You could be getting a failed delete for a number of reasons; the file could be locked by the file system, you may lack permissions, or could be open by another process etc.
If you're using Java 7 or above you can use the javax.nio.*
API; it's a little more reliable & consistent than the legacy java.io.File
classes:
Path fp = file.toPath();
Files.delete(fp);
If you want to catch the possible exceptions:
try {
Files.delete(path);
} catch (NoSuchFileException x) {
System.err.format("%s: no such" + " file or directory%n", path);
} catch (DirectoryNotEmptyException x) {
System.err.format("%s not empty%n", path);
} catch (IOException x) {
// File permission problems are caught here.
System.err.println(x);
}
Check the docs for more info on IO in Java 7