HttpContentDecompressor Class — netty Architecture

Source Code

codec-http/src/main/java/io/netty/handler/codec/http/HttpContentDecompressor.java lines 42–145

public class HttpContentDecompressor extends HttpContentDecoder {

    private final boolean strict;
    private final int maxAllocation;

    /**
     * Create a new {@link HttpContentDecompressor} in non-strict mode.
     * @deprecated
     *            Use {@link HttpContentDecompressor#HttpContentDecompressor(int)}.
     */
    @Deprecated
    public HttpContentDecompressor() {
        this(false, 0);
    }

    /**
     * Create a new {@link HttpContentDecompressor} in non-strict mode.
     * @param maxAllocation
     *            Maximum size of the decompression buffer. Must be >= 0. If zero, maximum size is not limited.
     */
    public HttpContentDecompressor(int maxAllocation) {
        this(false, maxAllocation);
    }

    /**
     * Create a new {@link HttpContentDecompressor}.
     *
     * @param strict    if {@code true} use strict handling of deflate if used, otherwise handle it in a
     *                  more lenient fashion.
     * @deprecated
     *            Use {@link HttpContentDecompressor#HttpContentDecompressor(boolean, int)}.
     */
    @Deprecated
    public HttpContentDecompressor(boolean strict) {
        this(strict, 0);
    }

    /**
     * Create a new {@link HttpContentDecompressor}.
     *
     * @param strict    if {@code true} use strict handling of deflate if used, otherwise handle it in a
     *                  more lenient fashion.
     * @param maxAllocation
     *             Maximum size of the decompression buffer. Must be >= 0. If zero, maximum size is not limited.
     */
    public HttpContentDecompressor(boolean strict, int maxAllocation) {
        this.strict = strict;
        this.maxAllocation = checkPositiveOrZero(maxAllocation, "maxAllocation");
    }

    @Override
    protected EmbeddedChannel newContentDecoder(String contentEncoding) throws Exception {
        Channel channel = ctx.channel();
        if (GZIP.contentEqualsIgnoreCase(contentEncoding) ||
            X_GZIP.contentEqualsIgnoreCase(contentEncoding)) {
            return EmbeddedChannel.builder()
                    .channelId(channel.id())
                    .hasDisconnect(channel.metadata().hasDisconnect())
                    .config(channel.config())
                    .handlers(ZlibCodecFactory.newZlibDecoder(ZlibWrapper.GZIP, maxAllocation))
                    .build();
        }
        if (DEFLATE.contentEqualsIgnoreCase(contentEncoding) ||
            X_DEFLATE.contentEqualsIgnoreCase(contentEncoding)) {
            final ZlibWrapper wrapper = strict ? ZlibWrapper.ZLIB : ZlibWrapper.ZLIB_OR_NONE;
            // To be strict, 'deflate' means ZLIB, but some servers were not implemented correctly.
            return EmbeddedChannel.builder()
                    .channelId(channel.id())
                    .hasDisconnect(channel.metadata().hasDisconnect())
                    .config(channel.config())
                    .handlers(ZlibCodecFactory.newZlibDecoder(wrapper, maxAllocation))
                    .build();
        }
        if (Brotli.isAvailable() && BR.contentEqualsIgnoreCase(contentEncoding)) {
            return EmbeddedChannel.builder()
                    .channelId(channel.id())
                    .hasDisconnect(channel.metadata().hasDisconnect())
                    .config(channel.config())
                    .handlers(new BrotliDecoder())
                    .build();
        }