Migrating to Java 17 | Java 17 New Features & Skills

Course Objectives

This course combines expert lecture, real-world demonstrations and group discussions with machine-based practical labs and exercises.  Working in a hands-on learning environment led by our expert instructor, you will learn:

• The difference between LTS and non-LTS versions
• The (dis)advantages of preview features
• How to implement data objects using the new record type
• How to improve memory consumption through the use of compact Strings
• The use of the new strip and inBlank methods of the String class
• To define and use multi-line text blocks
• To use switch expressions to assign value
• To appy the yield keyword in a switch statement
• The concept of pattern matching
• How to apply pattern matching for instanceof
• All about sealed classes and interfaces
• Enhancements made to the try-with-resources construct
• To use the new Helpfull Nullpointer exceptions
• The thoughts behind the Java Modular system
• How to define and use modules
• How to use the ServiceLoader mechanism
• How to use the jdeps, jlink and jpackage tools to define self-contained Java applicaitons
• Methods added to the Collection and Stream API since Java 8
• The use of the var keyword and local variable type inference
• Private methods in interfaces
• The updated Deprecated method
• CompactNumberFormat

Course Prerequisites

This is an intermediate- level Java programming course, designed for experienced Java 8 developers who wish to get up and running with Java 11 immediately.  Attendees should have a working knowledge of developing Java 8 applications.

Take Before: Students sholuld have incoming skills equivalent to or should have attended this course as a pre-requsite:
•    TT2104-J8 Fast Track to Java 8 Programming for OO Experienced Developers

Course Agenda

Session: Introducing Java 17

Lesson: Versions and Features

• Overview of Java versions since Java 8
• (Non) LTS releases
• Preview features
• Java Language Specifications
• Java Specification Requests
• Java Enhancement Proposals

Lesson: Records

• Data objects in Java
• Introduce records as carrier of immutable data
• Defining records
• The Canonical constructor
• Compact constructors

Lesson: String and Text Blocks

• Discuss the definition of whitespace in Java
• Introduce the strip() methods of the String class
• The isBlank() and repeat() methods introduced in Java 11
• Using the lines() method to construct a Stream instance using a String
• Compact strings
• Introducing Text Blocks
• Indentation in text blocks

Lesson: Switch Expressions

• Switch Expressions
• Using yield
• Discuss switch fall through

Lesson: Pattern Matching

• Pattern Matching for instanceof
• Scope of variable when using pattern matching
• Refining Patterns in switch
• Dominance of pattern labels

Lesson: Sealed Classes

• Introduce sealed classes
• The sealed and permits modifier
• Sealed interfaces
• Sealed classes and pattern matching

Lesson: Exception Handling

• Enhanced try-with-resources
• Helpful NullpointerExceptions
• Excluding parameter names in error messages

Session: Java Modular System

Lesson: Introducing the Java Modular System

• Introduce the Java Modular System
• Platform modules
• The java.base Module
• Modular Development
• (Not) using Internal APIs

Lesson: The Module Descriptor

• The module descriptor module-info.java
• Defining module dependencies
• Readability and Accessibility
• Transitive dependencies and implied readability
• Exports and Accessibility
• Qualified exports
• Validity of the Module system

Lesson: Working with Modules

• Open modules for reflection
• Encapsulation and loose coupling
• Utilizing the ServiceLoader
• The 'provides' and 'with' reserved words

Lesson: jdeps, jlink and jpackage

• Module Path vs Class Path
• Unnamed modules
• Using jdpes to discover class and module dependencies
• Using jlink to create Self-Contained Java Applications
• Using jpackage to Create Native Java App Installers

Session: Working with Java 17

Lesson: Updates to Collections and Streams

• Introduce enhancements to the Collection API
• Unmodifiable Collections
• Introduce new functionality of the Stream API
• Explain new intermediate Stream operations (takeWhile, dropWhile)
• Collecting Stream elements into list using the new toList method

Lesson: Local Variable Type Inference

• Explain type inference
• Infering types of local variables
• The var reserved type name
• Benefits of using var
• Backward compatibilty

Lesson: More Updates

• private methods in interfaces
• The forRemoval and since attributes of the Deprecated annotation
• CompactNumberFormat
• Enhanced Pseudo-Random Number Generators