如何使用 JavaMail 获取邮件帐户中可用文件夹的列表

Here is the code that works. This will give you handle to all the Labels. To go deeper in a folder, you may perform folder.list() or you can use store.getDefaultFolder().list("*") to retrieve all the folders and sub-folders as suggested in the other answer.

Properties props = System.getProperties();
props.setProperty("mail.store.protocol", "imaps");
Session session = Session.getDefaultInstance(props, null);
Store store = session.getStore("imaps");
store.connect("imap.gmail.com", "YOURMAILID@gmail.com", "UR_P@ZZWRD");
System.out.println(store);

Folder[] f = store.getDefaultFolder().list();
for(Folder fd:f)
    System.out.println(">> "+fd.getName());

输出:

>>收件箱
>>个人
>>收据
>>旅游
>>工作
>>[邮箱]