ReadOnlyValueIterator Class — netty Architecture

Source Code

codec-http2/src/main/java/io/netty/handler/codec/http2/ReadOnlyHttp2Headers.java lines 786–838

    private final class ReadOnlyValueIterator implements Iterator<CharSequence> {
        private int i;
        private final int nameHash;
        private final CharSequence name;
        private AsciiString[] current = pseudoHeaders.length != 0 ? pseudoHeaders : otherHeaders;
        private AsciiString next;

        ReadOnlyValueIterator(CharSequence name) {
            nameHash = AsciiString.hashCode(name);
            this.name = name;
            calculateNext();
        }

        @Override
        public boolean hasNext() {
            return next != null;
        }

        @Override
        public CharSequence next() {
            if (!hasNext()) {
                throw new NoSuchElementException();
            }
            CharSequence current = next;
            calculateNext();
            return current;
        }

        @Override
        public void remove() {
            throw new UnsupportedOperationException("read only");
        }

        private void calculateNext() {
            for (; i < current.length; i += 2) {
                AsciiString roName = current[i];
                if (roName.hashCode() == nameHash && roName.contentEqualsIgnoreCase(name)) {
                    if (i + 1 < current.length) {
                        next = current[i + 1];
                        i += 2;
                    }
                    return;
                }
            }
            if (current == pseudoHeaders) {
                i = 0;
                current = otherHeaders;
                calculateNext();
            } else {
                next = null;
            }
        }
    }