com.myjavatools.lib.foundation
Class Iterators

java.lang.Object
  com.myjavatools.lib.foundation.Iterators

public class Iterators
extends java.lang.Object

Iterators is a utility class that contains static methods for iterators

Since:

5.0

Version:

5.0, 01/29/05

See Also:

Collection, Iterator, Filter

Nested Class Summary

static class

Iterators.EmptyIterator<T> EmptyIterator is a helper class that does not contain any elements and throws an exception when next() is called.

Constructor Summary

Iterators()

Method Summary

static <T> java.util.Collection<T>	cat(java.util.Collection<? extends T>... elements) Concatenates vararg Collections into one List
static <T> java.util.Iterator<T>	cat(java.lang.Iterable<? extends java.util.Iterator<T>> outerLoop) Creates an Iterator view of an Iterable consisting of Iterators
static <X> java.lang.Iterable<X>	cat(java.lang.Iterable<? extends X>... elements) Concatenates vararg Iterables into one List
static <T> java.util.Iterator<T>	cat(java.util.Iterator<T>... components) Creates an Iterator view of a sequence of Iterators
static java.lang.Iterable<java.lang.Character>	chars(java.lang.CharSequence sequence) returns an iterable good for using in a foreach loop

Methods inherited from class java.lang.Object

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

Constructor Detail

Iterators

public Iterators()

Method Detail

cat

public static <T> java.util.Iterator<T> cat(java.lang.Iterable<? extends java.util.Iterator<T>> outerLoop)

Creates an Iterator view of an Iterable consisting of Iterators

Parameters:

outerLoop - Iterable <? extends Iterator<T>> source iterators

Returns:

Iterator a compound iterator that scans the first iterator from the sequence, then the second, etc. Can be used with varargs: cat(iterator1, iterator2, iterator3) and with arrays: cat(iterators[]).

Example:

 List list1 = Arrays.asList(new String[] {"One", "Two", "Three"});
 List list2 = Arrays.asList(new String[] {"Four", "Five", "Six"});
 List list3 = Arrays.asList(new String[] {"One", "Two", "Three", "Four", "Five", "Six"}
 cat(Arrays.asList(new Iterator {list1.iterator(), list2.iterator()}))

returns the same as list3.iterator().

cat

public static <T> java.util.Iterator<T> cat(java.util.Iterator<T>... components)

Creates an Iterator view of a sequence of Iterators

Parameters:

components - Iterator[] source iterators

Returns:

Iterator a compound iterator that scans the first iterator from the sequence, then the second, etc. Can be used with varargs: cat(iterator1, iterator2, iterator3) and with arrays: cat(iterators[]).

Example:

 List list1 = Arrays.asList(new String[] {"One", "Two", "Three"});
 List list2 = Arrays.asList(new String[] {"Four", "Five", "Six"});
 List list3 = Arrays.asList(new String[] {"One", "Two", "Three", "Four", "Five", "Six"}
 cat(list1.iterator(), list2.iterator())

returns the same as list3.iterator().

cat

public static <X> java.lang.Iterable<X> cat(java.lang.Iterable<? extends X>... elements)

Concatenates vararg Iterables into one List

Parameters:

elements - Iterable<? extends X>...

Returns:

an Iterable view that has elements of the component Iterables.

Example:

cat(Arrays.asList(new String[] {"a", "b", "c"}), Arrays.asList(new String[] {"b", "a", "d"})) returns the same Iterable as Arrays.asList(new String[] {"a", "b", "c", "b", "a", "d"}).

cat

public static <T> java.util.Collection<T> cat(java.util.Collection<? extends T>... elements)

Concatenates vararg Collections into one List

Parameters:

elements - Collection<? extends T>...

Returns:

an Collection view that has elements of the component Collections.

Example:

cat(Arrays.asList(new String[] {"a", "b", "c"}), Arrays.asList(new String[] {"b", "a", "d"})) returns the same Collection as Arrays.asList(new String[] {"a", "b", "c", "b", "a", "d"}).

chars

public static java.lang.Iterable<java.lang.Character> chars(java.lang.CharSequence sequence)

returns an iterable good for using in a foreach loop

Parameters:

sequence - CharSequence to scan

Returns:

Iterable<Character>

Example:

for (char c : chars("this is an example"){ System.out.println("Character " + c); }