Re: RFR: JDK-8044629: (reflect) Constructor.getAnnotatedReceiverType() returns wrong value

[Martin Buchholz]

I filed a couple of bugs.  Here's a relevant JIRA search:

https://bugs.openjdk.java.net/issues/?jql=Subcomponent%20%3D%20java.lang%3Areflect%20AND%20watcher%20%3D%20martin

Because of the trickiness of local vs inner classes, Alex may want to make
a decision on the correct behavior.


On Fri, Jul 22, 2016 at 6:11 PM, Martin Buchholz 
wrote:

> Bug 8029042: Receiver parameter not supported on local class constructor
> also suggests that a local class of an instance method "is a perfectly
> good inner class" and so getAnnotatedReceiverType should treat them
> equivalently.
>
> On Thu, Jul 21, 2016 at 11:50 AM, Joel Borggrén-Franck <
> joel.borggren.fra...@gmail.com> wrote:
>
>> This is the first time I noticed the second paragraph of $14.3, strange
>> indeed! I'd ping compiler-dev with this, Alex will probably know if this is
>> a spec bug in $14.3 or just an irregularity.
>>
>> Cheers
>> /Joel
>>
>> On Jul 21, 2016 20:39, "Martin Buchholz"  wrote:
>>
>>> Joel, Thanks for responding so quickly!
>>>
>>> Here' s a slightly modified version of my repro recipe:
>>> You can see that local classes in instance methods have a receiver type,
>>> just like a member inner class.
>>> local classes in static methods (naturally!) do not.  I expect the two
>>> flavors of local classes to be treated differently.
>>>
>>> I've never understood why
>>> """All local classes are inner classes"""
>>> (even in a static method?)
>>> https://docs.oracle.com/javase/specs/jls/se8/html/jls-14.html#jls-14.3
>>>
>>>
>>> import java.lang.reflect.Constructor;
>>>
>>> public class LocalClassReceiverTypeBug {
>>> public static void main(String[] args) throws Throwable {
>>> class StaticLocal {}
>>> printConstructor(StaticLocal.class);
>>> new LocalClassReceiverTypeBug().instanceMain();
>>> }
>>>
>>> public void instanceMain() throws Throwable {
>>> class InstanceLocal {}
>>> printConstructor(InstanceLocal.class);
>>> printConstructor(Inner.class);
>>> // printConstructor(Nested.class);
>>> }
>>>
>>> static class Nested {}
>>> class Inner {}
>>>
>>> static void printConstructor(Class klazz) {
>>> Constructor[] constructors = klazz.getDeclaredConstructors();
>>> if (constructors.length != 1) throw new AssertionError();
>>> Constructor constructor = constructors[0];
>>> System.out.printf("constructor=%s receivertype=%s%n",
>>>   constructor,
>>>   constructor.getAnnotatedReceiverType());
>>> }
>>> }
>>> ==> javac -source 9 -Xlint:all LocalClassReceiverTypeBug.java
>>> ==> java -esa -ea LocalClassReceiverTypeBug
>>> constructor=LocalClassReceiverTypeBug$1StaticLocal() receivertype=null
>>> constructor=LocalClassReceiverTypeBug$1InstanceLocal(LocalClassReceiverTypeBug)
>>> receivertype=null
>>> constructor=LocalClassReceiverTypeBug$Inner(LocalClassReceiverTypeBug)
>>> receivertype=sun.reflect.annotation.AnnotatedTypeFactory$AnnotatedTypeBaseImpl@1810399e
>>>
>>>
>>> On Thu, Jul 21, 2016 at 11:16 AM, Joel Borggrén-Franck <
>>> joel.borggren.fra...@gmail.com> wrote:
>>>
 Hi Martin,

 I'm away from my workstation at the moment, so this is from memory.
 IIRC a local class is pure scoping and lacks an "outer this" which is what
 you annotate for constructors. There should not be receiver type to
 annotate. Since I can't run your code I can't see what's wrong but I might
 be able to help if you paste the output from a run.

