Improvement in Ballerina FFI documentation

[lnash94]

Description

I was trying to write the ballerina external function that has Java implementation with my own class instead of the java pre build class. I was referring below documentation and it says that

The @java:Method annotation instructs the jBallerina compiler to link to the doSomethingInJava static method in the a.b.c.Foo Java class. 

https://ballerina.io/learn/ballerina-ffi/
But this doesn't mention where I need to put my own Java implementation (a.b.c.Foo java class) to have bindings. It would be helpful if it could be mentioned within the documentation.

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Describe the problem(s)

A detailed description of the purpose of this improvement.

[anupama-pathirage]

@HindujaB / @warunalakshitha Any update on this, Please check and fix it asap.