From github.com+318788+s1ck at openjdk.java.net  Wed Apr 14 00:20:19 2021
From: github.com+318788+s1ck at openjdk.java.net (Martin Junghanns)
Date: Wed, 14 Apr 2021 00:20:19 GMT
Subject: RFR: Bring back support for GPR visitors
Message-ID: <p13NEXpIKDqi6IV-iCUb23VW4Q2qWir0sGYF6Dli6Dc=.952bbcc8-72d3-40db-9cef-b3a4361a4cbd@github.com>

Hey @shipilev First of all: Thanks for this useful library. I wanted to switch from jol 0.10 to 0.15 in one of my projects because of some issues on openJDK 15. I discovered that the ability to register visitors had been removed at some point. The interface `org.openjdk.jol.info.GraphVisitor` is actually still around. I find that feature quite useful as it allows users to compute some custom statistics of the object graph. I tried to use the `GraphLayout` to access the GPRs, but it's all package-private.

It would be nice if we could bring the feature back. Also, if you think the approach is not ideal, we can maybe figure out something else.

Thanks for your time.

-------------

Commit messages:
 - Bring back support for GPR visitors

Changes: https://git.openjdk.java.net/jol/pull/15/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jol&pr=15&range=00
  Stats: 22 lines in 4 files changed: 16 ins; 0 del; 6 mod
  Patch: https://git.openjdk.java.net/jol/pull/15.diff
  Fetch: git fetch https://git.openjdk.java.net/jol pull/15/head:pull/15

PR: https://git.openjdk.java.net/jol/pull/15

From github.com+415502+stokito at openjdk.java.net  Wed Apr 14 05:55:04 2021
From: github.com+415502+stokito at openjdk.java.net (Sergey Ponomarev)
Date: Wed, 14 Apr 2021 05:55:04 GMT
Subject: RFR: Bring back support for GPR visitors
In-Reply-To: <p13NEXpIKDqi6IV-iCUb23VW4Q2qWir0sGYF6Dli6Dc=.952bbcc8-72d3-40db-9cef-b3a4361a4cbd@github.com>
References: <p13NEXpIKDqi6IV-iCUb23VW4Q2qWir0sGYF6Dli6Dc=.952bbcc8-72d3-40db-9cef-b3a4361a4cbd@github.com>
Message-ID: <aNRyKy3hJbjJp1YAHgwD2ptGWA-lZGnpgpoTfgHxJfE=.86063ff6-f375-4e11-a4b9-5b9a9409defc@github.com>

On Mon, 12 Apr 2021 16:00:49 GMT, Martin Junghanns <github.com+318788+s1ck at openjdk.org> wrote:

> Hey @shipilev First of all: Thanks for this useful library. I wanted to switch from jol 0.10 to 0.15 in one of my projects because of some issues on openJDK 15. I discovered that the ability to register visitors had been removed at some point. The interface `org.openjdk.jol.info.GraphVisitor` is actually still around. I find that feature quite useful as it allows users to compute some custom statistics of the object graph. I tried to use the `GraphLayout` to access the GPRs, but it's all package-private.
> 
> It would be nice if we could bring the feature back. Also, if you think the approach is not ideal, we can maybe figure out something else.
> 
> Thanks for your time.

Marked as reviewed by stokito at github.com (no known OpenJDK username).

-------------

PR: https://git.openjdk.java.net/jol/pull/15

From orionllmain at gmail.com  Sat Apr 17 11:19:30 2021
From: orionllmain at gmail.com (Zheka Kozlov)
Date: Sat, 17 Apr 2021 18:19:30 +0700
Subject: JOL is broken on module path
Message-ID: <CAF2POUda0Ye3+w=XXMfcoarUgP2UPnyOWqjQCDoSRR2tuniRPg@mail.gmail.com>

Hi!

javac cannot compile a Java project with module-info.java that requires JOL:

module <module> {
    requires jol.core;
}

Error: the unnamed module reads package java.lang from both java.base and
jol.core

The problem is the class JOLUnsafeTrampoline which is in the java.lang
package. This causes a split package error.

I propose the following simple solution. Since the class is injected via
Unsafe::defineAnonymousClass, we can put it anywhere in the JAR. For
example, we can put it in the root without the .class extension (so Java
will not treat it as a class file).

What do you think?

