jpaul.DataStructs
Class CompoundIterable<A,B>

java.lang.Object
  jpaul.DataStructs.CompoundIterable<A,B>

All Implemented Interfaces:

java.lang.Iterable<B>

public class CompoundIterable<A,B>
extends java.lang.Object
implements java.lang.Iterable<B>

CompoundIterable allows the construction of an Iterable by merging several smaller Iterables. Given an iterable with elements a0, a1, ..., ak, and a function f that transforms each ai into an iterable, the CompoundIterable will contain all elements from f(a0), followed by all the elements from f(a1) and so on.

The elements of a CompoundIterable are generated lazily, as we iterate over them. This tehcniqued is better than eager iteration in the case when (1) f is simple; (2) the original Iterable changes dynamically; (3) the number of traversals is small; or (3) the number of elements is very large.

Version:

$Id: CompoundIterable.java,v 1.3 2005/08/10 23:22:28 salcianu Exp $

Author:

Alexandru Salcianu - salcianu@alum.mit.edu

Constructor Summary

CompoundIterable(java.lang.Iterable<A> collA, Function<A,java.lang.Iterable<B>> a2iter)
Creates a CompoundIterable.

Method Summary

java.util.Iterator<B>	iterator()
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

CompoundIterable

public CompoundIterable(java.lang.Iterable<A> collA,
                        Function<A,java.lang.Iterable<B>> a2iter)

Creates a CompoundIterable.

Parameters:

collA - An iterable of elements of type A.

a2iter - A function that transforms each element from collA into an Iterable of Bs.

Method Detail

iterator

public java.util.Iterator<B> iterator()

Specified by:

iterator in interface java.lang.Iterable<B>

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object