JDK 12 - Pitfalls For The Unwary

Explore the significant changes and potential pitfalls in Java Development Kit (JDK) versions 9 through 12 in this comprehensive conference talk. Dive into the new Java Platform Module System, its impact on application migration, and strategies for adapting to the modular architecture. Learn about important modifications to Java language syntax, class libraries, and JVM options across these releases. Understand the implications of the new JDK release cadence on Java support and production version choices. Discover techniques for identifying deprecated API usage, reversing encapsulation, and finding dependencies using tools like jdeps. Examine changes in JDK/JRE file structure, version string format, and non-programmatic issues such as JVM logging and flags. Gain insights into local variable type inference, command-line flags, and the differences between Oracle JDK and OpenJDK. Address the challenges of migrating to JDK 11 or 12 and explore alternatives like Zulu Community Edition to ensure a smooth transition for your Java applications.

Intro
JDK 12 Functionality
JDK 9: Big And Small Changes
JDK 9 Onwards And Compatibility
Java Platform Module System (JPMS) . The core Java libraries are now a set of modules (JEP 220)
Migrating Applications to JPMS
Reversing Encapsulation
Finding Dependencies: jdeps
Using "Missing" Modules
Milling Project Coin (JEP 213)
Deleted Deprecated Methods
Finding Deprecated API Use
JDK/JRE File Structure (JEP 220)
New Version String Format (JEP 223)
Non-Programmatic Issues
JVM Logging
Replaced JVM Flags
Deprecated JVM Flags
Local Variable Type Inference
Command Line Flags
Oracle JDK & OpenJDK
Major Absent Features
Tools Affected
Command Line-XX Flags
Migrating To JDK 11 or 12
Zulu Community Edition