1.設置系統值
System.setProperty("mail.mime.splitlongparameters", "false");
2. 這里,在創建對象的時候定義編碼格式(utf-8):
MimeMessageHelper helper = new MimeMessageHelper(mes, true, "utf-8");
3. 其次,在添加附件的時候,附件名是需要定義編碼的
helper.addAttachment(MimeUtility.encodeWord(附件名,"utf-8","B"), 你的附件對象);