 Cheers
 /Joel

 On Jul 21, 2016 19:49, "Martin Buchholz"  wrote:

> Hi Joel, Paul,
>
> A coworker ran into the change of behavior here in jdk9.
> Specifically, we noticed that a local class constructor has a receiver
> parameter, but getAnnotatedReceiverType returns null.  The changed jdk9
> spec is actually very clear about that:
>
>
> http://download.java.net/java/jdk9/docs/api/java/lang/reflect/Constructor.html#getAnnotatedReceiverType--
> """If this Executable object represents a static method or represents
> a constructor of a top level, static member, local, or anonymous class,
> then the return value is null."""
>
> BUT we can't think of any reason WHY a local inner class would be
> treated differently from an inner member class.  Why not the simple and
> obvious rule: if there is a receiver parameter, return an appropriate
> non-null AnnotatedType?
>
> You already have an excellent jtreg test, but here's what I was
> playing with:
>
> import java.lang.reflect.Constructor;
>
> public class LocalClassReceiverTypeBug {
> public static void main(String[] args) throws Throwable {
> class StaticLocal {}
> printConstructor(StaticLocal.class);
> new LocalClassReceiverTypeBug().instanceMain();
> }
>

Re: RFR: JDK-8044629: (reflect) Constructor.getAnnotatedReceiverType() returns wrong value

[Martin Buchholz]

Bug 8029042: Receiver parameter not supported on local class constructor
also suggests that a local class of an instance method "is a perfectly good
inner class" and so getAnnotatedReceiverType should treat them
equivalently.

On Thu, Jul 21, 2016 at 11:50 AM, Joel Borggrén-Franck <
joel.borggren.fra...@gmail.com> wrote:

> This is the first time I noticed the second paragraph of $14.3, strange
> indeed! I'd ping compiler-dev with this, Alex will probably know if this is
> a spec bug in $14.3 or just an irregularity.
>
> Cheers
> /Joel
>
> On Jul 21, 2016 20:39, "Martin Buchholz"  wrote:
>
>> Joel, Thanks for responding so quickly!
>>
>> Here' s a slightly modified version of my repro recipe:
>> You can see that local classes in instance methods have a receiver type,
>> just like a member inner class.
>> local classes in static methods (naturally!) do not.  I expect the two
>> flavors of local classes to be treated differently.
>>
>> I've never understood why
>> """All local classes are inner classes"""
>> (even in a static method?)
>> https://docs.oracle.com/javase/specs/jls/se8/html/jls-14.html#jls-14.3
>>
>>
>> import java.lang.reflect.Constructor;
>>
>> public class LocalClassReceiverTypeBug {
>> public static void main(String[] args) throws Throwable {
>> class StaticLocal {}
>> printConstructor(StaticLocal.class);
>> new LocalClassReceiverTypeBug().instanceMain();
>> }
>>
>> public void instanceMain() throws Throwable {
>> class InstanceLocal {}
>> printConstructor(InstanceLocal.class);
>> printConstructor(Inner.class);
>> // printConstructor(Nested.class);
>> }
>>
>> static class Nested {}
>> class Inner {}
>>
>> static void printConstructor(Class klazz) {
>> Constructor[] constructors = klazz.getDeclaredConstructors();
>> if (constructors.length != 1) throw new AssertionError();
>> Constructor constructor = constructors[0];
>> System.out.printf("constructor=%s receivertype=%s%n",
>>   constructor,
>>   constructor.getAnnotatedReceiverType());
>> }
>> }
>> ==> javac -source 9 -Xlint:all LocalClassReceiverTypeBug.java
>> ==> java -esa -ea LocalClassReceiverTypeBug
>> constructor=LocalClassReceiverTypeBug$1StaticLocal() receivertype=null
>> constructor=LocalClassReceiverTypeBug$1InstanceLocal(LocalClassReceiverTypeBug)
>> receivertype=null
>> constructor=LocalClassReceiverTypeBug$Inner(LocalClassReceiverTypeBug)
>> receivertype=sun.reflect.annotation.AnnotatedTypeFactory$AnnotatedTypeBaseImpl@1810399e
>>
>>
>> On Thu, Jul 21, 2016 at 11:16 AM, Joel Borggrén-Franck <
>> joel.borggren.fra...@gmail.com> wrote:
>>
>>> Hi Martin,
>>>
>>> I'm away from my workstation at the moment, so this is from memory. IIRC
>>> a local class is pure scoping and lacks an "outer this" which is what you
>>> annotate for constructors. There should not be receiver type to annotate.
>>> Since I can't run your code I can't see what's wrong but I might be able to
>>> help if you paste the output from a run.
>>>
>>> Cheers
>>> /Joel
>>>
>>> On Jul 21, 2016 19:49, "Martin Buchholz"  wrote:
>>>
 Hi Joel, Paul,

