in src/main/java/com/twitter/whiskey/net/SpdyCodecUtil.java [349:360]
static void validateHeaderValue(CharSequence value) {
if (value == null) {
throw new NullPointerException("value");
}
for (int i = 0; i < value.length(); i ++) {
char c = value.charAt(i);
if (c == 0) {
throw new IllegalArgumentException(
"value contains null character: " + value);
}
}
}