13742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman/**
23742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman *
33742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman */
43742d9db8b6edb10627b0f89336cca5249f1d15aManuel Romanpackage javax.jmdns.impl.constants;
53742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
63742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman/**
73742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman * DNS label.
83742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman *
93742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman * @author Arthur van Hoff, Jeff Sonstein, Werner Randelshofer, Pierre Frisch, Rick Blair
103742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman */
113742d9db8b6edb10627b0f89336cca5249f1d15aManuel Romanpublic enum DNSLabel {
123742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    /**
133742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * This is unallocated.
143742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     */
153742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    Unknown("", 0x80),
163742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    /**
173742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * Standard label [RFC 1035]
183742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     */
193742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    Standard("standard label", 0x00),
203742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    /**
213742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * Compressed label [RFC 1035]
223742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     */
233742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    Compressed("compressed label", 0xC0),
243742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    /**
253742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * Extended label [RFC 2671]
263742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     */
273742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    Extended("extended label", 0x40);
283742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
293742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    /**
303742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * DNS label types are encoded on the first 2 bits
313742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     */
323742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    static final int     LABEL_MASK     = 0xC0;
333742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    static final int     LABEL_NOT_MASK = 0x3F;
343742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
353742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    private final String _externalName;
363742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
373742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    private final int    _index;
383742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
393742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    DNSLabel(String name, int index) {
403742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman        _externalName = name;
413742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman        _index = index;
423742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    }
433742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
443742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    /**
453742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * Return the string representation of this type
463742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     *
473742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * @return String
483742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     */
493742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    public String externalName() {
503742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman        return _externalName;
513742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    }
523742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
533742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    /**
543742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * Return the numeric value of this type
553742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     *
563742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * @return String
573742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     */
583742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    public int indexValue() {
593742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman        return _index;
603742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    }
613742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
623742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    /**
633742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * @param index
643742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * @return label
653742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     */
663742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    public static DNSLabel labelForByte(int index) {
673742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman        int maskedIndex = index & LABEL_MASK;
683742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman        for (DNSLabel aLabel : DNSLabel.values()) {
693742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman            if (aLabel._index == maskedIndex) return aLabel;
703742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman        }
713742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman        return Unknown;
723742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    }
733742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
743742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    /**
753742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * @param index
763742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     * @return masked value
773742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman     */
783742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    public static int labelValue(int index) {
793742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman        return index & LABEL_NOT_MASK;
803742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    }
813742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
823742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    @Override
833742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    public String toString() {
843742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman        return this.name() + " index " + this.indexValue();
853742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman    }
863742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman
873742d9db8b6edb10627b0f89336cca5249f1d15aManuel Roman}
88