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VM Options - IDEA​

At startup, you need to add VM Options parameters, otherwise an error will occur.

Exception in thread "main" java.lang.IllegalAccessError: class org.agrona.UnsafeApi (in unnamed module @0x6576fe71) cannot access class jdk.internal.misc.Unsafe (in module java.base) because module java.base does not export jdk.internal.misc to unnamed module
	at org.agrona.UnsafeApi.getUnsafe(UnsafeApi.java)
	at org.agrona.UnsafeApi.<clinit>(UnsafeApi.java)
	at org.agrona.BufferUtil.<clinit>(BufferUtil.java:43)

Add VM Options parameters in the IDE

Edit Configurations step1

Add VM options step1

step1

VM options parameters

--add-opens java.base/jdk.internal.misc=ALL-UNNAMED
--enable-native-access=ALL-UNNAMED

step1

Run step1

VM Options - JAR​

When starting a jar, you need to add VM Options parameters, otherwise an error will occur.

java \
--add-opens java.base/jdk.internal.misc=ALL-UNNAMED \
--enable-native-access=ALL-UNNAMED \
-jar target/ionet-quick-demo.jar

Why VM Options Are Required​

These parameters allow Aeron to use the Unsafe API for high-performance off-heap memory operations.

Aeron is a system focused on zero-copy and low latency. Internally, it uses Java's Unsafe class for direct memory operations (such as off-heap memory/direct buffers), to avoid GC impact and improve data processing speed.

--add-opens java.base/jdk.internal.misc=ALL-UNNAMED
--enable-native-access=ALL-UNNAMED