Returns the index within the specified Array of the first occurence of the
given object, starting at the specified index, and testing for equality using the
Java java.lang.Object.equals() method.
Returns -1 if the object is not found.
Parameters:
a
obj
If this parameter is null, the function
will seek the first occurence of null element.
fromIndex
lastIndexOf()
You may call this function in a method-like style:
a.indexOf(obj,fromIndex)