gistfile1.pde

public class StringUtils { 
  public static boolean isBlank(String str) { 
    int strLen; 
    if (str == null || (strLen = str.length()) == 0) { 
      return true; 
    }  
    for (int i = 0; i < strLen; i++) { 
    if ((Character.isWhitespace(str.charAt(i)) == false)) { 
      return false; 
    } 
  }
}

(defmulti blank? class)
(defmethod blank? String [s](every? #{space} s))
(defmethod blank? nil [_] true)