 A coworker ran into the change of behavior here in jdk9.  Specifically,
 we noticed that a local class constructor has a receiver parameter,
 but getAnnotatedReceiverType returns null.  The changed jdk9 spec is
 actually very clear about that:


 http://download.java.net/java/jdk9/docs/api/java/lang/reflect/Constructor.html#getAnnotatedReceiverType--
 """If this Executable object represents a static method or represents a
 constructor of a top level, static member, local, or anonymous class, then
 the return value is null."""

 BUT we can't think of any reason WHY a local inner class would be
 treated differently from an inner member class.  Why not the simple and
 obvious rule: if there is a receiver parameter, return an appropriate
 non-null AnnotatedType?

 You already have an excellent jtreg test, but here's what I was playing
 with:

 import java.lang.reflect.Constructor;

 public class LocalClassReceiverTypeBug {
 public static void main(String[] args) throws Throwable {
 class StaticLocal {}
 printConstructor(StaticLocal.class);
 new LocalClassReceiverTypeBug().instanceMain();
 }

 public void instanceMain() throws Throwable {
 class InstanceLocal {}
 printConstructor(InstanceLocal.class);
 printConstructor(Inner.class);
 printConstructor(Nested.class);
 }

 static class Nested {}
 class Inner {}

 static void printConstructor(Class klazz) {
 Constructor[] constructors = klazz.getDeclaredConstructors();
 if (constructors.length != 1) throw new 

Re: RFR: JDK-8044629: (reflect) Constructor.getAnnotatedReceiverType() returns wrong value

[David Holmes]

On 22/07/2016 4:50 AM, Joel Borggrén-Franck wrote:

This is the first time I noticed the second paragraph of $14.3, strange
indeed! I'd ping compiler-dev with this, Alex will probably know if this is
a spec bug in $14.3 or just an irregularity.


It is an irregularity - for want of a better word. See:

https://docs.oracle.com/javase/specs/jls/se8/html/jls-8.html#jls-8.1.3

"An instance of an inner class I whose declaration occurs in a static 
context has no lexically enclosing instances. "


David
-


Cheers
/Joel

On Jul 21, 2016 20:39, "Martin Buchholz"  wrote:


Joel, Thanks for responding so quickly!

Here' s a slightly modified version of my repro recipe:
You can see that local classes in instance methods have a receiver type,
just like a member inner class.
local classes in static methods (naturally!) do not.  I expect the two
flavors of local classes to be treated differently.

I've never understood why
"""All local classes are inner classes"""
(even in a static method?)
https://docs.oracle.com/javase/specs/jls/se8/html/jls-14.html#jls-14.3


import java.lang.reflect.Constructor;

public class LocalClassReceiverTypeBug {
public static void main(String[] args) throws Throwable {
class StaticLocal {}
printConstructor(StaticLocal.class);
new LocalClassReceiverTypeBug().instanceMain();
}

public void instanceMain() throws Throwable {
class InstanceLocal {}
printConstructor(InstanceLocal.class);
printConstructor(Inner.class);
// printConstructor(Nested.class);
}

static class Nested {}
class Inner {}

static void printConstructor(Class klazz) {
Constructor[] constructors = klazz.getDeclaredConstructors();
if (constructors.length != 1) throw new AssertionError();
Constructor constructor = constructors[0];
System.out.printf("constructor=%s receivertype=%s%n",
  constructor,
  constructor.getAnnotatedReceiverType());
}
}
==> javac -source 9 -Xlint:all LocalClassReceiverTypeBug.java
==> java -esa -ea LocalClassReceiverTypeBug
constructor=LocalClassReceiverTypeBug$1StaticLocal() receivertype=null
constructor=LocalClassReceiverTypeBug$1InstanceLocal(LocalClassReceiverTypeBug)
receivertype=null
constructor=LocalClassReceiverTypeBug$Inner(LocalClassReceiverTypeBug)
receivertype=sun.reflect.annotation.AnnotatedTypeFactory$AnnotatedTypeBaseImpl@1810399e


