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 * http://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 import java.util.Enumeration;
21 import java.util.Vector;
22
23 /***
24 * A class used to represent forward and reverse relay paths. The
25 * SMTP MAIL command requires a reverse relay path while the SMTP RCPT
26 * command requires a forward relay path. See RFC 821 for more details.
27 * In general, you will not have to deal with relay paths.
28 * <p>
29 * <p>
30 * @author Daniel F. Savarese
31 * @see SMTPClient
32 ***/
33
34 public final class RelayPath
35 {
36 Vector<String> _path;
37 String _emailAddress;
38
39 /***
40 * Create a relay path with the specified email address as the ultimate
41 * destination.
42 * <p>
43 * @param emailAddress The destination email address.
44 ***/
45 public RelayPath(String emailAddress)
46 {
47 _path = new Vector<String>();
48 _emailAddress = emailAddress;
49 }
50
51 /***
52 * Add a mail relay host to the relay path. Hosts are added left to
53 * right. For example, the following will create the path
54 * <code><b> < @bar.com,@foo.com:foobar@foo.com > </b></code>
55 * <pre>
56 * path = new RelayPath("foobar@foo.com");
57 * path.addRelay("bar.com");
58 * path.addRelay("foo.com");
59 * </pre>
60 * <p>
61 * @param hostname The host to add to the relay path.
62 ***/
63 public void addRelay(String hostname)
64 {
65 _path.addElement(hostname);
66 }
67
68 /***
69 * Return the properly formatted string representation of the relay path.
70 * <p>
71 * @return The properly formatted string representation of the relay path.
72 ***/
73 @Override
74 public String toString()
75 {
76 StringBuffer buffer = new StringBuffer();
77 Enumeration<String> hosts;
78
79 buffer.append('<');
80
81 hosts = _path.elements();
82
83 if (hosts.hasMoreElements())
84 {
85 buffer.append('@');
86 buffer.append(hosts.nextElement());
87
88 while (hosts.hasMoreElements())
89 {
90 buffer.append(",@");
91 buffer.append(hosts.nextElement());
92 }
93 buffer.append(':');
94 }
95
96 buffer.append(_emailAddress);
97 buffer.append('>');
98
99 return buffer.toString();
100 }
101
102 }