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Gopi Gorantala

I'm Gopi — 15+ years in Java, building Kafka and Flink platforms for banks, where one lost event is a financial discrepancy. I write javahandbook.com because the guides I needed didn't exist. Everything here is tested against a real cluster first.

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How To Write Lambda Expressions

This lesson introduces the basic lambda expression structure with tips to write efficient code.

Java Functional Programming with Lambdas and Streams API

Java 8 is bundled with massive features and improvements to the JDK, JRE and more. It introduced functional programming in Java.

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What Are Lambda Expressions?

This is an introductory lesson on lambda expressions. You will learn about the lambda operator, expression, syntaxes and more!

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Power Of Two (Exercise Problem)

This is an exercise problem for your practice. Try to come up with an approach and solve it by yourself. Good Luck!

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User-Defined Customer Interface (Exercise Problem)

This is an exercise problem for your practice. Try to come up with an approach and solve it by yourself. Good Luck!

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What Are UnaryOperator And BinaryOperator's?

Unary and Binary operators are the other two functional interfaces that most developers are interested in.

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Course Overview: Functional Programming in Java

This course deep-dives into each of the functional programming concepts that got introduced in the Java programming language.

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Introduce Yourself To Java Functional Programming

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BiFunction Interface

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What Is a Predicate Interface In Java?