How to separate List elements with commas in Groovy?

def names =开发者_C百科 ["myname", "yourname", "theirname", "allnames"]

String n = ""
names.each{
    n += it + ","
}

println n

Output:

myname,yourname,theirname,allnames,

How do I get rid of the trailing comma?

names.join(",")