Use Method.getParameterCount() where possible

[Claes Redestad]

Thanks, pushed as https://bugs.openjdk.java.net/browse/JDK-8242208

/Claes

On 2020-04-06 13:38, Chris Hegarty wrote:
> The changes look good to me.
> 
> -Chris.
> 
>> On 6 Apr 2020, at 11:44, Claes Redestad <claes.redestad at oracle.com> wrote:
>>
>> Hi,
>>
>> looks good and trivial to me. I'll sponsor.
>>
>> /Claes
>>
>> (I hope we can wrap up https://bugs.openjdk.java.net/browse/JDK-8029019
>> some day, soon)
>>
>> On 2020-04-03 12:19, Christoph Dreis wrote:
>>> Hi,
>>> I noticed that the JDK itself still uses Method.getParameterTypes().length in a couple of places.
>>> This could be replaced with Method.getParameterCount() to avoid unnecessary cloning overhead.
>>> While this is often optimized away, I guess it's still good to not rely on that. Additionally, it's a little more concise to read.
>>> If you think this is worthwhile, I would need someone to sponsor that tiny change.
>>> P.S.: There is another occurrence in ForkJoinTask where I wasn't sure if I should change that, because it's usually changed under the JSR166 umbrella afaik.
>>> Cheers,
>>> Christoph
>>> ==== PATCH ====
>>> diff --git a/src/java.base/share/classes/java/lang/invoke/MethodHandleProxies.java b/src/java.base/share/classes/java/lang/invoke/MethodHandleProxies.java
>>> --- a/src/java.base/share/classes/java/lang/invoke/MethodHandleProxies.java
>>> +++ b/src/java.base/share/classes/java/lang/invoke/MethodHandleProxies.java
>>> @@ -276,13 +276,13 @@
>>>           switch (m.getName()) {
>>>           case "toString":
>>>               return (m.getReturnType() == String.class
>>> -                    && m.getParameterTypes().length == 0);
>>> +                    && m.getParameterCount() == 0);
>>>           case "hashCode":
>>>               return (m.getReturnType() == int.class
>>> -                    && m.getParameterTypes().length == 0);
>>> +                    && m.getParameterCount() == 0);
>>>           case "equals":
>>>               return (m.getReturnType() == boolean.class
>>> -                    && m.getParameterTypes().length == 1
>>> +                    && m.getParameterCount() == 1
>>>                       && m.getParameterTypes()[0] == Object.class);
>>>           }
>>>           return false;
>>> diff --git a/src/java.base/share/classes/java/lang/reflect/Executable.java b/src/java.base/share/classes/java/lang/reflect/Executable.java
>>> --- a/src/java.base/share/classes/java/lang/reflect/Executable.java
>>> +++ b/src/java.base/share/classes/java/lang/reflect/Executable.java
>>> @@ -378,7 +378,7 @@
>>>       private void verifyParameters(final Parameter[] parameters) {
>>>           final int mask = Modifier.FINAL | Modifier.SYNTHETIC | Modifier.MANDATED;
>>> -        if (getParameterTypes().length != parameters.length)
>>> +        if (getParameterCount() != parameters.length)
>>>               throw new MalformedParametersException("Wrong number of parameters in MethodParameters attribute");
>>>           for (Parameter parameter : parameters) {
>>> diff --git a/src/java.base/share/classes/sun/reflect/annotation/AnnotationType.java b/src/java.base/share/classes/sun/reflect/annotation/AnnotationType.java
>>> --- a/src/java.base/share/classes/sun/reflect/annotation/AnnotationType.java
>>> +++ b/src/java.base/share/classes/sun/reflect/annotation/AnnotationType.java
>>> @@ -121,7 +121,7 @@
>>>               if (Modifier.isPublic(method.getModifiers()) &&
>>>                   Modifier.isAbstract(method.getModifiers()) &&
>>>                   !method.isSynthetic()) {
>>> -                if (method.getParameterTypes().length != 0) {
>>> +                if (method.getParameterCount() != 0) {
>>>                       throw new IllegalArgumentException(method + " has params");
>>>                   }
>>>                   String name = method.getName();
>