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.smtp; 019 020import java.text.SimpleDateFormat; 021import java.util.Date; 022import java.util.Locale; 023 024/** 025 * This class is used to construct a bare minimum acceptable header for an email message. To construct more complicated headers you should refer to RFC 5322. 026 * When the Java Mail API is finalized, you will be able to use it to compose fully compliant Internet text messages. 027 * <p> 028 * The main purpose of the class is to faciliatate the mail sending process, by relieving the programmer from having to explicitly format a simple message 029 * header. For example: 030 * 031 * <pre> 032 * writer = client.sendMessageData(); 033 * if(writer == null) // failure 034 * return false; 035 * header = 036 * new SimpleSMTPHeader("foobar@foo.com", "foo@bar.com" "Just testing"); 037 * header.addCC("bar@foo.com"); 038 * header.addHeaderField("Organization", "Foobar, Inc."); 039 * writer.write(header.toString()); 040 * writer.write("This is just a test"); 041 * writer.close(); 042 * if(!client.completePendingCommand()) // failure 043 * return false; 044 * </pre> 045 * 046 * @see SMTPClient 047 */ 048 049public class SimpleSMTPHeader { 050 private final String subject; 051 private final String from; 052 private final String to; 053 private final StringBuffer headerFields; 054 private boolean hasHeaderDate; 055 private StringBuffer cc; 056 057 /** 058 * Creates a new SimpleSMTPHeader instance initialized with the given from, to, and subject header field values. 059 * <p> 060 * 061 * @param from The value of the <code>From:</code> header field. This should be the sender's email address. Must not be null. 062 * @param to The value of the <code>To:</code> header field. This should be the recipient's email address. May be null 063 * @param subject The value of the <code>Subject:</code> header field. This should be the subject of the message. May be null 064 */ 065 public SimpleSMTPHeader(final String from, final String to, final String subject) { 066 if (from == null) { 067 throw new IllegalArgumentException("From cannot be null"); 068 } 069 this.to = to; 070 this.from = from; 071 this.subject = subject; 072 this.headerFields = new StringBuffer(); 073 this.cc = null; 074 } 075 076 /** 077 * Add an email address to the CC (carbon copy or courtesy copy) list. 078 * <p> 079 * 080 * @param address The email address to add to the CC list. 081 */ 082 public void addCC(final String address) { 083 if (cc == null) { 084 cc = new StringBuffer(); 085 } else { 086 cc.append(", "); 087 } 088 089 cc.append(address); 090 } 091 092 /** 093 * Adds an arbitrary header field with the given value to the article header. These headers will be written before the From, To, Subject, and Cc fields when 094 * the SimpleSMTPHeader is convertered to a string. An example use would be: 095 * 096 * <pre> 097 * header.addHeaderField("Organization", "Foobar, Inc."); 098 * </pre> 099 * <p> 100 * 101 * @param headerField The header field to add, not including the colon. 102 * @param value The value of the added header field. 103 */ 104 public void addHeaderField(final String headerField, final String value) { 105 if (!hasHeaderDate && "Date".equals(headerField)) { 106 hasHeaderDate = true; 107 } 108 headerFields.append(headerField); 109 headerFields.append(": "); 110 headerFields.append(value); 111 headerFields.append('\n'); 112 } 113 114 /** 115 * Converts the SimpleSMTPHeader to a properly formatted header in the form of a String, including the blank line used to separate the header from the 116 * article body. The header fields CC and Subject are only included when they are non-null. 117 * <p> 118 * 119 * @return The message header in the form of a String. 120 */ 121 @Override 122 public String toString() { 123 final StringBuilder header = new StringBuilder(); 124 125 final String pattern = "EEE, dd MMM yyyy HH:mm:ss Z"; // Fri, 21 Nov 1997 09:55:06 -0600 126 final SimpleDateFormat format = new SimpleDateFormat(pattern, Locale.ENGLISH); 127 128 if (!hasHeaderDate) { 129 addHeaderField("Date", format.format(new Date())); 130 } 131 if (headerFields.length() > 0) { 132 header.append(headerFields.toString()); 133 } 134 135 header.append("From: ").append(from).append("\n"); 136 137 if (to != null) { 138 header.append("To: ").append(to).append("\n"); 139 } 140 141 if (cc != null) { 142 header.append("Cc: ").append(cc.toString()).append("\n"); 143 } 144 145 if (subject != null) { 146 header.append("Subject: ").append(subject).append("\n"); 147 } 148 149 header.append('\n'); // end of headers; body follows 150 151 return header.toString(); 152 } 153}