Can we invoke a method using BCEL(byte code engineering library)

Hi i am new in Java bcel,So can anyone guide me in this problem.
I am searching for some techniques in BCEL to invoke a method of some class just like we use to invoke methods using Java Reflection.I have also tried a Java Assembler named "Jasmin" that used to interact with Operand Stack,Local variable array & Constant Pool etc so i guess this is the same containers with which our BCEL also interact with so then i am wondering why not then there exists a way through which we can invoke a method using BCEL IF this will happen in any case then kindly point it out some direction of help.
thanks in advance

856989 wrote:
I think i have clearly mentioned that "Tell me any way in doing this invocation in BCEL not in Reflection."
Why i not want to use reflection because it have "invocation overhead"Wrong.
If I dynamically load a class and reference it via a interface there is absolutely no difference in that and if I referenced the class statically and used it via an interface. The load and use process is exactly the same.
And the first uses "reflection".
If you use a proxy interface via something like java.lang.reflect.Method
then of course there is some overhead because there is in fact more classes involved. Just as if you had any other layer in any other code.
And even so unless you have actually profiled the application and found an actual bottleneck (and not just a measured impact) then even looking at it is a waste of time.
If it was me I would be far more concerned that inserting byte codes was correct for all cases.

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856989 wrote:
I think i have clearly mentioned that "Tell me any way in doing this invocation in BCEL not in Reflection."
Why i not want to use reflection because it have "invocation overhead"Wrong.
If I dynamically load a class and reference it via a interface there is absolutely no difference in that and if I referenced the class statically and used it via an interface. The load and use process is exactly the same.
And the first uses "reflection".
If you use a proxy interface via something like java.lang.reflect.Method
then of course there is some overhead because there is in fact more classes involved. Just as if you had any other layer in any other code.
And even so unless you have actually profiled the application and found an actual bottleneck (and not just a measured impact) then even looking at it is a waste of time.
If it was me I would be far more concerned that inserting byte codes was correct for all cases.

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Thanks for your reply, I am building a windows console application .And I want to convert the json data to object array to use in Method Base.Invoke method.
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Maybe you could select the correct language development forum here:
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Hi all,
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Thanks for your replies! I was editing my post last night to clarify it, but my connection went down and the edit was lost :(
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LRMK: Invoking a method such as in your example, where the method is inside the class itself, works fine. However for MVC's sake, I have a separate class called Invoicing with methods as below:
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I hope the problem is somewhat clearer now. I am a bit lost as to what might be causing this, or how to monitor what's going on inside the jvm. Any ideas? BTW, the OrderDetail class and its subclasses are JPA entities (though I don't think it should matter).
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864334 wrote:
I wanted to create a file(any kind of file .txt .csv .exe etc..) using pl/sql code in application server?And how is this "file" to be delivered?
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Techchies wrote:
Thanks for the response.
can you please eloberate "extra cpu time and obscurity". In case of refflection would it take more CPU time.Yes. Whether that matters or not is irrelevant. Actually, in practice, as alluded to above by EJP, it doesn't matter at all because you shouldn't be in a situation where you are choosing between the two. Either you actually need reflection, or you don't bother using it. Anything else is just "shiny thing" syndrome.
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</s:Application>
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Balakrishnan V

Can we invoke a method using BCEL(byte code engineering library)

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