On Thu, Jul 21, 2016 at 11:16 AM, Joel Borggrén-Franck <
joel.borggren.fra...@gmail.com> wrote:


Hi Martin,

I'm away from my workstation at the moment, so this is from memory. IIRC
a local class is pure scoping and lacks an "outer this" which is what you
annotate for constructors. There should not be receiver type to annotate.
Since I can't run your code I can't see what's wrong but I might be able to
help if you paste the output from a run.

Cheers
/Joel

On Jul 21, 2016 19:49, "Martin Buchholz"  wrote:


Hi Joel, Paul,

A coworker ran into the change of behavior here in jdk9.  Specifically,
we noticed that a local class constructor has a receiver parameter,
but getAnnotatedReceiverType returns null.  The changed jdk9 spec is
actually very clear about that:


http://download.java.net/java/jdk9/docs/api/java/lang/reflect/Constructor.html#getAnnotatedReceiverType--
"""If this Executable object represents a static method or represents a
constructor of a top level, static member, local, or anonymous class, then
the return value is null."""

BUT we can't think of any reason WHY a local inner class would be
treated differently from an inner member class.  Why not the simple and
obvious rule: if there is a receiver parameter, return an appropriate
non-null AnnotatedType?

You already have an excellent jtreg test, but here's what I was playing
with:

import java.lang.reflect.Constructor;

public class LocalClassReceiverTypeBug {
public static void main(String[] args) throws Throwable {
class StaticLocal {}
printConstructor(StaticLocal.class);
new LocalClassReceiverTypeBug().instanceMain();
}

public void instanceMain() throws Throwable {
class InstanceLocal {}
printConstructor(InstanceLocal.class);
printConstructor(Inner.class);
printConstructor(Nested.class);
}

static class Nested {}
class Inner {}

static void printConstructor(Class klazz) {
Constructor[] constructors = klazz.getDeclaredConstructors();
if (constructors.length != 1) throw new AssertionError();
System.out.printf("constructor=%s%n", constructors[0]);
System.out.printf("receiver type=%s%n",
  constructors[0].getAnnotatedReceiverType());
}
}



On Wed, Aug 13, 2014 at 1:54 AM, Joel Borggren-Franck <
joel.fra...@oracle.com> wrote:


Hi Paul,

On 2014-06-24, Paul Sandoz wrote:


On Jun 17, 2014, at 6:52 PM, Joel Borggrén-Franck <

Re: RFR: JDK-8044629: (reflect) Constructor.getAnnotatedReceiverType() returns wrong value

[Joel Borggrén-Franck]

This is the first time I noticed the second paragraph of $14.3, strange
indeed! I'd ping compiler-dev with this, Alex will probably know if this is
a spec bug in $14.3 or just an irregularity.

Cheers
/Joel

On Jul 21, 2016 20:39, "Martin Buchholz"  wrote:

