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
018 package org.apache.commons.net.smtp;
019
020 import java.util.Enumeration;
021 import java.util.Vector;
022
023 /***
024 * A class used to represent forward and reverse relay paths. The
025 * SMTP MAIL command requires a reverse relay path while the SMTP RCPT
026 * command requires a forward relay path. See RFC 821 for more details.
027 * In general, you will not have to deal with relay paths.
028 * <p>
029 * <p>
030 * @author Daniel F. Savarese
031 * @see SMTPClient
032 ***/
033
034 public final class RelayPath
035 {
036 Vector<String> _path;
037 String _emailAddress;
038
039 /***
040 * Create a relay path with the specified email address as the ultimate
041 * destination.
042 * <p>
043 * @param emailAddress The destination email address.
044 ***/
045 public RelayPath(String emailAddress)
046 {
047 _path = new Vector<String>();
048 _emailAddress = emailAddress;
049 }
050
051 /***
052 * Add a mail relay host to the relay path. Hosts are added left to
053 * right. For example, the following will create the path
054 * <code><b> < @bar.com,@foo.com:foobar@foo.com > </b></code>
055 * <pre>
056 * path = new RelayPath("foobar@foo.com");
057 * path.addRelay("bar.com");
058 * path.addRelay("foo.com");
059 * </pre>
060 * <p>
061 * @param hostname The host to add to the relay path.
062 ***/
063 public void addRelay(String hostname)
064 {
065 _path.addElement(hostname);
066 }
067
068 /***
069 * Return the properly formatted string representation of the relay path.
070 * <p>
071 * @return The properly formatted string representation of the relay path.
072 ***/
073 @Override
074 public String toString()
075 {
076 StringBuffer buffer = new StringBuffer();
077 Enumeration<String> hosts;
078
079 buffer.append('<');
080
081 hosts = _path.elements();
082
083 if (hosts.hasMoreElements())
084 {
085 buffer.append('@');
086 buffer.append(hosts.nextElement());
087
088 while (hosts.hasMoreElements())
089 {
090 buffer.append(",@");
091 buffer.append(hosts.nextElement());
092 }
093 buffer.append(':');
094 }
095
096 buffer.append(_emailAddress);
097 buffer.append('>');
098
099 return buffer.toString();
100 }
101
102 }