>asList("woot", "wa"), packet.getArgs());
    }