Event without arguments outputs Exception (compilation error)

WHen I try to compile this contract:

package io.neow3j.examples.contractdev.contracts;

import io.neow3j.devpack.annotations.DisplayName;
import io.neow3j.devpack.annotations.ManifestExtra;
import io.neow3j.devpack.events.Event;

@ManifestExtra(key = "name", value = "SingleArgumentContract")
@ManifestExtra(key = "author", value = "AxLabs")
public class SingleArgumentContract {

    @DisplayName("onEvent")
    static Event onEvent;

    public static boolean anything() throws Exception {
        onEvent.notify();
        return true;
    }
}

The output is:

Exception in thread "main" java.lang.IndexOutOfBoundsException
        at org.objectweb.asm.tree.InsnList.get(InsnList.java:94)
        at io.neow3j.compiler.NeoMethod.convert(NeoMethod.java:474)
        at io.neow3j.compiler.converters.MethodsConverter.handleUncachedMethodCall(MethodsConverter.java:183)
        at io.neow3j.compiler.converters.MethodsConverter.handleMethodCall(MethodsConverter.java:157)
        at io.neow3j.compiler.converters.MethodsConverter.handleInvoke(MethodsConverter.java:138)
        at io.neow3j.compiler.converters.MethodsConverter.convert(MethodsConverter.java:73)
        at io.neow3j.compiler.Compiler.handleInsn(Compiler.java:388)
        at io.neow3j.compiler.NeoMethod.convert(NeoMethod.java:476)
        at io.neow3j.compiler.Compiler.compileClass(Compiler.java:242)
        at io.neow3j.compiler.Compiler.compileClass(Compiler.java:214)
        at io.neow3j.examples.contractdev.CompileAndDeploy.main(CompileAndDeploy.java:41)

It seems that the problem is the Event.

So… if I change to Event2Args it works:

package io.neow3j.examples.contractdev.contracts;

import io.neow3j.devpack.annotations.DisplayName;
import io.neow3j.devpack.annotations.ManifestExtra;
import io.neow3j.devpack.events.Event;

@ManifestExtra(key = "name", value = "SingleArgumentContract")
@ManifestExtra(key = "author", value = "AxLabs")
public class SingleArgumentContract {

    @DisplayName("onEvent")
    static Event2Args<String, String> onEvent;

    public static boolean anything() throws Exception {
        onEvent.notify("test", "test");
        return true;
    }
}

But, if I try to compile the following (only using onEvent.notify() in a Event2Args type), it miserably fails:

package io.neow3j.examples.contractdev.contracts;

import io.neow3j.devpack.annotations.DisplayName;
import io.neow3j.devpack.annotations.ManifestExtra;
import io.neow3j.devpack.events.Event;

@ManifestExtra(key = "name", value = "SingleArgumentContract")
@ManifestExtra(key = "author", value = "AxLabs")
public class SingleArgumentContract {

    @DisplayName("onEvent")
    static Event2Args<String, String> onEvent;

    public static boolean anything() throws Exception {
        onEvent.notify();
        return true;
    }
}

In my opinion, the compiler should either not support the “Event” without parameters, or provide a better error message, or provide a way that the developer can use Event.

[csmuller]

😃 Good, then we’ll go with trigger() 👍

[csmuller]

😲 it’s the Object.notify() method you used there. I only see that name collision now 😒 That method is not intended to be used on events (or on anything in the devpack). But it looks like we need to find a different naming for the notify(...) methods to prevent this misunderstanding.