AsciiHeadersEncoder Class — netty Architecture

Source Code

codec-base/src/main/java/io/netty/handler/codec/AsciiHeadersEncoder.java lines 28–121

public final class AsciiHeadersEncoder {

    /**
     * The separator characters to insert between a header name and a header value.
     */
    public enum SeparatorType {
        /**
         * {@code ':'}
         */
        COLON,
        /**
         * {@code ': '}
         */
        COLON_SPACE,
    }

    /**
     * The newline characters to insert between header entries.
     */
    public enum NewlineType {
        /**
         * {@code '\n'}
         */
        LF,
        /**
         * {@code '\r\n'}
         */
        CRLF
    }

    private final ByteBuf buf;
    private final SeparatorType separatorType;
    private final NewlineType newlineType;

    public AsciiHeadersEncoder(ByteBuf buf) {
        this(buf, SeparatorType.COLON_SPACE, NewlineType.CRLF);
    }

    public AsciiHeadersEncoder(ByteBuf buf, SeparatorType separatorType, NewlineType newlineType) {
        this.buf = ObjectUtil.checkNotNull(buf, "buf");
        this.separatorType = ObjectUtil.checkNotNull(separatorType, "separatorType");
        this.newlineType = ObjectUtil.checkNotNull(newlineType, "newlineType");
    }

    public void encode(Entry<CharSequence, CharSequence> entry) {
        final CharSequence name = entry.getKey();
        final CharSequence value = entry.getValue();
        final ByteBuf buf = this.buf;
        final int nameLen = name.length();
        final int valueLen = value.length();
        final int entryLen = nameLen + valueLen + 4;
        int offset = buf.writerIndex();
        buf.ensureWritable(entryLen);
        writeAscii(buf, offset, name);
        offset += nameLen;

        switch (separatorType) {
            case COLON:
                buf.setByte(offset ++, ':');
                break;
            case COLON_SPACE:
                buf.setByte(offset ++, ':');
                buf.setByte(offset ++, ' ');
                break;
            default:
                throw new Error("Unexpected separator type: " + separatorType);
        }

        writeAscii(buf, offset, value);
        offset += valueLen;

        switch (newlineType) {
            case LF:
                buf.setByte(offset ++, '\n');
                break;
            case CRLF:
                buf.setByte(offset ++, '\r');
                buf.setByte(offset ++, '\n');
                break;
            default:
                throw new Error("Unexpected newline type: " + newlineType);