How to compose a multipart/form-data with a form field and a file

[Rice Yeh]

Hi,
  How do I compose a mulitpart/form-data with a form field and a file like
below with cxf?

        Content-type: multipart/form-data, boundary=AaB03x

        --AaB03x
        content-disposition: form-data; name="field1"

        Joe Blow
        --AaB03x
        content-disposition: form-data; name="pics"; filename="file1.txt"
        Content-Type: text/plain

         ... contents of file1.txt ...
        --AaB03x--


Regards,
Rice