source: org.eclipse.jetty.servlets.MultiPartFilter Multipart Form Data Filter.
This class decodes the multipart/form-data stream sent by a HTML form that uses a file input item. Any files sent are stored to a temporary file and a File object added to the request as an attribute. All other values are made available via the normal getParameter API and the setCharacterEncoding mechanism is respected when converting bytes to Strings.
If the init parameter "delete" is set to "true", any files created will be deleted when the current request returns.
The init parameter maxFormKeys sets the maximum number of keys that may be present in a form (default set by system property org.eclipse.jetty.server.Request.maxFormKeys or 1000) to protect against DOS attacks by bad hash keys.
The init parameter deleteFiles controls if uploaded files are automatically deleted after the request completes. Use init parameter "maxFileSize" to set the max size file that can be uploaded. Use init parameter "maxRequestSize" to limit the size of the multipart request.