gistfile1.java

/* CREDIT: http://on-ruby.blogspot.com/2009/03/author-interview-venkat-subramaniam.html */

/* define method that takes an upperLimit Int and a function literal that accepts
*  a single Int parameter and returns a Boolean */
def totalSelectValuesInRange(upperLimit: Int, isOKToUse: Int => Boolean) = {
  /* Create a range by calling to on 1 (in RichInt wrapper for Int) */  
  val range = 1 to upperLimit 
  /* Fold left on range, starting with 0 - kind of like Ruby's 'inject' */ 
  (0 /: range) { (sum, number) =>    
    sum + (if (isOKToUse(number)) number else 0) } 
}

/* _ % 2 == 0 is a function literal - kind of like Ruby lambda, where _ is 
*  a placeholder for the Int that is passed in */
println "Total of even numbers from 1 to 10 is " + 
  totalSelectValuesInRange(10, _ % 2 == 0)

println "Total of odd numbers from 1 to 10 is " +
  totalSelectValuesInRange(10, _ % 2 == 1)