I dont know where to start with this problem so I have a super class(Transaction) that has a constructor and I have 2 sub classes (rental and return )they both have the same constructor as the super but they have a toString method that is almost the same but not really . The rental has the id num ,format of the disc and the date and then the fee. while in the rent I have the id, format , fee. How can I write those method so I dont have duplicate codes and it easy to change and understand? I also want to get the total fee after the toString method at the end? can some one pleas help I would really be thankful !