// otherwise return a 304 (not modified).
	ifModifiedSinceHeader := r.Header.Get(xhttp.IfModifiedSince)
	if ifModifiedSinceHeader != "" {
		if givenTime, err := amztime.ParseHeader(ifModifiedSinceHeader); err == nil {
			if !ifModifiedSince(objInfo.ModTime, givenTime) {
				// If the object is not modified since the specified time.
				writeHeadersPrecondition(w, objInfo)

    public boolean getUseCaches() {
        return connection.getUseCaches();
    }

    @Override
    public void setIfModifiedSince(final long ifModifiedSince) {
        connection.setIfModifiedSince(ifModifiedSince);
        this.ifModifiedSince = ifModifiedSince;
    }

    @Override
    public long getIfModifiedSince() {
        return connection.getIfModifiedSince();
    }

    @Override

    public boolean getUseCaches() {
        return this.connection.getUseCaches();
    }

    @Override
    public void setIfModifiedSince(final long ifModifiedSince) {
        this.connection.setIfModifiedSince(ifModifiedSince);
        this.ifModifiedSince = ifModifiedSince;
    }

    @Override
    public long getIfModifiedSince() {
        return this.connection.getIfModifiedSince();
    }

    @Override

	Range              = "Range"
)

// Non standard S3 HTTP response constants
const (
	XCache       = "X-Cache"
	XCacheLookup = "X-Cache-Lookup"
)

// Standard S3 HTTP request constants
const (
	IfModifiedSince   = "If-Modified-Since"
	IfUnmodifiedSince = "If-Unmodified-Since"
	IfMatch           = "If-Match"
	IfNoneMatch       = "If-None-Match"

	// Request tags used in GetObjectAttributes
	Checksum     = "Checksum"