这在java中是什么意思...我看到了一些新的东西，我以前从未见过这样的东西...这段代码使用spring框架javamailsender类发送邮件
public MimeMessagePreparator buildMimeMessagePreparator(final HashMap<String,Object> props) {
MimeMessagePreparator preparator = new MimeMessagePreparator() {
public void prepare(MimeMessage mimeMessage) throws Exception {
EmailTarget emailUser = (EmailTarget) props.get(EmailPropertyType.USER.getType());
EmailInfo info = (EmailInfo) props.get(EmailPropertyType.INFO.getType());
MimeMessageHelper message = new MimeMessageHelper(mimeMessage, (info.getAttachments() != null && info.getAttachments().size() > 0));
message.setTo(emailUser.getEmailAddress());
message.setFrom(info.getFromAddress());
message.setSubject(info.getSubject());
if (emailUser.getBCCAddresses() != null && emailUser.getBCCAddresses().length > 0) {
message.setBcc(emailUser.getBCCAddresses());
}
if (emailUser.getCCAddresses() != null && emailUser.getCCAddresses().length > 0) {
message.setCc(emailUser.getCCAddresses());
}
String messageBody = info.getMessageBody();
if (messageBody == null) {
messageBody = buildMessageBody(info, props);
}
message.setText(messageBody, true);
for (Attachment attachment : info.getAttachments()) {
ByteArrayDataSource dataSource = new ByteArrayDataSource(attachment.getData(), attachment.getMimeType());
message.addAttachment(attachment.getFilename(), dataSource);
}
}
}; // why there is a semicolon here
return preparator;
}