me think!: July 2018

Monday 30 July 2018

Homage to the 36 trillion, 119 thousand, 500 Amitabha Buddhas

Homage to the 36 trillion, 119 thousand, 500 Amitabha Buddhas

Homage to the 36 trillion, 119 thousand, 500 Amitabha Buddhas

Homage to the 36 trillion, 119 thousand, 500 Amitabha Buddhas

- wong chee tat :)

Homage to the 36 trillion, 119 thousand, 500 Amitabha Buddhas

Sunday 29 July 2018

JDK 8u181 Update Release Notes

JDK 8 Update Release Notes

Java™ SE Development Kit 8, Update 181 (JDK 8u181)

July 17, 2018

The full version string for this update release is 1.8.0_181-b13 (where "b" means "build"). The version number is 8u181.

IANA Data 2018e

JDK 8u181 contains IANA time zone data version 2018e. For more information, refer to Timezone Data Versions in the JRE Software.

Security Baselines

The security baselines for the Java Runtime Environment (JRE) at the time of the release of JDK 8u181 are specified in the following table:

JRE Family Version	JRE Security Baseline (Full Version String)
8	1.8.0_181-b13
7	1.7.0_191-b08
6	1.6.0_201-b07

JRE Expiration Date

The JRE expires whenever a new release with security vulnerability fixes becomes available. Critical patch updates, which contain security vulnerability fixes, are announced one year in advance on Critical Patch Updates, Security Alerts and Bulletins. This JRE (version 8u181) will expire with the release of the next critical patch update scheduled for October 16, 2018.

For systems unable to reach the Oracle Servers, a secondary mechanism expires this JRE (version 8u181) on November 16, 2018. After either condition is met (new release becoming available or expiration date reached), the JRE will provide additional warnings and reminders to users to update to the newer version. For more information, see JRE Expiration Date.

Removed Features and Options

other-libs/javadb

➜ Removal of Java DB

Java DB, also known as Apache Derby, has been removed in this release.

We recommend that you obtain the latest Apache Derby directly from the Apache project at:

https://db.apache.org/derby

JDK-8197871 (not public)

Changes

core-libs/javax.naming

➜ Improve LDAP support

Endpoint identification has been enabled on LDAPS connections.

To improve the robustness of LDAPS (secure LDAP over TLS ) connections, endpoint identification algorithms have been enabled by default.

Note that there may be situations where some applications that were previously able to successfully connect to an LDAPS server may no longer be able to do so. Such applications may, if they deem appropriate, disable endpoint identification using a new system property:com.sun.jndi.ldap.object.disableEndpointIdentification.

Define this system property (or set it to true) to disable endpoint identification algorithms.

JDK-8200666 (not public)

core-libs/java.io:serialization

➜ Better stack walking

New access checks have been added during the object creation phase of deserialization. This should not affect ordinary uses of deserialization. However, reflective frameworks that make use of JDK-internal APIs may be impacted. The new checks can be disabled if necessary by setting the system property jdk.disableSerialConstructorChecks to the value "true". This must be done by adding the argument -Djdk.disableSerialConstructorChecks=true to the Java command line.

JDK-8197925 (not public)

Bug Fixes

The following are some of the notable bug fixes included in this release:

core-svc/debugger

➜ Unable to use the JDWP API in JDK 8 to debug JDK >=9

The implementation of VirtualMachineImpl.canGetInstanceInfo() has been corrected, so it is now able to see JDK JVMs >= JDK 9.

This correction allows certain debugger agents to operate correctly without any action required from a user (developer).

See JDK-8197943

hotspot/gc

➜ JVM Crash during G1 GC

A klass that has been considered unreachable by the concurrent marking of G1, can be looked up in the ClassLoaderData/SystemDictionary, and its _java_mirror or _class_loader fields can be stored in a root or any other reachable object making it alive again. Whenever a klass is resurrected in this manner, the SATB part of G1 needs to be notified about this, otherwise, the concurrent marking remark phase will erroneously unload that klass.

In this particular crash, while G1 was doing concurrent marking and had prepared its list of unreachable classes, JVMTI on a Java thread could traverse classes in the CLD and store thread-local JNIHandles for the java_mirror of the loaded classes. G1 did not have knowledge of these thread-local JNIHandles, and in the remark phase, it unloaded the classes per its prior knowledge of unreachable classes. When these JNIHandles were later scanned, it lead to a crash.

This fix for JDK-8187577 informs G1's SATB that a klass has been resurrected and it should not be unloaded.

See JDK-8187577

hotspot/gc

➜ Better stability with older NUMA libraries (-XX+UseNuma)

A fix included in JDK 8 Update 152 introduced a regression that might cause the HotSpot JVM to crash during startup when the UseNUMA flag is used on Linux systems with versions of libnuma older than 2.0.9. This issue has been resolved.

See JDK-8198794

This release also contains fixes for security vulnerabilities described in the Oracle Critical Patch Update. For a more complete list of the bug fixes included in this release, see the JDK 8u181 Bug Fixes page.

- Link:

- wong chee tat :)