Since we're going to allow our users to upload/store images, we need to validate the files they send us. Doing some research on the web, it appears we need to check the following:
1) The actual image binary data. Is the file a valid image? Is it a web image type (E.g. jpeg, gif, png)
2) The image does not have extreme dimensions. No 1x20000 images should be allowed
3) The filename extensions should match the image data. We can correct this automatically if we can identify the image type.
4) The image size should also be capped. The Struts Upload is already capping file upload sizes for us. However, we might want to cap images even lower. Have to talk to marketing about that...
The javax.imageio package seems to have all the tools I need for this.