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JavaDoc JAR package is published together with compiled classes to the ONAP Nexus repository. You can download JavaDoc in your IDE so you will get documentation hints. Alternatively you can use Maven Dependency plugin (classifier=javadoc).

Which Java version is supported?

For now we are compiling SDK using JDK 8. Hence we advice to use SDK on JRE 8. However, we are using parts of it on JRE 11 and it still works.

Are you sure Java 8 is supported? I can see a debug log from Netty.

If you have enabled a debug log level for Netty packages you might have seen the following log:

[main] DEBUG i.n.util.internal.PlatformDependent0 - jdk.internal.misc.Unsafe.allocateUninitializedArray(int): unavailable prior to Java9

Background: this is a result of  moving sun.misc.Unsafe to jdk.internal.misc.Unsafe in JDK 9, so if Netty wants to support both pre and post Java 9 it has to check the JDK version and use the class from available package.

It does not have any impact on SDK. SDK still works with this log. You might want to change log lever for io.netty package to INFO.

CBS Client

When cbsClient.updates() will yield an event?

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