Hi Joel,
> IIRC name isn’t actually interned with String.intern() but in the VM:s Symbol
> table as a name representing a (Java) method. Should be equivalent, as long
> as we don’t start comparing it with == with interned Strings.
I think that's not true.
The following small test program prints true on the console:
public class Test {
public static void main(String... argv) throws Exception {
Method m = Test.class.getMethod("main", String[].class);
System.out.println(m.getName() == new String("main").intern());
}
}
And if you look into reflection.cpp at lines 787-789, you will see following
code:
Symbol* method_name = method->name();
oop name_oop = StringTable::intern(method_name, CHECK_NULL);
Handle name = Handle(THREAD, name_oop);
And later at the line 798 we have this code:
java_lang_reflect_Method::set_name(mh(), name());
Therefore I would say the name is actually interned in terms of String.intern().
And you can compare the name of a method with == with interned Strings.
The same applies to a name of a class and to a name of a field too.
Please feel free to correct me.
Best regards,
Andrej Golovnin
>
> cheers
> /Joel
>
> On 07 Jun 2014, at 22:34, Andrej Golovnin <andrej.golov...@gmail.com> wrote:
>
>> Hi Joe,
>>
>>> Sorry for the belated review.
>>>
>>> Generally the change looks good. One question, in
>>>
>>> 2803 private boolean matchesNameAndDescriptor(Method m1, Method m2)
>>> {
>>> 2804 return m1.getReturnType() == m2.getReturnType() &&
>>> 2805 m1.getName() == m2.getName() &&
>>> 2806 arrayContentsEq(m1.getParameterTypes(),
>>> 2807 m2.getParameterTypes());
>>> 2808 }
>>>
>>> Should the equality check on 2805 be .equals rather than == ?
>>>
>>
>> "==" can be used in this case as the method name is interned by JVM.
>> Here is the comment for the field "name" from java.lang.reflect.Method:
>>
>> // This is guaranteed to be interned by the VM in the 1.4
>> // reflection implementation
>> private String name;
>>
>> BTW, in the old version of Class in the line 2766 there was already a
>> similar check:
>>
>> 2764 if (m != null &&
>> 2765 m.getReturnType() == toRemove.getReturnType() &&
>> 2766 m.getName() == toRemove.getName() &&
>> 2767 arrayContentsEq(m.getParameterTypes(),
>> 2768 toRemove.getParameterTypes())) {
>> 2769 methods[i] = null;
>>
>>
>> Best regards,
>> Andrej Golovnin
>>
>>
>
