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From: Steven Simpson <ss@domain.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: methodhandle invoke with arguments cast error
Date: Sat, 07 Feb 2015 18:25:37 +0000
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On 06/02/15 05:41, Philipp Kraus wrote:
> On 2015-02-05 20:18:37 +0000, Arne Vajhøj said:
>
>> On 2/5/2015 2:57 PM, Philipp Kraus wrote:
>>> I use a method handle with this code:
>>>
>>> List<Object> args = new LinkedList();
>>> args.add( my object );
>>> args.add( new Double(5) );
>>>
>>> MethodHandle h = getMethodHandle_with_unreflect
>>> h.invokedWithArguments( args );
>>>
>>> The method, which is called shows
>>>
>>> public void doit( Integer x )
>>>
>>> so I get a cast error: Cannot cast java.lang.Double to 
>>> java.lang.Integer
>>> How can I do an explicit cast on the invokeMethodWithArguments?
>>
>> Stuff an Integer into the args List??
>
> Sorry, I forgot the information, that the list will be build 
> dynamically, so into the list can be pushed any numeric typ.

Is the method handle available when building the list?  You could get 
its MethodType, and scan over the parameter types for boxed primitives.  
If the corresponding argument is of type Number, call the appropriate 
XXXValue() method and push the result into the list.

-- 
ss at comp dot lancs dot ac dot uk