Liem Do <liem <at> waterware.com> writes: > > Is there any way of reading MS Outlook files (.msg) I basically just want to be able to extract the To, From, > and other header fields. Can this be done with POI? Does any body have any samples of this or specific > details on which classes, methods are used to do this?
The good news is: .MSG files are OLE Doc files (also called OLE Structured Storage). So you actually can read them with the POI (POIFS -- not HSSF, which parses Excel data structures). The bad news is: POI does not contain any support for the particular structure of a .MSG file. The further bad news is: .MSG files are a different flavor of OLE Structured File than Excel. If anyone knows about OLE Structured files, they will understand this: The Mini-Stream in Excel has 64 byte blocks. The Mini-Stream in a .MSG file has 32 byte blocks. Unfortunately, POI has the mini-stream hardcoded at 64 byte blocks, and ignores the OLE Doc header where it states that the mini-stream is 32 byte blocks. You can prove the above by dumping an Excel file and looking at the first few bytes. At offset 20x you will find 06x, meaning that small data streams will use 64 byte blocks in the mini-stream. (64 = 2^6). If you dump an Outlook MSG file and look at the same byte, you will find 05x, meaning that small data streams will use 32 byte blocks in the mini-stream. (32 = 2^5). See org.apache.poi.poifs.storage.SmallDocumentBlock, which has a field private static final int _block_size = 64; This is wrong. The block size is defined in the header at byte offset 0x20 (33rd byte of the header). The further further bad news is: You want to read properties like To and From, which are stored in a truly bizarre way. Every Recipient is listed in its own storage stream. So a MSG file contains many little storage streams, each one holding information about a single property such as a recipient or sender. Since these streams are tiny, they go into the mini-stream, which POI does not parse properly. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] Mailing List: http://jakarta.apache.org/site/mail2.html#poi The Apache Jakarta Poi Project: http://jakarta.apache.org/poi/
