On Mon, Feb 28, 2011 at 11:13 AM, Jules <jules.gosn...@gmail.com> wrote: > I've had one last throw of the dice - a plan to intercept class > definition and remember associated bytecode so that my URLClassLoader > server could look it up when given the correspondong class name - with > no luck : > > ;; UNFINISHED > > ;; let's maintain a map of class-name : byte-code > (def class-name-to-byte-code (atom [])) > > ;; lets provide a class loader that wraps an existing one and > remembers the byte code that has been used > (defn make-class-loader-wrapper [class-loader] > (proxy > [java.lang.ClassLoader] > [] > (^Class defineClass [^String class-name ^"[B" byte-code ^Object > src-form] > (.defineClass class-loader class-name byte-code src-form) > (swap! class-name-to-byte-code conj [class-name byte-code]) > )))) > > ;; let's try to wrap-n-replace the existing class loader with our own > (alter-var-root clojure.lang.Compiler/LOADER make-class-loader- > wrapper) > (var-set clojure.lang.Compiler/LOADER (make-class-loader-wrapper > @clojure.lang.Compiler/LOADER)) > > It looks like clojure.lang.Compiler/LOADER has been doctored to stop > people like me playing with it :-) - I can't reset it to point to my > wrapper - or else I have made a mistake somewhere ? > > The whole thing is pretty horrible because ClassLoader is a class not > an interface and if I could install my wrapper i would actually have > to proxy every method - but you get the idea...
That's quite interesting -- it looks like you can dynamically replace the loader because it uses a Var. Maybe if you proxied DynamicClassLoader rather than just ClassLoader, and proxied all the methods to go through to DynamicClassLoader. DynamicClassLoader is not final so this should be possible. Something like: (let [old-loader (deref clojure.lang.Compiler/LOADER)] (proxy [clojure.lang.DynamicClassLoader] [] (^Class defineClass [^String class-name ^"[B" byte-code ^Object src-form] (.defineClass old-loader class-name byte-code src-form) (swap! class-name-to-byte-code conj [class-name byte-code]) )))) plus other methods that just punt to (.same-method old-loader args). -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en
