How do implement EntityResolver for XSLT XML transformation

[ajay bhadauria]

Hi,
 
I am using transform method to transform input xml source to output xml. In the 
xslt, I have document () call to resolve external entities. The external enties 
are available in memory instead of file-system files during transformation.
 
Please help me how do I write my own entity resolver to resolve external enties 
during xml transformation . Any code example referenece will be great.
 
Thanks
Ajay