#vulnerable code 
                                @Test
    public void testDecodePadMarkerIndex2() throws UnsupportedEncodingException {
        assertEquals("A", new String(Base64.decodeBase64("QQ==".getBytes("UTF-8"))));
    } 
                            #location 3 
                            #vulnerability type NULL_DEREFERENCE
#fixed code
                                @Test
    public void testDecodePadMarkerIndex2() throws UnsupportedEncodingException {
        assertEquals("A", new String(Base64.decodeBase64("QQ==".getBytes(Charsets.UTF_8))));
    }