    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.pop3;
    019
    020/**
    021 * POP3Command stores POP3 command code constants.
    022 *
    023 *
    024 */
    025
    026public final class POP3Command
    027{
    028    /** Send user name. */
    029    public static final int USER = 0;
    030    /** Send password. */
    031    public static final int PASS = 1;
    032    /** Quit session. */
    033    public static final int QUIT = 2;
    034    /** Get status. */
    035    public static final int STAT = 3;
    036    /** List message(s). */
    037    public static final int LIST = 4;
    038    /** Retrieve message(s). */
    039    public static final int RETR = 5;
    040    /** Delete message(s). */
    041    public static final int DELE = 6;
    042    /** No operation.  Used as a session keepalive. */
    043    public static final int NOOP = 7;
    044    /** Reset session. */
    045    public static final int RSET = 8;
    046    /** Authorization. */
    047    public static final int APOP = 9;
    048    /** Retrieve top number lines from message. */
    049    public static final int TOP = 10;
    050    /** List unique message identifier(s). */
    051    public static final int UIDL = 11;
    052    /**
    053     * The capabilities command.
    054     * @since 3.0
    055     */
    056    public static final int CAPA = 12;
    057    /**
    058     * Authentication
    059     * @since 3.0
    060     */
    061    public static final int AUTH = 13;
    062
    063    private static final int NEXT = AUTH + 1; // update as necessary when adding new entries
    064
    065    static final String[] commands = {
    066                                          "USER", "PASS", "QUIT", "STAT", "LIST", "RETR", "DELE", "NOOP", "RSET",
    067                                          "APOP", "TOP", "UIDL", "CAPA", "AUTH",
    068                                      };
    069
    070    static {
    071        if (commands.length != NEXT) {
    072            throw new RuntimeException("Error in array definition");
    073        }
    074    }
    075
    076    // Cannot be instantiated.
    077    private POP3Command()
    078    {}
    079
    080    /**
    081     * Get the POP3 protocol string command corresponding to a command code.
    082     * @param command the command code
    083     *
    084     * @return The POP3 protocol string command corresponding to a command code.
    085     */
    086    public static String getCommand(final int command)
    087    {
    088        return commands[command];
    089    }
    090}