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JDK 6 • 2006 • Java 6
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JDBC 4.0Scripting EngineJAXB 2.0JAX-WSCompiler APIVisualVM

JDK 6 and the shift from JDK 5

J2SE renamed to Java SE. JDBC 4.0, JSR-223 Scripting Engine, JAXB 2.0, JAX-WS, Compiler API (JSR-199), Desktop API. OpenJDK open-sourced.

Why JDK 6 mattered

The release in context

J2SE renamed to Java SE. JDBC 4.0, JSR-223 Scripting Engine, JAXB 2.0, JAX-WS, Compiler API (JSR-199), Desktop API. OpenJDK open-sourced.

JDBC 4.0Scripting EngineJAXB 2.0JAX-WSCompiler APIVisualVM
  • J2SE renamed to Java SE. JDBC 4.0, JSR-223 Scripting Engine, JAXB 2.0, JAX-WS, Compiler API (JSR-199), Desktop API. OpenJDK open-sourced.
  • Key release highlights included JDBC 4.0, Scripting Engine, JAXB 2.0, JAX-WS.
  • Compared with JDK 5, the most visible shifts included JAX-WS 2.0, Scripting (JSR-223), @Override on interfaces.
  • Java SE name introduced. OpenJDK GPL release begins. Scripting engine enables Groovy/JRuby integration.
  • Rather than redefining the platform, it made the existing JDK feel more polished and dependable for production environments.
Platform stack

JDK 6 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.

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Previous-version diff

What changed from JDK 5 to JDK 6

Rather than redefining the platform, it made the existing JDK feel more polished and dependable for production environments.

lang and util Base Libraries

  • javax.script appeared in JDK 6, adding a new capability in lang and util base libraries.
  • javax.tools appeared in JDK 6, adding a new capability in lang and util base libraries.
  • javax.xml.ws appeared in JDK 6, adding a new capability in lang and util base libraries.
  • java.sql was updated in JDK 6, showing active movement in lang and util base libraries.

Integration Libraries

  • JAX-WS 2.0 appeared in JDK 6, adding a new capability in integration libraries.
  • Scripting (JSR-223) appeared in JDK 6, adding a new capability in integration libraries.
  • JAXB 2.0 was updated in JDK 6, showing active movement in integration libraries.
  • JDBC 4.0 was updated in JDK 6, showing active movement in integration libraries.

Tools & Tool APIs

  • JMC (early) appeared in JDK 6, adding a new capability in tools & tool apis.
  • VisualVM appeared in JDK 6, adding a new capability in tools & tool apis.
  • jconsole was updated in JDK 6, showing active movement in tools & tool apis.
  • JPDA Debugger moved from active change in JDK 5 into a more stable baseline by JDK 6.
Matrix slice

Quick comparison table: JDK 5 vs JDK 6

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 5 JDK 6 Why it stands out
Integration Libraries JAX-WS 2.0 Not present NEW JAX-WS 2.0 appeared in JDK 6, adding a new capability in integration libraries.
Integration Libraries Scripting (JSR-223) Not present NEW Scripting (JSR-223) appeared in JDK 6, adding a new capability in integration libraries.
Java Language Features @Override on interfaces Not present NEW @Override on interfaces appeared in JDK 6, adding a new capability in java language features.
Other Base Libraries Compiler API (JSR-199) Not present NEW Compiler API (JSR-199) appeared in JDK 6, adding a new capability in other base libraries.
Other Base Libraries Pluggable Annotation Processing Not present NEW Pluggable Annotation Processing appeared in JDK 6, adding a new capability in other base libraries.
Tools & Tool APIs JMC (early) Not present NEW JMC (early) appeared in JDK 6, adding a new capability in tools & tool apis.
Tools & Tool APIs VisualVM Not present NEW VisualVM appeared in JDK 6, adding a new capability in tools & tool apis.
User Interface Toolkits Desktop API Not present NEW Desktop API appeared in JDK 6, adding a new capability in user interface toolkits.
lang and util Base Libraries javax.script Not present NEW javax.script appeared in JDK 6, adding a new capability in lang and util base libraries.
lang and util Base Libraries javax.tools Not present NEW javax.tools appeared in JDK 6, adding a new capability in lang and util base libraries.
Java Language Features Annotations NEW UPD Annotations was updated in JDK 6, showing active movement in java language features.
User Interface Toolkits Swing UPD UPD Swing was updated in JDK 6, showing active movement in user interface toolkits.
JVM: Execution Engine & GC CMS GC NEW Present CMS GC carried forward from JDK 5 and settled into the baseline by JDK 6.
JVM: Execution Engine & GC HotSpot JIT (C1+C2) UPD Present HotSpot JIT (C1+C2) moved from active change in JDK 5 into a more stable baseline by JDK 6.
Structured comparison

Grouped reading of the release shift

Java SE name introduced. OpenJDK GPL release begins. Scripting engine enables Groovy/JRuby integration.

lang and util Base Libraries
New in JDK 6
  • javax.script
  • javax.tools
  • javax.xml.ws
  • java.lang.StringBuilder
  • java.lang.instrument
Updated by JDK 6
  • java.sql
  • javax.swing
  • javax.xml.bind
  • java.lang (Generics)
  • java.util (Generics)
Integration Libraries
New in JDK 6
  • JAX-WS 2.0
  • Scripting (JSR-223)
Updated by JDK 6
  • JAXB 2.0
  • JDBC 4.0
Tools & Tool APIs
New in JDK 6
  • JMC (early)
  • VisualVM
  • jmap
  • jps
  • jstack
Updated by JDK 6
  • jconsole
  • JPDA Debugger
Historical platform profile

Release narrative

J2SE renamed to Java SE. JDBC 4.0, JSR-223 Scripting Engine, JAXB 2.0, JAX-WS, Compiler API (JSR-199), Desktop API. OpenJDK open-sourced.

Java SE name introduced. OpenJDK GPL release begins. Scripting engine enables Groovy/JRuby integration.

JDBC 4.0Scripting EngineJAXB 2.0JAX-WSCompiler APIVisualVM
Why it mattered later

Why JDK 6 matters in the JDK timeline

This release fits into the steady JDK cadence where tooling, runtime behavior, and delivery capabilities evolve one step at a time.

  • JDK 6 sits in the timeline as a enterprise polish, which shaped how teams evaluated and adopted it.
  • It is commonly remembered for JDBC 4.0, Scripting Engine, JAXB 2.0.
  • Compared with JDK 5, it gives a clearer picture of how the JDK platform was evolving release by release.
  • Java SE name introduced. OpenJDK GPL release begins. Scripting engine enables Groovy/JRuby integration.
Related pages

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.