From github.com+318788+s1ck at openjdk.java.net  Tue Apr 20 14:25:16 2021
From: github.com+318788+s1ck at openjdk.java.net (Martin Junghanns)
Date: Tue, 20 Apr 2021 14:25:16 GMT
Subject: RFR: Bring back support for GPR visitors
In-Reply-To: <aNRyKy3hJbjJp1YAHgwD2ptGWA-lZGnpgpoTfgHxJfE=.86063ff6-f375-4e11-a4b9-5b9a9409defc@github.com>
References: <p13NEXpIKDqi6IV-iCUb23VW4Q2qWir0sGYF6Dli6Dc=.952bbcc8-72d3-40db-9cef-b3a4361a4cbd@github.com>
 <aNRyKy3hJbjJp1YAHgwD2ptGWA-lZGnpgpoTfgHxJfE=.86063ff6-f375-4e11-a4b9-5b9a9409defc@github.com>
Message-ID: <7N3DIjezMMASvKGJf89K-0JrCy-aCJiFI75xcQqkTyo=.71e29122-7a36-48fb-88c9-9e12d2dedb75@github.com>

On Wed, 14 Apr 2021 05:51:54 GMT, Sergey Ponomarev <github.com+415502+stokito at openjdk.org> wrote:

>> Hey @shipilev First of all: Thanks for this useful library. I wanted to switch from jol 0.10 to 0.15 in one of my projects because of some issues on openJDK 15. I discovered that the ability to register visitors had been removed at some point. The interface `org.openjdk.jol.info.GraphVisitor` is actually still around. I find that feature quite useful as it allows users to compute some custom statistics of the object graph. I tried to use the `GraphLayout` to access the GPRs, but it's all package-private.
>> 
>> It would be nice if we could bring the feature back. Also, if you think the approach is not ideal, we can maybe figure out something else.
>> 
>> Thanks for your time.
>
> Marked as reviewed by stokito at github.com (no known OpenJDK username).

@stokito Thanks for the review! What are the next steps to get this merged / released?

-------------

PR: https://git.openjdk.java.net/jol/pull/15

From github.com+415502+stokito at openjdk.java.net  Tue Apr 20 14:30:13 2021
From: github.com+415502+stokito at openjdk.java.net (Sergey Ponomarev)
Date: Tue, 20 Apr 2021 14:30:13 GMT
Subject: RFR: Bring back support for GPR visitors
In-Reply-To: <p13NEXpIKDqi6IV-iCUb23VW4Q2qWir0sGYF6Dli6Dc=.952bbcc8-72d3-40db-9cef-b3a4361a4cbd@github.com>
References: <p13NEXpIKDqi6IV-iCUb23VW4Q2qWir0sGYF6Dli6Dc=.952bbcc8-72d3-40db-9cef-b3a4361a4cbd@github.com>
Message-ID: <0W9103oDsa8sNC6k75STCoRAMrG7vflbWWxU1ypNh1E=.f50cb284-85a9-49d5-afcc-8a19d0e45d85@github.com>

On Mon, 12 Apr 2021 16:00:49 GMT, Martin Junghanns <github.com+318788+s1ck at openjdk.org> wrote:

> Hey @shipilev First of all: Thanks for this useful library. I wanted to switch from jol 0.10 to 0.15 in one of my projects because of some issues on openJDK 15. I discovered that the ability to register visitors had been removed at some point. The interface `org.openjdk.jol.info.GraphVisitor` is actually still around. I find that feature quite useful as it allows users to compute some custom statistics of the object graph. I tried to use the `GraphLayout` to access the GPRs, but it's all package-private.
> 
> It would be nice if we could bring the feature back. Also, if you think the approach is not ideal, we can maybe figure out something else.
> 
> Thanks for your time.

You have to sign OCA as the bot said you. Then wait while Alexey reviews the PR

-------------

PR: https://git.openjdk.java.net/jol/pull/15

From github.com+318788+s1ck at openjdk.java.net  Tue Apr 20 14:30:13 2021
From: github.com+318788+s1ck at openjdk.java.net (Martin Junghanns)
Date: Tue, 20 Apr 2021 14:30:13 GMT
Subject: RFR: Bring back support for GPR visitors
In-Reply-To: <p13NEXpIKDqi6IV-iCUb23VW4Q2qWir0sGYF6Dli6Dc=.952bbcc8-72d3-40db-9cef-b3a4361a4cbd@github.com>
References: <p13NEXpIKDqi6IV-iCUb23VW4Q2qWir0sGYF6Dli6Dc=.952bbcc8-72d3-40db-9cef-b3a4361a4cbd@github.com>
Message-ID: <767lu0mtcVXwwZhocav1r29m2jBvh-8Io0Rr7lzWPK0=.73cbd85e-ae6f-4e6a-8a2b-28ebcf24a18a@github.com>

On Mon, 12 Apr 2021 16:00:49 GMT, Martin Junghanns <github.com+318788+s1ck at openjdk.org> wrote:

> Hey @shipilev First of all: Thanks for this useful library. I wanted to switch from jol 0.10 to 0.15 in one of my projects because of some issues on openJDK 15. I discovered that the ability to register visitors had been removed at some point. The interface `org.openjdk.jol.info.GraphVisitor` is actually still around. I find that feature quite useful as it allows users to compute some custom statistics of the object graph. I tried to use the `GraphLayout` to access the GPRs, but it's all package-private.
> 
> It would be nice if we could bring the feature back. Also, if you think the approach is not ideal, we can maybe figure out something else.
> 
> Thanks for your time.

Thanks. I did already sign the OCA. Let's wait then :)

-------------

PR: https://git.openjdk.java.net/jol/pull/15