grails上傳文件

def upload = { 
def f = request.getFile('myFile') 
if(!f.empty) { 
f.transferTo( new File('/some/local/dir/myfile.txt') ) 
response.sendError(200,'Done'); 
} 
else { 
flash.message = 'file cannot be empty' 
render(view:'uploadForm') 
} 
}