| // Copyright (c) 1999-2004 Brian Wellington (bwelling@xbill.org) |
| |
| package org.xbill.DNS; |
| |
| /** |
| * Constants and functions relating to DNS classes. This is called DClass |
| * to avoid confusion with Class. |
| * |
| * @author Brian Wellington |
| */ |
| |
| public final class DClass { |
| |
| /** Internet */ |
| public static final int IN = 1; |
| |
| /** Chaos network (MIT) */ |
| public static final int CH = 3; |
| |
| /** Chaos network (MIT, alternate name) */ |
| public static final int CHAOS = 3; |
| |
| /** Hesiod name server (MIT) */ |
| public static final int HS = 4; |
| |
| /** Hesiod name server (MIT, alternate name) */ |
| public static final int HESIOD = 4; |
| |
| /** Special value used in dynamic update messages */ |
| public static final int NONE = 254; |
| |
| /** Matches any class */ |
| public static final int ANY = 255; |
| |
| private static class DClassMnemonic extends Mnemonic { |
| public |
| DClassMnemonic() { |
| super("DClass", CASE_UPPER); |
| setPrefix("CLASS"); |
| } |
| |
| public void |
| check(int val) { |
| DClass.check(val); |
| } |
| } |
| |
| private static Mnemonic classes = new DClassMnemonic(); |
| |
| static { |
| classes.add(IN, "IN"); |
| classes.add(CH, "CH"); |
| classes.addAlias(CH, "CHAOS"); |
| classes.add(HS, "HS"); |
| classes.addAlias(HS, "HESIOD"); |
| classes.add(NONE, "NONE"); |
| classes.add(ANY, "ANY"); |
| } |
| |
| private |
| DClass() {} |
| |
| /** |
| * Checks that a numeric DClass is valid. |
| * @throws InvalidDClassException The class is out of range. |
| */ |
| public static void |
| check(int i) { |
| if (i < 0 || i > 0xFFFF) |
| throw new InvalidDClassException(i); |
| } |
| |
| /** |
| * Converts a numeric DClass into a String |
| * @return The canonical string representation of the class |
| * @throws InvalidDClassException The class is out of range. |
| */ |
| public static String |
| string(int i) { |
| return classes.getText(i); |
| } |
| |
| /** |
| * Converts a String representation of a DClass into its numeric value |
| * @return The class code, or -1 on error. |
| */ |
| public static int |
| value(String s) { |
| return classes.getValue(s); |
| } |
| |
| } |