> Joel, Thanks for responding so quickly!
>
> Here' s a slightly modified version of my repro recipe:
> You can see that local classes in instance methods have a receiver type,
> just like a member inner class.
> local classes in static methods (naturally!) do not.  I expect the two
> flavors of local classes to be treated differently.
>
> I've never understood why
> """All local classes are inner classes"""
> (even in a static method?)
> https://docs.oracle.com/javase/specs/jls/se8/html/jls-14.html#jls-14.3
>
>
> import java.lang.reflect.Constructor;
>
> public class LocalClassReceiverTypeBug {
> public static void main(String[] args) throws Throwable {
> class StaticLocal {}
> printConstructor(StaticLocal.class);
> new LocalClassReceiverTypeBug().instanceMain();
> }
>
> public void instanceMain() throws Throwable {
> class InstanceLocal {}
> printConstructor(InstanceLocal.class);
> printConstructor(Inner.class);
> // printConstructor(Nested.class);
> }
>
> static class Nested {}
> class Inner {}
>
> static void printConstructor(Class klazz) {
> Constructor[] constructors = klazz.getDeclaredConstructors();
> if (constructors.length != 1) throw new AssertionError();
> Constructor constructor = constructors[0];
> System.out.printf("constructor=%s receivertype=%s%n",
>   constructor,
>   constructor.getAnnotatedReceiverType());
> }
> }
> ==> javac -source 9 -Xlint:all LocalClassReceiverTypeBug.java
> ==> java -esa -ea LocalClassReceiverTypeBug
> constructor=LocalClassReceiverTypeBug$1StaticLocal() receivertype=null
> constructor=LocalClassReceiverTypeBug$1InstanceLocal(LocalClassReceiverTypeBug)
> receivertype=null
> constructor=LocalClassReceiverTypeBug$Inner(LocalClassReceiverTypeBug)
> receivertype=sun.reflect.annotation.AnnotatedTypeFactory$AnnotatedTypeBaseImpl@1810399e
>
>
> On Thu, Jul 21, 2016 at 11:16 AM, Joel Borggrén-Franck <
> joel.borggren.fra...@gmail.com> wrote:
>
>> Hi Martin,
>>
>> I'm away from my workstation at the moment, so this is from memory. IIRC
>> a local class is pure scoping and lacks an "outer this" which is what you
>> annotate for constructors. There should not be receiver type to annotate.
>> Since I can't run your code I can't see what's wrong but I might be able to
>> help if you paste the output from a run.
>>
>> Cheers
>> /Joel
>>
>> On Jul 21, 2016 19:49, "Martin Buchholz"  wrote:
>>
>>> Hi Joel, Paul,
>>>
>>> A coworker ran into the change of behavior here in jdk9.  Specifically,
>>> we noticed that a local class constructor has a receiver parameter,
>>> but getAnnotatedReceiverType returns null.  The changed jdk9 spec is
>>> actually very clear about that:
>>>
>>>
>>> http://download.java.net/java/jdk9/docs/api/java/lang/reflect/Constructor.html#getAnnotatedReceiverType--
>>> """If this Executable object represents a static method or represents a
>>> constructor of a top level, static member, local, or anonymous class, then
>>> the return value is null."""
>>>
>>> BUT we can't think of any reason WHY a local inner class would be
>>> treated differently from an inner member class.  Why not the simple and
>>> obvious rule: if there is a receiver parameter, return an appropriate
>>> non-null AnnotatedType?
>>>
>>> You already have an excellent jtreg test, but here's what I was playing
>>> with:
>>>
>>> import java.lang.reflect.Constructor;
>>>
>>> public class LocalClassReceiverTypeBug {
>>> public static void main(String[] args) throws Throwable {
>>> class StaticLocal {}
>>> printConstructor(StaticLocal.class);
>>> new LocalClassReceiverTypeBug().instanceMain();
>>> }
>>>
>>> public void instanceMain() throws Throwable {
>>> class InstanceLocal {}
>>> printConstructor(InstanceLocal.class);
>>> printConstructor(Inner.class);
>>> printConstructor(Nested.class);
>>> }
>>>
>>> static class Nested {}
>>> class Inner {}
>>>
>>> static void printConstructor(Class klazz) {
>>> Constructor[] constructors = klazz.getDeclaredConstructors();
>>> if (constructors.length != 1) throw new AssertionError();
>>> System.out.printf("constructor=%s%n", constructors[0]);
>>> System.out.printf("receiver type=%s%n",
>>>   constructors[0].getAnnotatedReceiverType());
>>> }
>>> }
>>>
>>>
>>>
>>> On Wed, Aug 13, 2014 at 1:54 AM, Joel Borggren-Franck <
>>> joel.fra...@oracle.com> wrote:
>>>
 Hi Paul,

 On 2014-06-24, Paul Sandoz wrote:
 >
 > On Jun 17, 2014, at 6:52 PM, Joel 

Re: RFR: JDK-8044629: (reflect) Constructor.getAnnotatedReceiverType() returns wrong value

[Martin Buchholz]

Joel, Thanks for responding so quickly!

