org.unbrokendome.gradle.plugins.gitversion.util.collections

Class CollectionUtils

java.lang.Object

org.unbrokendome.gradle.plugins.gitversion.util.collections.CollectionUtils

public final class CollectionUtils
extends java.lang.Object

Method Summary

Modifier and Type	Method and Description
static <T> T	findFirstCommonItem(java.lang.Iterable<T> ref, java.lang.Iterable<T> other) Finds the first item in a collection that also appears in another collection.
static <K,T> groovy.lang.Tuple2<K,T>	findFirstCommonItem(java.lang.Iterable<T> ref, java.util.Map<K,? extends java.lang.Iterable<T>> others) Finds the first item in a collection that also appears in any of a number of other collections.
static <T> T	findFirstCommonItem(java.util.Iterator<T> refIterator, java.util.Iterator<T> otherIterator) Finds the first item in an iterator that also appears in another iterator.
static <K,T> groovy.lang.Tuple2<K,T>	findFirstCommonItem(java.util.Iterator<T> refIterator, java.util.Map<K,? extends java.util.Iterator<T>> otherIterators) Finds the first item on an iterator that also appears on any of a number of other iterators.

Methods inherited from class java.lang.Object

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

Method Detail

findFirstCommonItem

public static <K,T> groovy.lang.Tuple2<K,T> findFirstCommonItem(java.util.Iterator<T> refIterator,
                                                                java.util.Map<K,? extends java.util.Iterator<T>> otherIterators)

Finds the first item on an iterator that also appears on any of a number of other iterators.

This could have easily been implemented by Set logic, but the iterators may represent possibly quite long sequences, so we don't want to consume more items than necessary.

The iterators that are passed in will be (partly) consumed by this method, so the caller should not make any assumptions about their state when the method returns.

Type Parameters:

K - the key type

T - the item type

Parameters:

refIterator - the iterator with the reference items to look for

otherIterators - a map containing a number of other iterators as values. The map keys may be used to identify from which iterator the matching item came.

Returns:

a Tuple2 that consists of:

1. the key of the iterator in otherIterators that contained the match;
2. the common item.

Returns null if refIterator is disjoint with all otherIterators.

findFirstCommonItem

public static <K,T> groovy.lang.Tuple2<K,T> findFirstCommonItem(java.lang.Iterable<T> ref,
                                                                java.util.Map<K,? extends java.lang.Iterable<T>> others)

Finds the first item in a collection that also appears in any of a number of other collections.

Type Parameters:

K - the key type

T - the item type

Parameters:

ref - the collection containing the reference items

others - a Map containing a number of other collections as values. The map keys may be used to identify from which collection the matching item came

Returns:

a Tuple2 that consists of:

1. the key of the iterator in otherIterators that contained the match;
2. the common item.

Returns null if ref is disjoint with all others.

findFirstCommonItem

public static <T> T findFirstCommonItem(java.util.Iterator<T> refIterator,
                                        java.util.Iterator<T> otherIterator)

Finds the first item in an iterator that also appears in another iterator.

Type Parameters:

T - the item type

Parameters:

refIterator - the iterator returning the reference items

otherIterator - the iterator to compare with

Returns:

the first common item, or null if the two iterators are disjoint

findFirstCommonItem

public static <T> T findFirstCommonItem(java.lang.Iterable<T> ref,
                                        java.lang.Iterable<T> other)

Finds the first item in a collection that also appears in another collection.

Type Parameters:

T - the item type

Parameters:

ref - the collection containing the reference items

other - the collection to compare with

Returns:

the first common item, or null if the two collections are disjoint