I have a Java class that I'd like to use in Clojure. But, I want to use it as a Clojure map. What are the steps required to do so?
I've looked at the code for IPersistentMap -- should the Java class implement that? Or should there be some Clojure code which implements a protocol?
I know I could just write some mapping code, to explicitly convert the code from Java objects to maps, but that solution has a high effort/reward ratio. Also, I might encounter this same situation many more times.
Concrete example: I have a parser written in Java. I'd like to use that to parse some text, and then access the contents of the parsed data structure as though it were in Clojure maps:
(def parser (new MyParser))
(let [parse-tree (parser ... parse some text ...)]
((parse-tree :items) "itemid"))
The function bean came to mind:
Takes a Java object and returns a read-only implementation of the map abstraction based upon its JavaBean properties.
Example taken from the site:
user=> (import java.util.Date)
java.util.Date
user=> (def *now* (Date.))
#'user/*now*
user=> (bean *now*)
{:seconds 57, :date 13, :class java.util.Date,
:minutes 55, :hours 17, :year 110, :timezoneOffset -330,
:month 6, :day 2, :time 1279023957492}