How to use Embedded Equations in Java Apache POI library?

I am trying to use "Apache POI" to extract embedded equation and text from a .doc MS Word file into a .ppt MS Powerpoint file, I have successfully extracted text, but how do I extract embedded开发者_JS百科 equations?

the Embedded Equations comes out like this if I only extract it as text:

!!EMBED Equation.3

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This may not help you with the binary .doc format, but for the newer .docx format, I was able to get to the equation, which is embedded as an OLE document, using the following code:

 InputStream in = new FileInputStream(f);
 XWPFDocument doc = new XWPFDocument(in);
 for (PackagePart p : doc.getAllEmbedds()) {
   POIFSFileSystem poifs = new POIFSFileSystem(p.getInputStream());
   byte[] oleData = IOUtils.toByteArray(
              poifs.createDocumentInputStream("Equation Native"));
 }

And then you can extract the MathType data in there and hand it to a MTEF parser.

If you don't need the MathType data, there is also a placeholder image (in WMF format) that just renders the equation.