Here' s a slightly modified version of my repro recipe:
You can see that local classes in instance methods have a receiver type,
just like a member inner class.
local classes in static methods (naturally!) do not.  I expect the two
flavors of local classes to be treated differently.

I've never understood why
"""All local classes are inner classes"""
(even in a static method?)
https://docs.oracle.com/javase/specs/jls/se8/html/jls-14.html#jls-14.3


import java.lang.reflect.Constructor;

public class LocalClassReceiverTypeBug {
public static void main(String[] args) throws Throwable {
class StaticLocal {}
printConstructor(StaticLocal.class);
new LocalClassReceiverTypeBug().instanceMain();
}

public void instanceMain() throws Throwable {
class InstanceLocal {}
printConstructor(InstanceLocal.class);
printConstructor(Inner.class);
// printConstructor(Nested.class);
}

static class Nested {}
class Inner {}

static void printConstructor(Class klazz) {
Constructor[] constructors = klazz.getDeclaredConstructors();
if (constructors.length != 1) throw new AssertionError();
Constructor constructor = constructors[0];
System.out.printf("constructor=%s receivertype=%s%n",
  constructor,
  constructor.getAnnotatedReceiverType());
}
}
==> javac -source 9 -Xlint:all LocalClassReceiverTypeBug.java
==> java -esa -ea LocalClassReceiverTypeBug
constructor=LocalClassReceiverTypeBug$1StaticLocal() receivertype=null
constructor=LocalClassReceiverTypeBug$1InstanceLocal(LocalClassReceiverTypeBug)
receivertype=null
constructor=LocalClassReceiverTypeBug$Inner(LocalClassReceiverTypeBug)
receivertype=sun.reflect.annotation.AnnotatedTypeFactory$AnnotatedTypeBaseImpl@1810399e


On Thu, Jul 21, 2016 at 11:16 AM, Joel Borggrén-Franck <
joel.borggren.fra...@gmail.com> wrote:

> Hi Martin,
>
> I'm away from my workstation at the moment, so this is from memory. IIRC a
> local class is pure scoping and lacks an "outer this" which is what you
> annotate for constructors. There should not be receiver type to annotate.
> Since I can't run your code I can't see what's wrong but I might be able to
> help if you paste the output from a run.
>
> Cheers
> /Joel
>
> On Jul 21, 2016 19:49, "Martin Buchholz"  wrote:
>
>> Hi Joel, Paul,
>>
>> A coworker ran into the change of behavior here in jdk9.  Specifically,
>> we noticed that a local class constructor has a receiver parameter,
>> but getAnnotatedReceiverType returns null.  The changed jdk9 spec is
>> actually very clear about that:
>>
>>
>> http://download.java.net/java/jdk9/docs/api/java/lang/reflect/Constructor.html#getAnnotatedReceiverType--
>> """If this Executable object represents a static method or represents a
>> constructor of a top level, static member, local, or anonymous class, then
>> the return value is null."""
>>
>> BUT we can't think of any reason WHY a local inner class would be treated
>> differently from an inner member class.  Why not the simple and obvious
>> rule: if there is a receiver parameter, return an appropriate non-null
>> AnnotatedType?
>>
>> You already have an excellent jtreg test, but here's what I was playing
>> with:
>>
>> import java.lang.reflect.Constructor;
>>
>> public class LocalClassReceiverTypeBug {
>> public static void main(String[] args) throws Throwable {
>> class StaticLocal {}
>> printConstructor(StaticLocal.class);
>> new LocalClassReceiverTypeBug().instanceMain();
>> }
>>
>> public void instanceMain() throws Throwable {
>> class InstanceLocal {}
>> printConstructor(InstanceLocal.class);
>> printConstructor(Inner.class);
>> printConstructor(Nested.class);
>> }
>>
>> static class Nested {}
>> class Inner {}
>>
>> static void printConstructor(Class klazz) {
>> Constructor[] constructors = klazz.getDeclaredConstructors();
>> if (constructors.length != 1) throw new AssertionError();
>> System.out.printf("constructor=%s%n", constructors[0]);
>> System.out.printf("receiver type=%s%n",
>>   constructors[0].getAnnotatedReceiverType());
>> }
>> }
>>
>>
>>
>> On Wed, Aug 13, 2014 at 1:54 AM, Joel Borggren-Franck <
>> joel.fra...@oracle.com> wrote:
>>
>>> Hi Paul,
>>>
>>> On 2014-06-24, Paul Sandoz wrote:
>>> >
>>> > On Jun 17, 2014, at 6:52 PM, Joel Borggrén-Franck <
>>> joel.fra...@oracle.com> wrote:
>>> > >
>>> > > Can I get a review for this fix and javadoc clarification for
>>> https://bugs.openjdk.java.net/browse/JDK-8044629
>>> > >
>>> >
>>> > +1
>>> >
>>> > I never quite realised just how convoluted it was to determine that a
>>> class is an inner class.
>>>
>>> Neither did I until I had to implement it :)
>>>
>>> cheers
>>> /Joel
>>>
>>
>>

