使用.net和java两种方式收取Gmail邮件。

╰半橙微兮° 2022-09-17 15:23 234阅读 0赞

公司最近安排做收取用户邮件的模块，主要针对一些知名的大牌信箱。首先考虑Gmail，它有2G的容量、Web2.0的框架，是当然不让的首选。

GMail有一个特点，它不直接提供POP3的接口。不过有一个XML的Feeds地址，需要登陆才能查看。地址如下：  
[https://mail.google.com/mail/feed/atom][https_mail.google.com_mail_feed_atom]

登陆进去后，XML格式是这样的：

![None.gif][]   
![None.gif][] <? xml version="1.0" encoding="UTF-8"  ?>   
![None.gif][] < feed  version ="0.3"  xmlns ="http://purl.org/atom/ns\#" >   
![None.gif][] < title > Gmail - Inbox for li.jadesun@gmail.com </ title >   
![None.gif][] < tagline > New messages in your Gmail Inbox </ tagline >   
![None.gif][] < fullcount > 1 </ fullcount >   
![None.gif][] < link  rel ="alternate"  href ="http://mail.google.com/mail"  type ="text/html"  />   
![None.gif][] < modified > 2006-10-24T15:31:48Z </ modified >   
![None.gif][] < entry >   
![None.gif][] < title > 欢迎光临Yahoo! - 请激活您的帐户 </ title >   
![None.gif][] < summary > width=1 帐户信息 帮助 不要回复此封邮件。如果您没有创建一个帐户，请  &hellip; </ summary >   
![None.gif][] < link  rel ="alternate"  href ="http://mail.google.com/mail?xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"  type ="text/html"  />   
![None.gif][] < modified > 2006-10-24T09:34:37Z </ modified >   
![None.gif][] < issued > 2006-10-24T09:34:37Z </ issued >   
![None.gif][] < id > tag:gmail.google.com,2004:1218112365137369397 </ id >   
![None.gif][] < author >   
![None.gif][] < name > my-yahoo-register </ name >   
![None.gif][] < email > my-yahoo-register@yahoo-inc.com </ email >   
![None.gif][] </ author >   
![None.gif][] </ entry >   
![None.gif][] </ feed >

研究了一天，用.net实现了登陆收取的方法，采用WebRequest对象来实现的。

![None.gif][] wrGETURL  =   
![None.gif][] WebRequest.Create( " https://mail.google.com/mail/feed/atom " );  
![None.gif][]  
![None.gif][] if (clsMain.g\_UseProxy)  
![ExpandedBlockStart.gif][]![ContractedBlock.gif][] ... \{  
![InBlock.gif][] wrGETURL.Proxy = clsMain.GetProxy();  
![ExpandedBlockEnd.gif][]\}   
![None.gif][]  
![None.gif][]bytes  =  Encoding.ASCII.GetBytes(txtUserName.Text.Trim()  \+  " : "   
![None.gif][] \+  txtUserPassword.Text.Trim());  
![None.gif][]  
![None.gif][]wrGETURL.Headers.Add( " Authorization " ,  
![None.gif][] " Basic  "  \+  Convert.ToBase64String(bytes));  
![None.gif][]  
![None.gif][]  
![None.gif][]  
![None.gif][]Stream feedStream  =   
![None.gif][] wrGETURL.GetResponse().GetResponseStream();  
![None.gif][]  
![None.gif][]Atom.Core.AtomFeed myFeed;  
![None.gif][]  
![None.gif][]myFeed  =  Atom.Core.AtomFeed.Load(feedStream);  
![None.gif][]  
![None.gif][] //  Get the date and time of the feed.   
![None.gif][] strFeedTime  =  myFeed.Modified.DateTime.Day.ToString()  \+  " \- "   
![None.gif][] \+  myFeed.Modified.DateTime.ToString( " MMM " )  \+  " \- "   
![None.gif][] \+  myFeed.Modified.DateTime.Year.ToString()  \+  "  "   
![None.gif][] \+  myFeed.Modified.DateTime.TimeOfDay.ToString();  
![None.gif][]  
![None.gif][]feedTime =  DateTime.Parse(strFeedTime);  
![None.gif][]  
![None.gif][]Atom.Core.Collections.AtomEntryCollection ents  =   
![None.gif][] myFeed.Entries;  
![None.gif][]  
![None.gif][] foreach (Atom.Core.AtomEntry ent  in  ents)  
![ExpandedBlockStart.gif][]![ContractedBlock.gif][] ... \{ ...\{  
![InBlock.gif][] FromName = ent.Author.Name;  
![InBlock.gif][] Title = ent.Title.Content;  
![InBlock.gif][] Content = ent.Summary.Content;  
![InBlock.gif][]//Do something else  
![ExpandedSubBlockEnd.gif][]\}  
![InBlock.gif][]

