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Challenge: Java Advanced Language Features - Using Sealed Interfaces and Records

Lab Info
Table of Contents
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Challenge
Use a Sealed Interface and Records
Interface
Transaction
is a sealed interface with two subclasses:Purchase
andRefund
.Class
TransactionService
contains a methodcalculateNetAmount
to calculate the net amount of a list of purchase and refund transactions.Solution
To run your methods, click the **Run** button in the bottom right of the terminal to run the code in `App.java`.You can find the solution to this exercise in the **CompletedExercise** directory in the filetree.
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