Try to use org.apache.commons.io.FileUtils (General file manipulation utilities). Facilities are provided in the following methods:
(1) FileUtils.moveDirectory(File srcDir, File destDir) => Moves a directory.
(2) FileUtils.moveDirectoryToDirectory(File src, File destDir, boolean createDestDir) => Moves a directory to another directory.
(3) FileUtils.moveFile(File srcFile, File destFile) => Moves a file.
(4) FileUtils.moveFileToDirectory(File srcFile, File destDir, boolean createDestDir) => Moves a file to a directory.
(5) FileUtils.moveToDirectory(File src, File destDir, boolean createDestDir) => Moves a file or directory to the destination directory.
It's simple, easy and fast.