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From: BGB <cr88192@hotmail.com>
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Subject: Re: Define Type at runtime
Date: Thu, 08 Sep 2011 11:07:41 -0700
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On 9/8/2011 9:32 AM, Lew wrote:
> John wrote:
>> If I have a method:
>> public void someMethod(Object o){
>>       ...
>>       Entity<T>  entity;
>>       ....
>> }
>>
>> How could I define at runtime the type T if I have an Object?
>
> You can do an illegal cast with the help of '@SuppressWarnings("unchecked")' and a 'catch ( ClassCastException exc )'.
>
> You can under certain circumstances use a run-time type token of type 'Class<T>'.
>
> You can write your method to be type-safe in the first place and avoid the problem.
>
> Without some context we can't know what you really want.  Your question is far too non-specific.
>

and, probably, not to forget "instanceof".

eg, rather than, say:
Object obja;
try {
     SomeObject objb=(SomeObject)obja;
     ...
}catch(ClassCastException ex)
{
}

one could be like:
if(obja instanceof SomeObject)
{
     SomeObject objb=(SomeObject)obja;
     ...
}

which could be more useful if one wants to do the types N-way...

if(...)
{
     ...
}else if(...)
{
     ...
}else ...


or such...