NPE in FieldSerializer

Troubleshooting
1

This simple test case produces a NPE with the master branch and in beta2. When I debug the class with Intellij it seems that savedCtors in FieldSerializer is null. But I can’t understand why because it should be initialized in this line:

private static Map<Class, Constructor> savedCtors = new HashMap<Class, Constructor>();

I’m very confused now.

import com.jme3.network.serializing.Serializer;
import com.jme3.network.serializing.serializers.FieldSerializer;

public class SerializerTest {
    static {
        Serializer.registerClass(Object.class, new FieldSerializer());
    }
    public static void main(String[] args) {}
}

Exception in thread "main" java.lang.ExceptionInInitializerError
	at com.jvpichowski.SerializerTest.<clinit>(SerializerTest.java:13)
	at java.lang.Class.forName0(Native Method)
	at java.lang.Class.forName(Class.java:264)
	at com.intellij.rt.execution.application.AppMain.main(AppMain.java:123)
Caused by: java.lang.NullPointerException
	at com.jme3.network.serializing.serializers.FieldSerializer.checkClass(FieldSerializer.java:62)
	at com.jme3.network.serializing.serializers.FieldSerializer.initialize(FieldSerializer.java:85)
	at com.jme3.network.serializing.Serializer.registerClassForId(Serializer.java:206)
	at com.jme3.network.serializing.Serializer.registerClass(Serializer.java:304)
	at com.jme3.network.serializing.Serializer.getSerializerRegistration(Serializer.java:361)
	at com.jme3.network.serializing.Serializer.getSerializer(Serializer.java:316)
	at com.jme3.network.serializing.Serializer.registerClass(Serializer.java:228)
	at com.jme3.network.serializing.Serializer.registerClass(Serializer.java:152)
	at com.jme3.network.serializing.Serializer.<clinit>(Serializer.java:138)
	... 4 more

Does this test fail with your setup and do you guys have any ideas?

2

It makes no sense to register a serializer for Object.class.

Edit: and I have no idea why you get an NPE. Funky bad Java-magic (maybe incremental compile bug?)… if the accessed class doesn’t have its static initializers initialized first. That’s bad.

Edit 2: try moving the registration line inside main().

3

I tried to make a very simple test case. I looked at your es-net example and there is this line which produces the same error:

 Serializer.registerClass(Name.class, new FieldSerializer());

My main goal is to get that example working. Do I have to register my components in this way?

Now I created a clean new project with BootMonnkey. It contains only this two classes:

public class Name {

    public String name;

    public Name(){
        name = "";
    }

    public Name(String name){
        this.name = name;
    }

    public String getName() {
        return name;
    }
}

and

import com.jme3.network.serializing.Serializer;
import com.jme3.network.serializing.serializers.FieldSerializer;

public class Main {

    public static void main( String... args ) {
        Serializer.registerClass(Name.class, new FieldSerializer());
    }
}

It sadly doesn’t work yet. Is there anything missing like an annotation in the Name class?

Edit: Or is it generally wrong how I try to register my components to the network?

4

That should work. I’m not sure why it isn’t.

If the examples are also failing then there is definitely something weird going on. Those all work fine for me.