I found an Issue called CLJ-944 on clojure.org. There you can find a fix for ClassCastException: clojure.lang.PersistentArrayMap cannot be cast to java.lang.Class issue The problem is: that the compiler injects an incorrect cast to clojure.lang.PersistentHashMap. In this case it should probably be cast to a clojure.lang.Associative, the highest common interface having the .containsKey method. Patch … Read more
What is Groovy on Grails? It doesn’t exist under this name anymore. It’s simply called Grails now. What is Groovy? Originally, a dynamic language for the JVM. However, since Groovy 2.0, both static and dynamic typing are supported. What is Grails? Grails (previously known as “Groovy on Grails”) is a programming framework based on Groovy … Read more
According to this SO thread, the solution is to use the non-primitive wrapper types; e.g., Integer instead of int.
There is indeed a Groovier Way. if (members) { //Some work } does everything if members is a collection. Null check as well as empty check (Empty collections are coerced to false). Hail Groovy Truth. 🙂