Functional Programming in Java : Java Lambdas and Streams

Description

UPDATE February 2023 – streams assignment added!

UPDATE June 2022 – I have just published my Java 17, Java 11, Advanced Java 8 (1Z0-829,1Z0-819,1Z0-809) course. Lambdas and Streams are contained in that much larger course. Please check out the new course as it may be much better value.

UPDATE April 2022 – lambdas/method references assignment added!

This course is a systematic approach to explaining in both notes format and code examples, lambda expressions and streams in Java. All the code samples are included.

Topics include:

Lambdas:
- Functional Interfaces
- Lambdas and their relationship to Functional Interfaces
- Lambdas in code using a custom Functional Interface
- Lambdas in code using the pre-defined API Functional Interfaces:
  - Predicate/BiPredicate
  - Supplier
  - Consumer/BiConsumer
  - Function/BiFunction
  - UnaryOperator and BinaryOperator
- final and “effectively final”
- Method References:
  - bound
  - unbound
  - static
  - constructor
  - context and it’s effect in understanding method references
Streams:
- Pipelines
- Laziness
- Creating streams
- Terminal operations:
  - reduce()
  - collect()
    - Collectors.toMap()
    - Collectors.groupingBy()
    - Collectors.partitioningBy()
- Intermediate operations:
  - filter(), distinct(), limit()
  - map(), flatMap(), sorted()
- Primitive streams:
  - Creating
  - API
  - Functional Interfaces
  - Mapping between primitive streams
  - Mapping between primitive streams and Object streams and vice versa
- Optionals
- Parallel streams

This course is geared towards Java Certification i.e. the Predicate lambda sections would suit Java 8 OCA (1Z0-808). The remaining lambda sections and the streams sections would suit both Java 8 OCP (1Z0-809) and Java 11 (1Z0-819). This course explains the concepts through small, simple, targeted code examples.

For those who don’t know me, my “Complete Java 8 OCA (1Z0-808) Java Certification Course” is, at the time of writing, the highest rated Java 8 OCA course on Udemy. I am a lecturer since 2002 and have taught the OCA and OCP syllabii since 2013 on behalf of a highly regarded software company. On completion of the courses with me, graduates then face the company’s own internal Java Certification exam (similar in style to Oracle’s). I have no visibility into the questions they will face. It is a 3 hour long intensive exam. The company are delighted with the pass rate (100% since year 1).

I love teaching and this course has all my experience in explaining lambdas and streams in Java. I am delighted that Enthuware (the excellent Java certification training tool), have, in their explanations, linked to my YouTube channel.

Who this course is for:

Anyone interested in learning Lambdas and Streams (the Functional Programming aspects of Java 8).

Requirements

Intermediate Java. Whereas my “Java 8 OCA (1Z0-808) Course” starts at the beginning, this assumes that the learner has a reasonable level of Java.
To make understanding lambdas easier, a familiarity with anonymous inner classes would help. That said, lambdas are contrasted with anonymous inner class syntax in the course.

Last Updated 1/2023