PathMather.matches(Path) don't agree with Pattern.matches(String,CharSequence) for some of predefined character classes. Please see the following test:
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import java.nio.file.FileSystem;
import java.nio.file.FileSystems;
import java.nio.file.Paths;

public class miniTest {
    public static void main(String[] args) {
        FileSystem fs = FileSystems.getDefault();
        System.out.println(fs.getPathMatcher("regex:foo\\d+").matches(Paths.get("foo012")));
        System.out.println(fs.getPathMatcher("regex:fo\\so").matches(Paths.get("fo o")));
        System.out.println(fs.getPathMatcher("regex:\\w+").matches(Paths.get("foo")));
    }
}
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It's output is
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false
false
false
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while all the results of the corresponding Pattern.matches(String, CharSequence) are true