Releasing File resources after "new File()"

Question

Hi, I'm experiencing the following problem. I'd like to list the properties of files in a directory, so I do something like
File dir = new File(".");
String[] files = dir.list();
for(int i = 0; i < files.length; i++){
System.out.println(new File(files).lastModified());
I gather these calls to "new File()" do hold some read locks to the files, when are these locks released? at GC time? is there anyway to force/guarantee the release?

Answer 1

I gather these calls to "new File()" do hold some
read locks to the files, No, they don't. File just has metada about the file--name, path, size, etc. It doesn't open the file or lock it or anything.
The ones you need to clean up are the Input/OutputStreams and Readers and Writers. Those have close() methods. There's also java.nio.channels.FileLock and associated classes mentioned in its docs.