Stream.map() + Java Generics – Everything You’ve Been Missing! | Stream API | Generics | Java 8

Описание: In this comprehensive 2-hour deep dive, we break down everything you didn't know you needed to fully understand the map() method in Java’s Stream API — especially the confusing generics like ? super T and ? extends R.

Whether you're a beginner trying to understand functional programming in Java, or an experienced developer struggling with Java Generics and PECS (Producer Extends, Consumer Super), this tutorial is for you.

⏱️ Timestamps
-------------------------
00:00:00 - Stream.map() + Java Generics Deep Dive – Everything You’re Missing!
00:02:21Practical Examples: Real-World Mapping with Java Streams
00:11:02 - How to Create a Custom map() Clone in Java
00:26:03 - Making map() Method Fully Generic – Step-by-Step
00:36:11 - Understanding `? super T` – map() Function Input Explained
01:08:20 - PECS Principle Applied to Java Stream.map()
01:27:25 - Why map() Doesn't Use `? extends R` as Input
01:38:39 - map() Return Type: What `? extends R` Really Means
01:47:13 - Building a Stream API map() Clone from Scratch

💡 What You’ll Learn
✅ How Java Stream.map() works under the hood
✅ What ? super T and ? extends R really mean
✅ How to apply the PECS principle in real-world code
✅ How to write your own version of the map() method
✅ Why understanding generics is key to mastering streams

#javatutorial #javastreams #javagenerics

For More free/paid courses visit
www.seleniumexpress.com

LINKS AND FREE LEARNING RESOURCES
========
Watch my new mock interview series for java developers
   • Java interview questions and answers for e...  

Watch Spring boot Hot topics
   • @Reposicotry Vs @Service | Spring Boot | s...  

Java Interview / Question and Answer series
   • Java collections interview questions | Why...  

Explain spring Bean Lifecycle
   • REAL-TIME: Spring Bean life cycle using @P...  

spring core
   • Spring framework tutorial for beginners wi...  

spring mvc
   • Spring MVC course introduction || Understa...  

spring mvc intermediate
   • [INTERMEDIATE] Spring MVC Course Preview |...  

Spring JDBC
   • Spring JDBC Course Preview || Let’s talk d...  

spring live project
   • #1 Build and Deploy A Spring Project Step ...  

SPRING SECURITY COURSE[NEW]
   • Spring Security Course Preview | Learn to ...  

For more courses visit
https://www.seleniumexpress.com

Any time you are getting stuck with issues, Feel free to ask for support.
You can send mail to [email protected]

you can ping me on my Facebook page
  / seleniumexpress  

Make sure to join my private Facebook page (Ask me here)
“SeleniumExpress - Support"
  / 187000222361579  

you can ask for support in my website forum
https://www.seleniumexpress.com

Subscribe to my youtube channel

Follow me on Insta
  / selenium_express