Re: RFR: JDK-8044629: (reflect) Constructor.getAnnotatedReceiverType() returns wrong value

[Joel Borggrén-Franck]

Hi Martin,

I'm away from my workstation at the moment, so this is from memory. IIRC a
local class is pure scoping and lacks an "outer this" which is what you
annotate for constructors. There should not be receiver type to annotate.
Since I can't run your code I can't see what's wrong but I might be able to
help if you paste the output from a run.

Cheers
/Joel

On Jul 21, 2016 19:49, "Martin Buchholz"  wrote:

> Hi Joel, Paul,
>
> A coworker ran into the change of behavior here in jdk9.  Specifically, we
> noticed that a local class constructor has a receiver parameter,
> but getAnnotatedReceiverType returns null.  The changed jdk9 spec is
> actually very clear about that:
>
>
> http://download.java.net/java/jdk9/docs/api/java/lang/reflect/Constructor.html#getAnnotatedReceiverType--
> """If this Executable object represents a static method or represents a
> constructor of a top level, static member, local, or anonymous class, then
> the return value is null."""
>
> BUT we can't think of any reason WHY a local inner class would be treated
> differently from an inner member class.  Why not the simple and obvious
> rule: if there is a receiver parameter, return an appropriate non-null
> AnnotatedType?
>
> You already have an excellent jtreg test, but here's what I was playing
> with:
>
> import java.lang.reflect.Constructor;
>
> public class LocalClassReceiverTypeBug {
> public static void main(String[] args) throws Throwable {
> class StaticLocal {}
> printConstructor(StaticLocal.class);
> new LocalClassReceiverTypeBug().instanceMain();
> }
>
> public void instanceMain() throws Throwable {
> class InstanceLocal {}
> printConstructor(InstanceLocal.class);
> printConstructor(Inner.class);
> printConstructor(Nested.class);
> }
>
> static class Nested {}
> class Inner {}
>
> static void printConstructor(Class klazz) {
> Constructor[] constructors = klazz.getDeclaredConstructors();
> if (constructors.length != 1) throw new AssertionError();
> System.out.printf("constructor=%s%n", constructors[0]);
> System.out.printf("receiver type=%s%n",
>   constructors[0].getAnnotatedReceiverType());
> }
> }
>
>
>
> On Wed, Aug 13, 2014 at 1:54 AM, Joel Borggren-Franck <
> joel.fra...@oracle.com> wrote:
>
>> Hi Paul,
>>
>> On 2014-06-24, Paul Sandoz wrote:
>> >
>> > On Jun 17, 2014, at 6:52 PM, Joel Borggrén-Franck <
>> joel.fra...@oracle.com> wrote:
>> > >
>> > > Can I get a review for this fix and javadoc clarification for
>> https://bugs.openjdk.java.net/browse/JDK-8044629
>> > >
>> >
>> > +1
>> >
>> > I never quite realised just how convoluted it was to determine that a
>> class is an inner class.
>>
>> Neither did I until I had to implement it :)
>>
>> cheers
>> /Joel
>>
>
>

