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Foreign Memory & FFM vs JNI

MemorySegment, Arena, downcalls and why FFM replaces most hand-written JNI.

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Confined arena example

Java
public class Example {
    public static void main(String[] args) {
        try (Arena arena = Arena.ofConfined()) {
                MemorySegment segment = arena.allocate(16);
                // invoke native function via linker
            }
    }
}

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Test yourself

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