JDK 9 and the shift from JDK 8

JDK 9 introduced modules, jlink, jmod, and jshell, fundamentally changing how the platform could be structured and delivered.

Why JDK 9 mattered

The release in context

JDK 9 introduced modules, jlink, jmod, and jshell, fundamentally changing how the platform could be structured and delivered.

JPMSjlinkjshell

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JDK 9 introduced modules, jlink, jmod, and jshell, fundamentally changing how the platform could be structured and delivered.
This is the moment where the public JRE story changed and the JDK became more explicitly modular, inspectable, and customizable.

Platform stack

JDK 9 architecture preview

This larger diagram expands the smaller JDK badge into a layered platform view showing how the development kit, runtime, virtual machine, APIs, tools, and supporting subsystems fit together for this release.

Open in new window Back to JDK timeline

Previous-version diff

What changed from JDK 8 to JDK 9

This is the moment where the public JRE story changed and the JDK became more explicitly modular, inspectable, and customizable.

Platform movement

This is the moment where the public JRE story changed and the JDK became more explicitly modular, inspectable, and customizable.
This release is best understood as a turning point in how developers thought about the Java platform, not just as a routine toolkit increment.

Matrix slice

Quick comparison table: JDK 8 vs JDK 9

This side-by-side view turns the source evolution matrix into a faster way to see which language, tooling, runtime, and platform layers moved between these two releases.

Area	Component	JDK 8	JDK 9	Why it stands out
Platform	JDK 9	Previous baseline	Current release	This is the moment where the public JRE story changed and the JDK became more explicitly modular, inspectable, and customizable.

Structured comparison

Grouped reading of the release shift

This release is best understood as a turning point in how developers thought about the Java platform, not just as a routine toolkit increment.

Platform evolution

New in JDK 9

JPMS

Updated by JDK 9

jlink

Historical platform profile

Release narrative

JDK 9 introduced modules, jlink, jmod, and jshell, fundamentally changing how the platform could be structured and delivered.

This is the moment where the public JRE story changed and the JDK became more explicitly modular, inspectable, and customizable.

JPMSjlinkjshell

Why it mattered later

Why JDK 9 matters in the JDK timeline

This release is best understood as a turning point in how developers thought about the Java platform, not just as a routine toolkit increment.

This release is best understood as a turning point in how developers thought about the Java platform, not just as a routine toolkit increment.
This is the moment where the public JRE story changed and the JDK became more explicitly modular, inspectable, and customizable.

Continue through the platform story

Common JDK Return to the JDK timeline and compare this release with neighboring toolkit milestones. Common Java See the language-level release story associated with this JDK version. Common JVM & Class File Connect this platform release with bytecode and runtime compatibility changes. Compatibility Cross-check this JDK version against Java, JLS, and class file milestones.