这里用到了一个开源的组件支持(Atom)，把Stream流数据转成了XML数据，并进行了解析，可以在[http://atomnet.sourceforge.net/][http_atomnet.sourceforge.net]下载得到。

该代码经同事帮忙，改写在JAVA下面了，终于能在项目中应用，我顺便把JAVA代码贴出来，写在Action中的。

![None.gif][] import  java.net.URL;  
![None.gif][] import  java.net.URLConnection;  
![None.gif][]  
![None.gif][] import  javax.servlet.http.HttpServletRequest;  
![None.gif][] import  javax.servlet.http.HttpServletResponse;  
![None.gif][]  
![None.gif][] import  org.apache.struts.action.Action;  
![None.gif][] import  org.apache.struts.action.ActionForm;  
![None.gif][] import  org.apache.struts.action.ActionForward;  
![None.gif][] import  org.apache.struts.action.ActionMapping;  
![None.gif][]  
![None.gif][] import  sun.misc.BASE64Encoder;  
![None.gif][]  
![ExpandedBlockStart.gif][]![ContractedBlock.gif][] public  class  GmailAction  extends  Action ... \{  
![InBlock.gif][]  
![ExpandedSubBlockStart.gif][]![ContractedSubBlock.gif][]/\*\* \*//\*\*  
![InBlock.gif][] \* Gmail feed get  
![ExpandedSubBlockEnd.gif][]\*/  
![InBlock.gif][]  
![InBlock.gif][] @Override  
![InBlock.gif][]public ActionForward execute(ActionMapping mapping,ActionForm form,  
![ExpandedSubBlockStart.gif][]![ContractedSubBlock.gif][] HttpServletRequest request,HttpServletResponse response) throws Exception ...\{  
![InBlock.gif][]  
![InBlock.gif][]  
![InBlock.gif][] String username =request.getParameter("username");  
![InBlock.gif][] String password =request.getParameter("password");  
![InBlock.gif][] URL server =new URL("https://mail.google.com/mail/feed/atom");  
![InBlock.gif][] URLConnection connection = server.openConnection();  
![InBlock.gif][] PasswordAuthentication pa = Authenticator.requestPasswordAuthentication(  
![InBlock.gif][] InetAddress.getByName(connection.getURL().getHost()),  
![InBlock.gif][] connection.getURL().getPort(),  
![InBlock.gif][] connection.getURL().getProtocol(),  
![InBlock.gif][]null,  
![InBlock.gif][]"Basic");  
![InBlock.gif][] StringBuffer buf =new StringBuffer(username);  
![InBlock.gif][] buf.append(":");  
![InBlock.gif][] buf.append(password);  
![InBlock.gif][] String encoded =new BASE64Encoder().encode(buf.toString().getBytes());;  
![InBlock.gif][] connection.setRequestProperty ("Authorization", "Basic "\+ encoded);  
![InBlock.gif][] connection.connect();  
![InBlock.gif][] InputStream in = connection.getInputStream();  
![InBlock.gif][]  
![InBlock.gif][]byte \[\] data =newbyte \[1<<10\];  
![InBlock.gif][] ByteArrayOutputStream baos =new ByteArrayOutputStream();  
![InBlock.gif][]for(int i; (i=in.read(data))!=-1; baos.write(data,0,i));  
![InBlock.gif][]byte \[\] badata = baos.toByteArray();  
![InBlock.gif][] response.getOutputStream().write(badata);  
![InBlock.gif][]returnnull;  
![ExpandedSubBlockEnd.gif][] \}  
![InBlock.gif][]  
![InBlock.gif][]  
![InBlock.gif][]  
![ExpandedBlockEnd.gif][]\}

response.getOutputStream().write(badata); 输出的就是XML数据，拿着用就是了。解决了收取GMail邮件的问题。

[https_mail.google.com_mail_feed_atom]: https://mail.google.com/mail/feed/atom
[None.gif]: /images/20220828/bc97e78900384187bb6238f012c51481.png
[ExpandedBlockStart.gif]: http://images.csdn.net/syntaxhighlighting/OutliningIndicators/ExpandedBlockStart.gif
[ContractedBlock.gif]: /images/20220828/f7afb7ec45db43b5b696b4780b890113.png
[InBlock.gif]: /images/20220828/e5dc0c8b25ff4f40bced4bc6f51dcd6a.png
[ExpandedBlockEnd.gif]: /images/20220828/6e7f11eb48dd499fb28b2ae295c5beed.png
[ExpandedSubBlockEnd.gif]: /images/20220828/361eaf66a7d643dba7fd858c92455fc8.png
[http_atomnet.sourceforge.net]: http://atomnet.sourceforge.net/
[ExpandedSubBlockStart.gif]: http://images.csdn.net/syntaxhighlighting/OutliningIndicators/ExpandedSubBlockStart.gif
[ContractedSubBlock.gif]: /images/20220828/d203a398ff404f88804e92f45a1a9f4d.png