// SPDX-License-Identifier: BSD-3-Clause

// Copyright (c) 1999-2004 Brian Wellington (bwelling@xbill.org)

package org.xbill.DNS;

/**

* Constants and functions relating to DNS opcodes

*

* @author Brian Wellington

*/

public final class Opcode {

/** A standard query */

public static final int QUERY = 0;

/** An inverse query (deprecated) */

public static final int IQUERY = 1;

/** A server status request (not used) */

public static final int STATUS = 2;

/** A message from a primary to a secondary server to initiate a zone transfer */

@SuppressWarnings("java:S1845")

public static final int NOTIFY = 4;

/** A dynamic update message */

public static final int UPDATE = 5;

/**

* DNS Stateful Operations (DSO).

*

* @see <a href="https://datatracker.ietf.org/doc/html/rfc8490">RFC 8490</a>

*/

public static final int DSO = 6;

private static final Mnemonic opcodes = new Mnemonic("DNS Opcode", Mnemonic.CASE_UPPER);

static {

opcodes.setMaximum(0xF);

opcodes.setPrefix("RESERVED");

opcodes.setNumericAllowed(true);

opcodes.add(QUERY, "QUERY");

opcodes.add(IQUERY, "IQUERY");

opcodes.add(STATUS, "STATUS");

opcodes.add(NOTIFY, "NOTIFY");

opcodes.add(UPDATE, "UPDATE");

opcodes.add(DSO, "DSO");

}

private Opcode() {}

/** Converts a numeric Opcode into a String */

public static String string(int i) {

return opcodes.getText(i);

}

/** Converts a String representation of an Opcode into its numeric value */

public static int value(String s) {

return opcodes.getValue(s);

}

}