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Illegal reflective access warnings when running Netty with Java 9

See original GitHub issue

Expected behavior

No warnings.

Actual behavior

Warnings when starting netty with java 9:

WARNING: An illegal reflective access operation has occurred
WARNING: Illegal reflective access by io.netty.util.internal.ReflectionUtil (file:/home/doom369/.m2/repository/io/netty/netty-common/4.1.16.Final/netty-common-4.1.16.Final.jar) to constructor java.nio.DirectByteBuffer(long,int)
WARNING: Please consider reporting this to the maintainers of io.netty.util.internal.ReflectionUtil
WARNING: Use --illegal-access=warn to enable warnings of further illegal reflective access operations
WARNING: All illegal access operations will be denied in a future release

with --illegal-access=warn enabled :

WARNING: Illegal reflective access by io.netty.util.internal.ReflectionUtil (file:/home/doom369/.m2/repository/io/netty/netty-common/4.1.16.Final/netty-common-4.1.16.Final.jar) to constructor java.nio.DirectByteBuffer(long,int)
WARNING: Illegal reflective access by io.netty.util.internal.ReflectionUtil (file:/home/doom369/.m2/repository/io/netty/netty-common/4.1.16.Final/netty-common-4.1.16.Final.jar) to method java.nio.Bits.unaligned()

Steps to reproduce

Run any netty server with Java 9.

Netty version

4.1.16.Final

JVM version (e.g. `java -version`)

java version "9"
Java(TM) SE Runtime Environment (build 9+181)
Java HotSpot(TM) 64-Bit Server VM (build 9+181, mixed mode)

Maybe it would be better to do not access above classes in case of java 9 to avoid warning?

Issue Analytics

State:
Created 6 years ago
Comments:20 (13 by maintainers)

Top GitHub Comments

23reactions

rockwotjcommented, Oct 5, 2017

Can we re-open this to actually solve the issue, I’d hate for things to break later on because this never got fixed?

The warning is quite clear this will break later on.

4reactions

dynawinkcommented, Oct 8, 2019

The error still occurs with netty 5.0.0.Alpha2. Please reopen the issue.

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