EWS Java：使用现有项目作为附件创建新电子邮件

Question

我正在使用ews-java-api 创建一个新的电子邮件消息，其中包含现有项目作为附件。我按照 Glen 对this 问题的回答在 java 中编写了类似的代码。但是，我收到错误消息 - “不支持将 EmailMessage 类型的项目作为附件”

这是我的代码 sn-p 供参考：

EmailMessage approvalMessage = new EmailMessage(exchangeService);
ItemAttachment itemAttachment = approvalMessage.getAttachments().addItemAttachment(EmailMessage.class);

MimeContent mimeContent = ewsItem.getMimeContent();
Item attachedItem = itemAttachment.getItem();
attachedItem.setMimeContent(mimeContent);
ExtendedPropertyDefinition prFlags = new ExtendedPropertyDefinition(3591, MapiPropertyType.Integer);
attachedItem.setExtendedProperty(prFlags, "1");
itemAttachment.setName(subject);

approvalMessage.setSubject("Reminder Email with original email as attachment");
approvalMessage.getToRecipients().add("my-email-address");
approvalMessage.send();

• approvalMessage 是我正在创建的新电子邮件
• ewsItem 是我想作为附件添加到approvalMessage 的现有项目

问题：这是 ews-java-api 不接受 EmailMessage 作为附件类型的问题吗？

我尝试了什么：我用ItemAttachment itemAttachment = approvalMessage.getAttachments().addItemAttachment(Item.class);替换了ItemAttachment itemAttachment = approvalMessage.getAttachments().addItemAttachment(EmailMessage.class);

发布此更改，我不再观察到上述错误。但是，代码现在会在以下行引发 stackoverflow 错误 - attachedItem.setMimeContent(mimeContent);

错误堆栈跟踪-

Oct 09, 2018 9:02:45 PM org.apache.catalina.core.StandardWrapperValve invoke
SEVERE: Servlet.service() for servlet [dispatcher] in context with path [] 
threw exception [Handler dispatch failed; nested exception is 
java.lang.StackOverflowError] with root cause
java.lang.StackOverflowError
at microsoft.exchange.webservices.data.core.PropertyBag.changed
(PropertyBag.java:364)
at microsoft.exchange.webservices.data.property.complex.ItemAttachment.
itemChanged(ItemAttachment.java:96)
at microsoft.exchange.webservices.data.property.complex.ItemAttachment.
serviceObjectChanged(ItemAttachment.java:252)
at microsoft.exchange.webservices.data.core.service.ServiceObject.
changed(ServiceObject.java:85)
at microsoft.exchange.webservices.data.core.PropertyBag.changed
(PropertyBag.java:364)
at microsoft.exchange.webservices.data.property.complex.ItemAttachment.
itemChanged(ItemAttachment.java:96)
at microsoft.exchange.webservices.data.property.complex.ItemAttachment.
serviceObjectChanged(ItemAttachment.java:252)
at microsoft.exchange.webservices.data.core.service.ServiceObject.
changed(ServiceObject.java:85)

问题：为什么将Item指定为附件类会导致stackoverflow错误？将现有项目添加为附件的正确方法是什么？

Answer 1

StackOverflowError扩展了VirtualMachineError类，表示JVM坏了，或者资源耗尽无法操作。

更多信息，您可以参考：

java.lang.StackOverflowError – How to solve StackOverflowError

您可以添加现有项目作为附件使用下面的代码：

FolderId  folderid= new FolderId(WellKnownFolderName.Inbox,"MailboxName");    
Folder Inbox = Folder.Bind(service,folderid);  
ItemView ivItemView =  new ItemView(1) ;     
FindItemsResults<Item> fiItems = service.FindItems(Inbox.Id,ivItemView);
if(fiItems.Items.Count == 1){  
EmailMessage mail = new EmailMessage(service);   
EmailMessage OriginalEmail = (EmailMessage)fiItems.Items[0];
PropertySet  psPropset= new PropertySet(BasePropertySet.IdOnly);    
psPropset.Add(ItemSchema.MimeContent);
psPropset.Add(ItemSchema.Subject);
OriginalEmail.Load(psPropset);  
ItemAttachment Attachment = mail.Attachments.AddItemAttachment<EmailMessage>();
Attachment.Item.MimeContent = OriginalEmail.MimeContent;  
ExtendedPropertyDefinition PR_Flags = new ExtendedPropertyDefinition(3591, MapiPropertyType.Integer);    
Attachment.Item.SetExtendedProperty(PR_Flags,"1");    
Attachment.Name = OriginalEmail.Subject;  
mail.Subject = "See the Attached Email";  
mail.ToRecipients.Add("glen.scales@domain.com");
mail.SendAndSaveCopy();     

您不能直接发送另一条消息，您需要使用原始消息的 MimeContent，然后在此基础上创建一个 ItemAttachment。

参考：

Create an email using EWS Exchange and attach another email