I need the ability to create one of a number of java classes which have
constructors taking a known list of parameters. There are a large enough
number of classes that having a set of conditions testing for each class
name would be unmanageable. The classes are from a third-party jar file so
I cannot modify them either.

The trouble is that new is special form and does not evaluate it's first
parameter so if I write an expression like
(new (Class/forName klassname)  param1 param2) it fails
because (Class/forName klassname)  is treated as the class name rather than
being evaluated first.

The closest I've got so far is to write the following macro

(defmacro make-proxy
  "Build proxy class from name and map"
  [klassname params] (list 'new (Class/forName klassname) '(:hostname
params) '(:port params)))

This gets me some of the way, I can now write
(make-proxy "com.example.foo" {:hostname "127.0.0.1 :port 9559})
but it only works for constant strings since the first parameter is
evaluated when the macro is expanded.

Can anyone suggest a solution?

thanks

Dave

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