我正在阅读Office 365 Mail帐户的收件箱并下载它的附件(txt文件)。它适用于小于2 MB的小文件,但当我尝试使用20 MB文件时,它确实很慢。我在两台不同的机器(Linux和Windows)上测试代码,速度相同,速度非常慢。Java Mail慢速下载附件Office 365
String user = "[email protected]";
String password = "mypassword";
try{
boolean foundSites = false;
// Get a Properties object
Properties properties = new Properties();
properties.put("mail.imaps.host", host);
properties.put("mail.imaps.port", port);
properties.put("mail.imaps.starttls.enable", SSL);
//properties.put("mail.imap.fetchsize", "1000000");
Session emailSession = Session.getDefaultInstance(properties);
//create the POP3 store object and connect with the pop server
Store store = emailSession.getStore("imaps");
store.connect(host, user, password);
//create the folder object and open it
Folder emailFolder = store.getFolder("INBOX");
emailFolder.open(Folder.READ_ONLY);
// retrieve the messages from the folder in an array and print it
Message[] messages = emailFolder.getMessages();
System.out.println("messages.length---" + messages.length);
LocalDateTime now = LocalDateTime.now();
int year = now.getYear();
int month = now.getMonthValue();
int day = now.getDayOfMonth();
for (int i = messages.length - 1; i >= 0; i--) {
Message message = messages[i];
Calendar cal = Calendar.getInstance();
cal.setTime(message.getReceivedDate());
int yearMessage = cal.get(Calendar.YEAR);
int monthMessage = cal.get(Calendar.MONTH) + 1;
int dayMessage = cal.get(Calendar.DAY_OF_MONTH);
if(year == yearMessage && month == monthMessage && day == dayMessage)
{
//The real code is doing this with 20 Subjects (20 emails)
if(message.getSubject().equalsIgnoreCase("Integration - Site Info") && foundSites != true)
{
System.out.println("found Integration - Site Info");
Multipart multipart = (Multipart) message.getContent();
List<File> attachments = new ArrayList<>();
for (int j = 0; j < multipart.getCount(); j++) {
BodyPart bodyPart = multipart.getBodyPart(j);
if(Part.ATTACHMENT.equalsIgnoreCase(bodyPart.getDisposition()))
{
InputStream is = bodyPart.getInputStream();
File f = new File("./attachments/"
+ "sites_"+Integer.toString(day)+"-"+Integer.toString(month)+"-"+Integer.toString(year)+".csv");
FileOutputStream fos = new FileOutputStream(f);
byte[] buf = new byte[4096];
int bytesRead;
while((bytesRead = is.read(buf))!=-1) {
fos.write(buf, 0, bytesRead);
}
fos.close();
attachments.add(f);
foundSites = true;
break;
}
}
}
}
if(foundSites)
{
break;
}
} catch (Exception e) {
System.out.println(e);
}
我可以创建线程,但有没有其他的选择?
只是旁注: 我用python试试代码,速度显着提高。
====================================== UPDATE 1:
我做了saveFile方法的改变,代码简化了很多,但仍然有相同的下载速度,每秒10 KB。
MimeBodyPart bodyPart = (MimeBodyPart) multipart.getBodyPart(j);
if(Part.ATTACHMENT.equalsIgnoreCase(bodyPart.getDisposition()))
{
bodyPart.saveFile("./attachments/"
+ "sites_"+Integer.toString(day)+"-"+Integer.toString(month)+"-"+Integer.toString(year)+".csv");
速度真的很慢吗?速度有多快? – shmosel
你是否分析了代码?用jvisualvm运行它,并告诉我们哪个部分很慢。关闭我的头顶,你*可能*添加缓冲到'FileOutputStream'。 –