Here are 2 ways(both are OS independent.)
Using Paths : Since 1.7
Path p = Paths.get(<Absolute Path of Linux/Windows system>);
String fileName = p.getFileName().toString();
String directory = p.getParent().toString();
Using FilenameUtils in Apache Commons IO :
String name1 = FilenameUtils.getName("/ab/cd/xyz.txt");
String name2 = FilenameUtils.getName("c:\\ab\\cd\\xyz.txt");