Re: RFR: JDK-8044629: (reflect) Constructor.getAnnotatedReceiverType() returns wrong value

[Martin Buchholz]

Hi Joel, Paul,

A coworker ran into the change of behavior here in jdk9.  Specifically, we
noticed that a local class constructor has a receiver parameter,
but getAnnotatedReceiverType returns null.  The changed jdk9 spec is
actually very clear about that:

http://download.java.net/java/jdk9/docs/api/java/lang/reflect/Constructor.html#getAnnotatedReceiverType--
"""If this Executable object represents a static method or represents a
constructor of a top level, static member, local, or anonymous class, then
the return value is null."""

BUT we can't think of any reason WHY a local inner class would be treated
differently from an inner member class.  Why not the simple and obvious
rule: if there is a receiver parameter, return an appropriate non-null
AnnotatedType?

You already have an excellent jtreg test, but here's what I was playing
with:

import java.lang.reflect.Constructor;

public class LocalClassReceiverTypeBug {
public static void main(String[] args) throws Throwable {
class StaticLocal {}
printConstructor(StaticLocal.class);
new LocalClassReceiverTypeBug().instanceMain();
}

public void instanceMain() throws Throwable {
class InstanceLocal {}
printConstructor(InstanceLocal.class);
printConstructor(Inner.class);
printConstructor(Nested.class);
}

static class Nested {}
class Inner {}

static void printConstructor(Class klazz) {
Constructor[] constructors = klazz.getDeclaredConstructors();
if (constructors.length != 1) throw new AssertionError();
System.out.printf("constructor=%s%n", constructors[0]);
System.out.printf("receiver type=%s%n",
  constructors[0].getAnnotatedReceiverType());
}
}



On Wed, Aug 13, 2014 at 1:54 AM, Joel Borggren-Franck <
joel.fra...@oracle.com> wrote:

> Hi Paul,
>
> On 2014-06-24, Paul Sandoz wrote:
> >
> > On Jun 17, 2014, at 6:52 PM, Joel Borggrén-Franck <
> joel.fra...@oracle.com> wrote:
> > >
> > > Can I get a review for this fix and javadoc clarification for
> https://bugs.openjdk.java.net/browse/JDK-8044629
> > >
> >
> > +1
> >
> > I never quite realised just how convoluted it was to determine that a
> class is an inner class.
>
> Neither did I until I had to implement it :)
>
> cheers
> /Joel
>

Re: RFR: JDK-8044629: (reflect) Constructor.getAnnotatedReceiverType() returns wrong value

[Joel Borggren-Franck]

Hi Paul,

On 2014-06-24, Paul Sandoz wrote:
 
 On Jun 17, 2014, at 6:52 PM, Joel Borggrén-Franck joel.fra...@oracle.com 
 wrote:
  
  Can I get a review for this fix and javadoc clarification for 
  https://bugs.openjdk.java.net/browse/JDK-8044629
  
 
 +1
 
 I never quite realised just how convoluted it was to determine that a class 
 is an inner class.

Neither did I until I had to implement it :)

cheers
/Joel

Re: RFR: JDK-8044629: (reflect) Constructor.getAnnotatedReceiverType() returns wrong value

[Paul Sandoz]

On Jun 17, 2014, at 6:52 PM, Joel Borggrén-Franck joel.fra...@oracle.com 
wrote:

 Hi,
 
 Can I get a review for this fix and javadoc clarification for 
 https://bugs.openjdk.java.net/browse/JDK-8044629
 
 The problem is with potentially annotated receiver parameters, they only 
 exist for inner class constructors, so this fix makes sure that a ctor is for 
 an inner class or returns null (as for a static method) otherwise.
 
 CCC has been approved.
 
 Webrev: http://cr.openjdk.java.net/~jfranck/8044629/webrev.00/
 

+1

I never quite realised just how convoluted it was to determine that a class is 
an inner class.

Paul.