任何人都可以帮我修改我的Java代码吗？

Okay to make this clearer this is what i need done to my entire program. I need main to restore any calculators that are in the file "calc.bak" before presenting the user with a menu and main should save all calculators that exist in that same file (overwrite as appropriate) just before exiting. I also need to give the user the option to create a brand new calculator, name it, and add a function to it from an already existing collection (which are my Add, multiply, and divide). I also need the user to create their own function by designing and naming a combination of any pair of functions. The ouput of the first function would necessarily be input to the second function. For example, the user can create a new function called "addmult" that calls the add function (which prompts for two numbers and adds them) and establishes the sum as one of the operands for the multiply function (which would have to prompt for its second operand). Okay to make this clearer this is what i need d