Course Overview

Migrating to Java 17 is a three-day hands-on course that will provide you with the updated skills you need to develop maintainable code that easily scales into multi-core environments. Geared for developers currently working in Java 8 or Java 11 who need to migrate their skills or applications to Java 17, this course will teach students everything they need to successfully master and implement the latest features and benefits of Java 17 and become an effective Java 17 developer.

There have been a lot of changes in the Java programming language since the release of Java 8 in March of 2014. This course explores the changes that will be most noticeable for Java developers who will make the transition from Java 8 to Java 17. It not only covers the changes to the programming language like the new var keyword, records, and sealed classes, it will also cover the Java modular system, introduced in Java 9 and the tooling that has been developed since then to allow the creation of self-contained Java applications.

Key Learning Areas

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 apply 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 applications
  • 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 Outline

Introducing Java 17
Versions and Features

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


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

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

Switch Expressions

  • Switch Expressions
  • Using yield
  • Discuss switch fall through

Pattern Matching

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

Sealed Classes

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

Exception Handling

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

Java Modular System
Introducing the Java Modular System

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

The Module Descriptor

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

Working with Modules

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

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

Working with Java 17
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

Local Variable Type Inference

  • Explain type inference
  • Inferring types of local variables
  • The var reserved type name
  • Benefits of using var
  • Backward compatibility

More Updates

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

Who Benefits

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.