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

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Path Info

Duration

12m

Last updated

Jun 24, 2025

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`.

Author

Jesper de Jong

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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