03. [20 marks: 10 for each method] Develop a class BackupRestore that has two static methods: public static int backup (String filename, double partSize) public static int restore (String filename, int numberOfPieces) The backup method backs up huge files by splitting them into smaller pieces that may fit into storage devices with different capacities (e.g., 700 mb for CD-Rs). The size of each piece is equal to partSize megabytes. The method creates the output files filename.1, filename.2, etc. and then returns an integer representing the number of files created. The restore methods does the opposite. It combines filename.1, filename.2, etc. into filename. The method returns an integer representing the total size of the file filename. Most questions a re based on/ta ken fromthe exercises a nd examples listed in the textbook used bythe course. In both methods, if an IOException occurs, display an error message and return -1. Use buffer classes to improve performance. Try your code on the course syllabus (syllabus.pdf), i.e., split it into pieces of e.g. 0.25 MB size, delete the original file, and then combine your pieces back again and open the file to see if your code works