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Challenge: Java Advanced Language Features - Working with Streams and Optional

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Lab Info
Last updated
Jun 24, 2025
Duration
12m

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Table of Contents
  1. Challenge

    Working with Streams and Optional

    The method getCustomerName is supposed to find a customer in a list by id and then return the name of the customer if it was found. If the customer cannot be found, return the string "UNKNOWN".

    Solution

    You can find the solution to this exercise in the **Solution** directory in the filetree.
    
    To run your methods, click the `Run` button in the bottom right of the terminal to run the code in `App.java`.
About the author

Jesper de Jong is an independent, experienced software developer and architect who designs and builds efficient, scalable, and high-quality server-side software for the JVM in Java and Scala. He loves the creativity of inventing and building software systems and loves to teach and share his knowledge with the software development community.

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