From axeld at pinc-software.de  Thu Sep 27 15:23:42 2018
From: axeld at pinc-software.de (=?UTF-8?Q?Axel_D=c3=b6rfler?=)
Date: Thu, 27 Sep 2018 17:23:42 +0200
Subject: Extending a Java class
Message-ID: <67ff4397-ab78-12c1-bde1-73b8af623b06@pinc-software.de>

Hi there,

I'm trying to extend an Abstract java base class, and add a new method 
to it. However, that doesn't seem to work.

I've tried it like this:

var object = Java.extend(MyType, {
	newFunction: function(argument) {
		...
	}
});

And that:

MyType.newFunction = function(...) {...};
var object = new MyType;

And also:

var object = new MyType({
	newFunction: ...
});

While it will all happily accept those things, none of them worked.
When I try to call the method, it'll say:
TypeError: object.newFunction is not a function

Do you have any idea how I could solve this? Overriding an existing 
method works easily, adding a new method does not (at least not this way).

Kind regards,
    Axel D?rfler.

From sundararajan.athijegannathan at oracle.com  Fri Sep 28 09:34:41 2018
From: sundararajan.athijegannathan at oracle.com (Sundararajan Athijegannathan)
Date: Fri, 28 Sep 2018 15:04:41 +0530
Subject: Extending a Java class
In-Reply-To: <67ff4397-ab78-12c1-bde1-73b8af623b06@pinc-software.de>
References: <67ff4397-ab78-12c1-bde1-73b8af623b06@pinc-software.de>
Message-ID: <5BADF5B1.3090806@oracle.com>

It is hard to say what went wrong without looking at your full sample/test.

Openjdk wiki page explains Java.extend function is here:

https://wiki.openjdk.java.net/display/Nashorn/Nashorn%2Bextensions#Nashornextensions-java_extend

You may want to take a look at nashorn samples that use Java.extend such 
these ->

http://hg.openjdk.java.net/jdk/jdk/file/7bd8d6b011c9/src/sample/nashorn/flexijson.js
http://hg.openjdk.java.net/jdk/jdk/file/7bd8d6b011c9/src/sample/nashorn/resourcetrysuggester.js

Hope this helps,
-Sundar

On 27/09/18, 8:53 PM, Axel D?rfler wrote:
> Hi there,
>
> I'm trying to extend an Abstract java base class, and add a new method 
> to it. However, that doesn't seem to work.
>
> I've tried it like this:
>
> var object = Java.extend(MyType, {
>     newFunction: function(argument) {
>         ...
>     }
> });
>
> And that:
>
> MyType.newFunction = function(...) {...};
> var object = new MyType;
>
> And also:
>
> var object = new MyType({
>     newFunction: ...
> });
>
> While it will all happily accept those things, none of them worked.
> When I try to call the method, it'll say:
> TypeError: object.newFunction is not a function
>
> Do you have any idea how I could solve this? Overriding an existing 
> method works easily, adding a new method does not (at least not this 
> way).
>
> Kind regards,
>    Axel D?rfler.

From axeld at pinc-software.de  Fri Sep 28 09:49:11 2018
From: axeld at pinc-software.de (=?UTF-8?Q?Axel_D=c3=b6rfler?=)
Date: Fri, 28 Sep 2018 11:49:11 +0200
Subject: Extending a Java class
In-Reply-To: <5BADF5B1.3090806@oracle.com>
References: <67ff4397-ab78-12c1-bde1-73b8af623b06@pinc-software.de>
 <5BADF5B1.3090806@oracle.com>
Message-ID: <3236fc28-97fd-5a38-cc5d-ad5ec73203f2@pinc-software.de>

Am 28/09/2018 um 11:34 schrieb Sundararajan Athijegannathan:
> It is hard to say what went wrong without looking at your full sample/test.
> 
> Openjdk wiki page explains Java.extend function is here:
> http://hg.openjdk.java.net/jdk/jdk/file/7bd8d6b011c9/src/sample/nashorn/resourcetrysuggester.js 

Thanks! This usage suggests that it should actually work.

Here is my full example stripped down to the bare minimum:

----------------8<----------------
var MatcherEditor = 
Java.type("ca.odell.glazedlists.matchers.AbstractMatcherEditor");

var filter = new (Java.extend(MatcherEditor)) {
		setEnabled: function(enabled) {
			if (enabled) {
				fireMatchNone();
			} else {
				fireMatchAll();
			}
		}
	};
filter.setEnabled(true);
----------------8<----------------

The error is:
TypeError: filter.setEnabled is not a function in <eval> at line number 13

For the Glazedlists class used, see here:
http://static.javadoc.io/net.java.dev.glazedlists/glazedlists_java16/1.10.0/ca/odell/glazedlists/matchers/AbstractMatcherEditor.html

Source:
https://github.com/glazedlists/glazedlists/blob/master/core/src/main/java/ca/odell/glazedlists/matchers/AbstractMatcherEditor.java

That looks like a bug to me. But if there's a workaround, I'll take it :-)

Kind regards,
 ?? Axel D?rfler.