Release notes for Red Hat build of OpenJDK 8.0.352

Red Hat will support select major versions of Red Hat build of OpenJDK in its products. For consistency, these are the same versions that Oracle designates as long-term support (LTS) for the Oracle JDK.

A major version of Red Hat build of OpenJDK will be supported for a minimum of six years from the time that version is first introduced. For more information, see the OpenJDK Life Cycle and Support Policy.

Red Hat build of OpenJDK in Red Hat Enterprise Linux (RHEL) contains a number of structural changes from the upstream distribution of OpenJDK. The Microsoft Windows version of Red Hat build of OpenJDK attempts to follow RHEL updates as closely as possible.

The following list details the most notable Red Hat build of OpenJDK 8 changes:

The latest Red Hat build of OpenJDK 8 release might include new features. Additionally, the latest release might enhance, deprecate, or remove features that originated from previous Red Hat build of OpenJDK 8 releases.

Red Hat build of OpenJDK new features and enhancements

Review the following release notes to understand new features and feature enhancements that the Red Hat build of OpenJDK 8.0.352 release provides:

Reference object changes and configurations

From Red Hat build of OpenJDK 8.0.352 onward, you can no longer clone Reference objects.

If you attempt to clone a reference object, the java.lang.ref.Reference::clone method throws a CloneNotSupportedException message.

If you want to copy an existing Reference object, you must use the constructor of the appropriate Reference subclass to create a Reference object. This ensures the new Reference object contains referent and reference queues that are identical to the target Reference object.

For the Red Hat build of OpenJDK 8.0.352 release, the java.lang.ref.Reference.enqueue method changes behavior. When application code calls the java.lang.ref.Reference.enqueue method, this method clears the Referent before it adds the object to the registered queue. After the Reference object is enqueued, code that expects the return value of java.lang.ref.Reference.get() to be non-null might throw a NullPointerException.

The Red Hat build of OpenJDK 8.0.352 release changes the behavior of PhantomReference objects, so that they are cleared before being enqueued in any associated queues. This is the same as the existing behaviour for SoftReference and WeakReference objects.

Enablement of TLSv1.3 for client roles

Red Hat build of OpenJDK 8.0.352 enables TLSv1.3 protocol support for client roles, by default.

From the Red Hat build of OpenJDK 8.0.272 release, TLSv1.3 protocol support for server roles was already enabled.

If you create a TLS client role in Red Hat build of OpenJDK 8.0.352 while keeping the default protocol setting, and TLSv1.3 is used in the connection established with the TLS server, compatibility issues might affect your application. The following list details common compatibility issues:

If you need to disable TLSv1.3 protocol support for your client role, complete one of the following actions:

sslSocket.setEnabledProtocols(new String[] {"TLSv1.2"});

sslEngine.setEnabledProtocols(new String[] {"TLSv1.2"});

SSLParameters params = sslSocket.getSSLParameters();
params.setProtocols(new String[] {"TLSv1.2"});
slsSocket.setSSLParameters(params);

jdk.httpserver.maxConnections system property

Red Hat build of OpenJDK 8.0.352 adds a new system property, jdk.httpserver.maxConnections, that fixes a security issue where no connection limits were specified for the HttpServer service, which can cause accepted connections and established connections to remain open indefinitely.

You can use the jdk.httpserver.maxConnections system property to change the HttpServer service’s behavior in the following ways:

Support for Microsoft Visual Studio 2017

From the Red Hat build of OpenJDK 8.0.352 release onward, the Windows JDK and JRE 1.8.0 releases are compiled with the Visual Studio 2017 toolchain, because this toolchain is currently supported by Microsoft.

For customers that rely on the Microsoft Visual Studio 2010 toolchain for compiling binaries, which Red Hat labels as the legacy toolchain, Red Hat continues to support these binaries. On the Software Details page, on the Red Hat Customer Portal, a file compiled with this toolchain contains a vs10 entry in its file name. For example, openjdk-1.8.0.345/java-1.8.0-openjdk-1.8.0.352-2.b08.redhat.windows.vs10.x86_64.zip.