Roger,
Having written internal library code for both javac and jtreg to do what
you suggest, I would support such an API.
I note that as well as parsing system properties, it would also be a
useful API for command-line tools that accept paths as options.
However, I would suggest that it is more appropriate to return a
List<Path> than a List<String>. It is better to bias the API towards an
appropriate type (i.e. Path) than to leave it to the user to create a
stream to do the conversion. Those folk that still want a File can
still create the stream to do the conversion if they so desire.
By converting to Paths as part of the API, it becomes a clearer point to
specify and document the possibility of InvalidPathException.
-- Jon
On 7/19/18 12:39 PM, Roger Riggs wrote:
Hi,
Parsing of paths such as the values of properties java.class.path and
java.library.path
do not have direct support in the Java API.
There are several implementations within OpenJDK and a few variations
exist with regard to
treatment of empty path elements and on Windows support for quoting.
Would it be useful to have an API such as the following:
/**
* Returns a list of paths parsed from a string separated by
{@link File#pathSeparator}.
* All characters except the {@link File#pathSeparator} are allowed.
* Some operating systems support quoting segments of the string
* potentially including {@code pathSeparator} characters.
* Empty paths, identified by leading, trailing, and adjacent
separator characters,
* can be omitted or replaced with a non-null provided path.
*
* @implNote
* On Windows, zero or more characters between double-quotes
({@code "}) are included
* literally in the path, regardless of whether they are valid in
a path.
*
* @param path a string containing paths separated by the {@link
File#pathSeparator}
* @param emptyPath a path to replace an empty path or {@code
null} to ignore empty paths
* @return an immutable list of strings for each path; {@code
non-null}
*/
public static List<String> parsePathStrings(String path, String
emptyPath) { ...}
There are of course, possible variations and convenience versions but
the API should be kept to the essentials.
With java.util.streams it becomes easy to process each component or to
map the strings to Files or Path.
Suggestions welcome, Roger
