Chapter 4. Red Hat build of OpenJDK features

The latest Red Hat build of OpenJDK 17 release might include new features. Additionally, the latest release might enhance, deprecate, or remove features that originated from previous Red Hat build of OpenJDK 17 releases.

Red Hat build of OpenJDK enhancements

Red Hat build of OpenJDK 17 provides enhancements to features originally created in previous releases of Red Hat build of OpenJDK.

Reduced risk of JVM crash when using GregorianCalendar.computeTime()

In Red Hat build of OpenJDK 17.0.7, a virtual machine crash could occur when using the GregorianCalendar.computeTime() method (JDK-8307683). Even though an old issue is the root cause of this JVM crash, a recent fix for a rare issue in the C2 compiler (JDK-8297951) significantly increased the probability of the JVM crash. To mitigate risk, the Red Hat build of OpenJDK 17.0.8 release excludes the fix for the C2 compiler. Once the root cause of the JVM crash is resolved (JDK-8307683), Red Hat build of OpenJDK will reintroduce the fix for the C2 compiler (JDK-8297951).

See JDK-8308884 (JDK Bug System).

Support for GB18030-2022

The Chinese Electronics Standardization Institute (CESI) recently published GB18030-2022 as an update to the GB18030 standard, synchronizing the character set with Unicode 11.0. The GB18030-2022 standard is now the default GB18030 character set that Red Hat build of OpenJDK 17.0.8 uses. However, this updated character set contains incompatible changes compared with GB18030-2000, which previous releases of Red Hat build of OpenJDK 17 used. From Red Hat build of OpenJDK 17.0.8 onward, if you want to use the previous version of the character set, ensure that the new system property jdk.charset.GB18030 is set to 2000.

See JDK-8301119 (JDK Bug System).

Enhanced ZIP performance

The Red Hat build of OpenJDK 17.0.8 release includes enhanced checks on the ZIP64 fields of .zip files. If these checks cause failures on trusted .zip files, you can disable these checks by setting the new system property jdk.util.zip.disableZip64ExtraFieldValidation to true.

JDK bug system reference ID: JDK-8302483.

Enhanced validation of JAR signature

You can now configure the maximum number of bytes that are allowed for the signature-related files in a Java archive (JAR) file by setting a new system property, jdk.jar.maxSignatureFileSize. By default, the jdk.jar.maxSignatureFileSize property is set to 8000000 bytes (8 MB).

JDK bug system reference ID: JDK-8300596.

GTS root certificate authority (CA) certificates added

In the Red Hat build of OpenJDK 17.0.8 release, the cacerts truststore includes four Google Trust Services (GTS) root certificates:

See JDK-8307134 (JDK Bug System).

Microsoft Corporation root CA certificates added

In the Red Hat build of OpenJDK 17.0.8 release, the cacerts truststore includes two Microsoft Corporation root certificates:

See JDK-8304760 (JDK Bug System).

TWCA root CA certificate added

In the Red Hat build of OpenJDK 17.0.8 release, the cacerts truststore includes the Taiwan Certificate Authority (TWCA) root certificate:

See JDK-8305975 (JDK Bug System).

New JFR event jdk.SecurityProviderService

Calls to the java.security.Provider.getService(String type, String algorithm) method now trigger a new JFR event, jdk.SecurityProviderService.

The jdk.SecurityProviderService event contains the following three fields:

The jdk.SecurityProviderService event is disabled by default. You can enable this event by using the standard JFR configuration files and options.

See JDK-8254711 (JDK Bug System).