1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * https://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17
18 package org.apache.commons.net.smtp;
19
20 /**
21 * SMTPCommand stores a set of constants for SMTP command codes. To interpret the meaning of the codes, familiarity with RFC 821 is assumed. The mnemonic
22 * constant names are transcriptions from the code descriptions of RFC 821. For those who think in terms of the actual SMTP commands, a set of constants such as
23 * {@link #HELO HELO} are provided where the constant name is the same as the SMTP command.
24 */
25 public final class SMTPCommand {
26
27 /** SMTP command {@value}. */
28 public static final int HELO = 0;
29
30 /** SMTP command {@value}. */
31 public static final int MAIL = 1;
32
33 /** SMTP command {@value}. */
34 public static final int RCPT = 2;
35
36 /** SMTP command {@value}. */
37 public static final int DATA = 3;
38
39 /** SMTP command {@value}. */
40 public static final int SEND = 4;
41
42 /** SMTP command {@value}. */
43 public static final int SOML = 5;
44
45 /** SMTP command {@value}. */
46 public static final int SAML = 6;
47
48 /** SMTP command {@value}. */
49 public static final int RSET = 7;
50
51 /** SMTP command {@value}. */
52 public static final int VRFY = 8;
53
54 /** SMTP command {@value}. */
55 public static final int EXPN = 9;
56
57 /** SMTP command {@value}. */
58 public static final int HELP = 10;
59
60 /** SMTP command {@value}. */
61 public static final int NOOP = 11;
62
63 /** SMTP command {@value}. */
64 public static final int TURN = 12;
65
66 /** SMTP command {@value}. */
67 public static final int QUIT = 13;
68
69 /**
70 * The authorization command
71 *
72 * @since 3.0
73 */
74 public static final int AUTH = 14;
75
76 /**
77 * The extended hello command
78 *
79 * @since 3.0
80 */
81 public static final int EHLO = 15;
82
83 private static final int NEXT = EHLO + 1; // update as necessary when adding new entries
84
85 /** Alias for {@value}. */
86 public static final int HELLO = HELO;
87
88 /** Alias for {@value}. */
89 public static final int LOGIN = HELO;
90
91 /** Alias for {@value}. */
92 public static final int MAIL_FROM = MAIL;
93
94 /** Alias for {@value}. */
95 public static final int RECIPIENT = RCPT;
96
97 /** Alias for {@value}. */
98 public static final int SEND_MESSAGE_DATA = DATA;
99
100 /** Alias for {@value}. */
101 public static final int SEND_FROM = SEND;
102
103 /** Alias for {@value}. */
104 public static final int SEND_OR_MAIL_FROM = SOML;
105
106 /** Alias for {@value}. */
107 public static final int SEND_AND_MAIL_FROM = SAML;
108
109 /** Alias for {@value}. */
110 public static final int RESET = RSET;
111
112 /** Alias for {@value}. */
113 public static final int VERIFY = VRFY;
114
115 /** Alias for {@value}. */
116 public static final int EXPAND = EXPN;
117
118 /** Alias for {@value}. */
119 public static final int LOGOUT = QUIT;
120
121 private static final String[] commands = { "HELO", "MAIL FROM:", "RCPT TO:", "DATA", "SEND FROM:", "SOML FROM:", "SAML FROM:", "RSET", "VRFY", "EXPN",
122 "HELP", "NOOP", "TURN", "QUIT", "AUTH", "EHLO" };
123
124 static {
125 if (commands.length != NEXT) {
126 throw new IllegalStateException("Error in array definition");
127 }
128 }
129
130 /**
131 * Gets the SMTP protocol command string corresponding to a specified command code.
132 *
133 * @param command The command code.
134 * @return The SMTP protocol command string corresponding to a specified command code.
135 */
136 public static String getCommand(final int command) {
137 return commands[command];
138 }
139
140 /** Cannot be instantiated. */
141 private SMTPCommand() {
142 }
143
144 }