有时候,我们需要把从数据库中查出来的资料,动态生成eml文件进行保存和发送,有的还需要嵌入附件,用什么方法来生成eml文件 ?如何本地生成邮件eml文件。
参考了JAVAMAIL通过IMAP协议保存的eml文件格式后,我们自己也可以本地构造eml文件。
还是看例子吧。
String mailbody = ""; mailbody = "Message-ID:"+uid+"\r\n"; mailbody = mailbody+"X-FreePOPs-User: "+user+"\r\n"; mailbody = mailbody+"X-FreePOPs-Domain: "+domain+"\r\n"; mailbody = mailbody+"Subject: "+sub+"\r\n"; mailbody = mailbody+"Date: "+sentDate+" \r\n"; mailbody = mailbody+"From: "+from+"\r\n"; mailbody = mailbody+"To: "+to+"\r\n" ; mailbody = mailbody+"MIME-Version: 1.0\r\n";
BASE64Encoder encoder = new BASE64Encoder();
byte[] data = "body".getBytes(); try{ MessageDigest digest = MessageDigest.getInstance("MD5"); digest.update(((new Random()).nextInt() + "").getBytes()); data = digest.digest();// Get a romdom integer and get it's digest }catch (Exception e) { e.printStackTrace(); } String mainBoundary = "****MAIN_BOUNDARY****" + byte2hex(data); // Main boundary String subBoundary = "****SUB_BOUNDARY****" + byte2hex(data); mailbody += "Content-Type: multipart/mixed;\r\n" + "\tboundary=\"" + mainBoundary + "\"\r\n" + "\r\n" + "This is a multi-part message in MIME format.\r\n" + "\r\n" // Above is mail's header + "--" + mainBoundary + "\r\n" // The mail's text body + "Content-Type: multipart/alternative;\r\n" + "\tboundary=\"" + subBoundary + "\"\r\n" + "\r\n" + "--" + subBoundary + "\r\n"; mailbody += "Content-Type: text/html;\r\n"; mailbody += "\tcharset=\"utf-8\"\r\n" + "Content-Transfer-Encoding: 7bit\r\n" + "\r\n" + massage + "\r\n" + "\r\n" + "--" + subBoundary + "--\r\n"// End of sub boundary + "\r\n"; // for (int i = 0; i < fjs.size(); i++) { List<Object> attachment = fjs.get(i); String attachName = (String)attachment.get(0); Matcher m = Pattern.compile("[\\u4e00-\\u9fa5]").matcher(attachName); try{ if(m.find()){ attachName = MimeUtility.encodeText(attachName, "gb18030", "B"); }else{ attachName = MimeUtility.encodeText(attachName, "utf-8", "B"); } }catch (Exception e) { attachName = "attachName_"+i; e.printStackTrace(); } try{ mailbody += "--" + mainBoundary + "\r\n" + "Content-Type:" + (String)attachment.get(1) + ";\r\n" + "\tname=\"" + attachName + "\"\r\n" + "Content-Transfer-Encoding: base64\r\n" + "Content-Disposition: attachment;\r\n" + "\tfilename=\"" + attachName + "\"\r\n" + "\r\n" + encoder.encode((byte[])attachment.get(2)) + "\r\n" + "\r\n"; }catch (Exception e) { e.printStackTrace(); } } mailbody += "--" + mainBoundary + "--";
BufferedWriter bw = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(fullFileName), "UTF-8"));
bw.write(mailbody);
bw.flush(); bw.close();
其后可以用foxmail等工具打开eml来查看附件是否可以下载,eml内容是否可以解析。