Class GzipOutputFilter

java/org/apache/coyote/http11/filters/GzipOutputFilter.java:34–191

Gzip output filter that compresses response data using the GZIP algorithm.

 * Gzip output filter that compresses response data using the GZIP algorithm.
 */
public class GzipOutputFilter implements OutputFilter {

    /**
     * Logger for this filter.
     */
    protected static final Log log = LogFactory.getLog(GzipOutputFilter.class);
    private static final StringManager sm = StringManager.getManager(GzipOutputFilter.class);

    /**
     * Constructs a new GzipOutputFilter.
     */
    public GzipOutputFilter() {
    }


    // ----------------------------------------------------- Instance Variables

    /**
     * Next buffer in the pipeline.
     */
    protected HttpOutputBuffer buffer;


    /**
     * Compression output stream.
     */
    protected GZIPOutputStream compressionStream = null;


    /**
     * Fake internal output stream.
     */
    protected final OutputStream fakeOutputStream = new FakeOutputStream();


    // --------------------------------------------------- OutputBuffer Methods

    @Override
    public int doWrite(ByteBuffer chunk) throws IOException {
        if (compressionStream == null) {
            compressionStream = new GZIPOutputStream(fakeOutputStream, true);
        }
        int len = chunk.remaining();
        if (chunk.hasArray()) {
            compressionStream.write(chunk.array(), chunk.arrayOffset() + chunk.position(), len);
            chunk.position(chunk.position() + len);
        } else {
            byte[] bytes = new byte[len];
            chunk.get(bytes);
            compressionStream.write(bytes, 0, len);
        }
        return len;
    }


    @Override
    public long getBytesWritten() {
        return buffer.getBytesWritten();