001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017
018package org.apache.commons.net.smtp;
019
020/***
021 * SMTPCommand stores a set of constants for SMTP command codes.  To interpret
022 * the meaning of the codes, familiarity with RFC 821 is assumed.
023 * The mnemonic constant names are transcriptions from the code descriptions
024 * of RFC 821.  For those who think in terms of the actual SMTP commands,
025 * a set of constants such as {@link #HELO  HELO } are provided
026 * where the constant name is the same as the SMTP command.
027 * <p>
028 * <p>
029 ***/
030
031public final class SMTPCommand
032{
033
034
035    public static final int HELO = 0;
036    public static final int MAIL = 1;
037    public static final int RCPT = 2;
038    public static final int DATA = 3;
039    public static final int SEND = 4;
040    public static final int SOML = 5;
041    public static final int SAML = 6;
042    public static final int RSET = 7;
043    public static final int VRFY = 8;
044    public static final int EXPN = 9;
045    public static final int HELP = 10;
046    public static final int NOOP = 11;
047    public static final int TURN = 12;
048    public static final int QUIT = 13;
049
050    /** 
051     * The authorization command
052     * @since 3.0 
053     */
054    public static final int AUTH = 14 ;
055
056    /** 
057     * The extended hello command
058     * @since 3.0 
059     */
060    public static final int EHLO = 15 ;
061
062    private static final int _NEXT_ = EHLO + 1; // update as necessary when adding new entries
063
064    public static final int HELLO = HELO;
065    public static final int LOGIN = HELO;
066    public static final int MAIL_FROM = MAIL;
067    public static final int RECIPIENT = RCPT;
068    public static final int SEND_MESSAGE_DATA = DATA;
069    public static final int SEND_FROM = SEND;
070    public static final int SEND_OR_MAIL_FROM = SOML;
071    public static final int SEND_AND_MAIL_FROM = SAML;
072    public static final int RESET = RSET;
073    public static final int VERIFY = VRFY;
074    public static final int EXPAND = EXPN;
075    // public static final int HELP = HELP;
076    // public static final int NOOP = NOOP;
077    // public static final int TURN = TURN;
078    // public static final int QUIT = QUIT;
079    public static final int LOGOUT = QUIT;
080
081    // Cannot be instantiated
082    private SMTPCommand()
083    {}
084
085    private static final String[] _commands = {
086                                          "HELO", "MAIL FROM:", "RCPT TO:", "DATA", "SEND FROM:", "SOML FROM:",
087                                          "SAML FROM:", "RSET", "VRFY", "EXPN", "HELP", "NOOP", "TURN", "QUIT",
088                                          "AUTH", "EHLO"
089                                      };
090
091
092    static {
093        if (_commands.length != _NEXT_) {
094            throw new RuntimeException("Error in array definition");
095        }        
096    }
097
098    /***
099     * Retrieve the SMTP protocol command string corresponding to a specified
100     * command code.
101     * <p>
102     * @param command The command code.
103     * @return The SMTP protcol command string corresponding to a specified
104     *         command code.
105     ***/
106    public static final String getCommand(int command)
107    {
108        return _commands[command];
109    }
110
111}