Retain Google Apps

Level 2

The Google Apps job is multithreaded, with 6 folder threads and 2 message threads per folder thread. JavaMail, which is the code on which this is built, only supports 1 thread per message download, so once thread 1 has completed its download and begins transferring the message to the Server, thread 2 begins a download.

While an attachment is being downloaded, it is cached in temporary directory: /var/cache/retain-tomcat7/temp/stream. The job creates a subdirectory under that path where it stores the temp file. Once the attachment is processed, the temp file is deleted.