Update Release Notes

Java SE 6 Update 23

The full internal version number for this update release is 1.6.0_23-b05 (where "b" means "build"). The external version number is 6u23.


Java SE 6u23 contains enhancements for your Java applications:

  • Improved performance and stability
  • Enhanced support for right-to-left languages

OlsonData 2010l

Java SE 6u23 contains Olson time zone data version 2010l. For more information, refer to Timezone Data Versions in the JRE Software .

Security Baseline

Java SE 6u23 specifies the following security baselines for use with Java Plug-in technology:

JRE Family Version Java SE Security Baseline Java for Business Security Baseline
6 1.6.0_22 1.6.0_22
5.0 1.5.0_22 1.5.0_26
1.4.2 1.4.2_19 1.4.2_28

For more information about the security baseline, see Deploying Java Applets With Family JRE Versions in Java Plug-in for Internet Explorer .

Java Hotspot VM 19.0

Java SE 6u23 includes version 19.0 of the Java HotSpot Virtual Machine with improvements to overall performance and reliability.

Java VisualVM 1.3.1

Java VisualVM based on VisualVM 1.3.1 is included in Java SE 6u23. This release introduces the following features and enhancements:

  • Added Java version and vendor information to the application Overview view
  • Built on NetBeans Platform and profiler 6.9.1

Menu Item Corrections for Right-to-Left Languages

Several bugs in the non-default alignment and text orientation for the menu items in Swing have been fixed, as this is particularly important for right-to-left languages such as Arabic.

Another issue corrected is the position of the icon and the text. For the non-default positions the text used to overlap the icon in a menu item, this is no longer the case.

All platform Look and Feel configurations will now handle menu items in right-to-left language situations. These fixes have been tested through their inclusion in the JDK 7 development release, but this is the first time they have been available via JDK 6.

Additional Languages Support in Linux Systems

Added support for SuSE Linux Enterprise Server 10 and 11 on Chinese (Simplified), Chinese (Traditional), Japanese, and Korean locales.

Support for Compressed Oops

Compressed oops is supported and enabled by default in Java SE 6u23 and later releases. See Java HotSpot VM Performance Enhancements page for more information.

Bug Fixes

Java SE 6u23 does not contain any additional fixes for security vulnerabilities to its previous release, Java SE 6u22. Users who have Java SE 6u22 have the latest security fixes and do not need to upgrade to this release to be current on security fixes.

For other bug fixes, see the Java SE 6u23 Bug Fixes page.