1 /*
2 * Copyright 2016 The Netty Project
3 *
4 * The Netty Project licenses this file to you under the Apache License,
5 * version 2.0 (the "License"); you may not use this file except in compliance
6 * with the License. You may obtain a copy of the License at:
7 *
8 * https://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
12 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
13 * License for the specific language governing permissions and limitations
14 * under the License.
15 */
16 package io.netty.handler.codec.smtp;
17
18 import io.netty.buffer.ByteBuf;
19 import io.netty.buffer.Unpooled;
20 import io.netty.util.internal.UnstableApi;
21
22 /**
23 * The last part of a sequence of {@link SmtpContent}s that are sent after a {@code DATA} request.
24 * Be aware that a {@link SmtpContent} / {@link LastSmtpContent} sequence must always use CRLF as line delimiter
25 * and the lines that start with a DOT must be escaped with an extra DOT as
26 * specified by <a href="https://www.ietf.org/rfc/rfc2821.txt">RFC2821</a>.
27 */
28 @UnstableApi
29 public interface LastSmtpContent extends SmtpContent {
30
31 /**
32 * Empty {@link LastSmtpContent}.
33 */
34 LastSmtpContent EMPTY_LAST_CONTENT = new LastSmtpContent() {
35 @Override
36 public LastSmtpContent copy() {
37 return this;
38 }
39
40 @Override
41 public LastSmtpContent duplicate() {
42 return this;
43 }
44
45 @Override
46 public LastSmtpContent retainedDuplicate() {
47 return this;
48 }
49
50 @Override
51 public LastSmtpContent replace(ByteBuf content) {
52 return new DefaultLastSmtpContent(content);
53 }
54
55 @Override
56 public LastSmtpContent retain() {
57 return this;
58 }
59
60 @Override
61 public LastSmtpContent retain(int increment) {
62 return this;
63 }
64
65 @Override
66 public LastSmtpContent touch() {
67 return this;
68 }
69
70 @Override
71 public LastSmtpContent touch(Object hint) {
72 return this;
73 }
74
75 @Override
76 public ByteBuf content() {
77 return Unpooled.EMPTY_BUFFER;
78 }
79
80 @Override
81 public int refCnt() {
82 return 1;
83 }
84
85 @Override
86 public boolean release() {
87 return false;
88 }
89
90 @Override
91 public boolean release(int decrement) {
92 return false;
93 }
94 };
95
96 @Override
97 LastSmtpContent copy();
98
99 @Override
100 LastSmtpContent duplicate();
101
102 @Override
103 LastSmtpContent retainedDuplicate();
104
105 @Override
106 LastSmtpContent replace(ByteBuf content);
107
108 @Override
109 LastSmtpContent retain();
110
111 @Override
112 LastSmtpContent retain(int increment);
113
114 @Override
115 LastSmtpContent touch();
116
117 @Override
118 LastSmtpContent touch(Object hint);
119 }