Pathを任意のセパレータを用いて文字列化する。JavaとStreamによる方法。

pathToStringWithSeparator.groovy

import java.nio.file.Path
import java.nio.file.Paths
 
def p = Paths.get('aaa', 'bbb', 'ccc').resolve('xxx/yyy/zzz/')
assert p as String == /aaa\bbb\ccc\xxx\yyy\zzz/

import java.util.stream.*
def pathToString(Path path, String separator = '/', boolean startsWithSeparator = false) {
    StreamSupport.stream(path.spliterator(), false)
       .map{ it.toString() }
       .collect(Collectors.joining(separator, (startsWithSeparator ? separator : ''), ''))
}
assert pathToString(p, '/', true)  == '/aaa/bbb/ccc/xxx/yyy/zzz'
assert pathToString(p, '/', false) ==  'aaa/bbb/ccc/xxx/yyy/zzz'
assert pathToString(p, '::', false) ==  'aaa::bbb::ccc::xxx::yyy::zzz'