How to write content to a new file (overwrite if already existing) in Groovy.

write_file.groovy

//
// Write the mock request payload to a file for checking later...
// newWrite() is the important it to ensure you get a *new* file each time.
//
def filename = "C:\\MyScratchFolder\\soapUI projects\\Testing\\procon\\mock_po_activity_request.xml"
def file = new File(filename)
def w = file.newWriter() 

w << mockRequest.requestContent
w.close()

Thank you! For future readers who get here from a web search (like I did), I think it's unnecessary to use both newWriter and withWriter in the examples above. Using just withWriter will create the file if it doesn't exist yet, or replace the existing content if it already exists:

file.withWriter { w ->
  w << mockRequest.requestContent
}

Similarly, using withWriterAppend will create the file if it doesn't exist (just like above), or append to the existing content if it already exists:

file.withWriterAppend { w ->
  w << mockRequest.requestContent
}

Note that when using withWriter or withWriterAppend you can also specify a specific character encoding for the writer, and doing so is recommended as a best practice.

file.withWriter('UTF-8') { w ->
  w << mockRequest.requestContent
}