The NIO api can be very annoying. Hover I think here the problem is that Paths.get(<string path>) is designed to only return default file (local) system path objects.
Instead Paths.get(<URI>) allows the automatic creation of a new file system as stated by the documentation <https://docs.oracle.com/javase/7/docs/api/java/nio/file/Paths.html#get(java.net.URI)> . *Throws * *FileSystemNotFoundException - The file system, identified by the URI, does not exist and cannot be created *automatically*, or the provider identified by the URI's scheme component is not installed* However is role of FileSystemProvider implementation to automatically create a new file system if does not exist and, I think, the ZipFileSystemProvider is not doing that. p On Thu, May 31, 2018 at 8:53 AM, Schalk Cronjé <ysb...@gmail.com> wrote: > HI all, > > Java NIO2 providers (https://docs.oracle.com/javase/8/docs/api/java/nio/ > file/spi/FileSystemProvider.html) works by providing filesystems via SPI. > Ideally one would just write the appropriate classes and drop them on the > classpath . This allows somebody does to write something like: > > Paths.get('gz:/path/to/compressed.gz') > > This all works fine when done within a normal application but it fails > when used within GroovyConsole or just running a normal Groovy script. ONe > would expect the following just to work > > @Grab('org.ysb33r.nio:nio-gz-provider-commons:0.1') > @Grab('org.slf4j:slf4j-simple:1.7.5') > > import java.nio.file.* > > Paths.get('gz:/path/to/compressed.gz') > > However the following workaround is required > > @Grab('org.ysb33r.nio:nio-gz-provider-commons:0.1') > @Grab('org.slf4j:slf4j-simple:1.7.5') > > import java.nio.file.* > > FileSystem fs > > try { > fs = FileSystems.getFileSystem(gzURI) > } catch(FileSystemNotFoundException) { > fs = FileSystems.newFileSystem(gzURI,[:],this.class. > classLoader.parent.parent) > } > > Path gzPath = fs.provider().getPath(gzURI) > > NOTE: Using @GrabConfig(initContextClassLoader=true, > systemClassLoader=true) does not solve the problem in this case > > > At Gr8Conf I sat with with Andres, Jochen and Guillaume to work through > this. The issue that that providers are loaded via the system class loader, > whereas with GroovyConsole and command-line Groovy it will be loaded via an > instance of RootLoader. This leads to one having to manually loading the > filesystem. > > From the point of view of someone using NIO2 providers this is surprising > behaviour. One would expect it just to work out of the box (as per the > Javadoc for FileSystemProvider). > > My question is now. Is there something that can be done to way > GroovyConsole and Groovy scripts are started so that the expectd behaviour > of NIO2 providers can be obtained? (Maybe adding an additional method to > GrabConfig?). > > Groovy luck. > > -- > Schalk W. Cronjé > Twitter / Ello / Toeter : @ysb33r > >
