Class SumFunction

java.lang.Object
org.jaxen.function.SumFunction
All Implemented Interfaces:
Function

public class SumFunction extends Object implements Function

4.4 number sum(node-set)

The sum function returns the sum, for each node in the argument node-set, of the result of converting the string-values of the node to a number.
Author:
bob mcwhirter (bob @ werken.com)
See Also:
  • Constructor Details

    • SumFunction

      public SumFunction()
      Create a new SumFunction object.
  • Method Details

    • call

      public Object call(Context context, List args) throws FunctionCallException
      Returns the sum of its arguments.
      Specified by:
      call in interface Function
      Parameters:
      context - the context at the point in the expression when the function is called
      args - a list that contains exactly one item, also a List
      Returns:
      a Double containing the sum of the items in args.get(0)
      Throws:
      FunctionCallException - if args has more or less than one item; or if the first argument is not a List
    • evaluate

      public static Double evaluate(Object obj, Navigator nav) throws FunctionCallException
      Returns the sum of the items in a list. If necessary, each item in the list is first converted to a Double as if by the XPath number() function.
      Parameters:
      obj - a List of numbers to be summed
      nav - ignored
      Returns:
      the sum of the list
      Throws:
      FunctionCallException - if obj is not a List