groovy.util

Class GroovyCollections

java.lang.Object

groovy.util.GroovyCollections

public class GroovyCollections
extends java.lang.Object

A Collections utility class

Author:

Paul King, Jim White

Constructor Summary

Constructors

Constructor and Description
GroovyCollections()

Method Summary

Modifier and Type	Method and Description
static java.util.List	combinations(java.util.Collection collections) Deprecated. use combinations(Iterable)
static java.util.List	combinations(java.lang.Iterable collections) Finds all combinations of items from the given Iterable aggregate of collections.
static java.util.List	combinations(java.lang.Object[] collections) Finds all combinations of items from the given collections.
static <T> T	max(java.util.Collection<T> items) Deprecated. use max(Iterable)
static <T> T	max(java.lang.Iterable<T> items) Selects the maximum value found in an Iterable.
static <T> T	max(T[] items) Selects the maximum value found in an array of items, so min([2, 4, 6] as Object[]) == 6.
static <T> T	min(java.util.Collection<T> items) Deprecated. use min(Iterable)
static <T> T	min(java.lang.Iterable<T> items) Selects the minimum value found in an Iterable of items.
static <T> T	min(T[] items) Selects the minimum value found in an array of items, so min([2, 4, 6] as Object[]) == 2.
static <T> java.util.Set<java.util.List<T>>	subsequences(java.util.List<T> items) Finds all non-null subsequences of a list.
static java.lang.Object	sum(java.util.Collection items) Deprecated. use sum(Iterable)
static java.lang.Object	sum(java.lang.Iterable items) Sums all the given items.
static java.lang.Object	sum(java.lang.Object[] items) Sums all the items from an array of items.
static java.util.List	transpose(java.util.List lists) Transposes the given lists.
static java.util.List	transpose(java.lang.Object[] lists) Transposes an array of lists.

Methods inherited from class java.lang.Object

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

Constructor Detail

GroovyCollections

public GroovyCollections()

Method Detail

combinations

public static java.util.List combinations(java.lang.Object[] collections)

Finds all combinations of items from the given collections.

Parameters:

collections - the given collections

Returns:

a List of the combinations found

See Also:

combinations(Collection)

subsequences

public static <T> java.util.Set<java.util.List<T>> subsequences(java.util.List<T> items)

Finds all non-null subsequences of a list. E.g. subsequences([1, 2, 3]) would be: [[1, 2, 3], [1, 3], [2, 3], [1, 2], [1], [2], [3]]

Parameters:

items - the List of items

Returns:

the subsequences from items

combinations

@Deprecated
public static java.util.List combinations(java.util.Collection collections)

Deprecated. use combinations(Iterable)

Parameters:

collections - the given collections

combinations

public static java.util.List combinations(java.lang.Iterable collections)

Finds all combinations of items from the given Iterable aggregate of collections. So, combinations([[true, false], [true, false]]) is [[true, true], [false, true], [true, false], [false, false]] and combinations([['a', 'b'],[1, 2, 3]]) is [['a', 1], ['b', 1], ['a', 2], ['b', 2], ['a', 3], ['b', 3]]. If a non-collection item is given, it is treated as a singleton collection, i.e. combinations([[1, 2], 'x']) is [[1, 'x'], [2, 'x']]. If an empty collection is found within the given collections, the result will be an empty list.

Parameters:

collections - the Iterable of given collections

Returns:

a List of the combinations found

Since:

2.2.0

transpose

public static java.util.List transpose(java.lang.Object[] lists)

Transposes an array of lists.

Parameters:

lists - the given lists

Returns:

a List of the transposed lists

See Also:

transpose(List)

transpose

public static java.util.List transpose(java.util.List lists)

Transposes the given lists. So, transpose([['a', 'b'], [1, 2]]) is [['a', 1], ['b', 2]] and transpose([['a', 'b', 'c']]) is [['a'], ['b'], ['c']].

Parameters:

lists - the given lists

Returns:

a List of the transposed lists

min

public static <T> T min(T[] items)

Selects the minimum value found in an array of items, so min([2, 4, 6] as Object[]) == 2.

Parameters:

items - an array of items

Returns:

the minimum value

min

@Deprecated
public static <T> T min(java.util.Collection<T> items)

Deprecated. use min(Iterable)

min

public static <T> T min(java.lang.Iterable<T> items)

Selects the minimum value found in an Iterable of items.

Parameters:

items - an Iterable

Returns:

the minimum value

Since:

2.2.0

max

public static <T> T max(T[] items)

Selects the maximum value found in an array of items, so min([2, 4, 6] as Object[]) == 6.

Parameters:

items - an array of items

Returns:

the maximum value

max

@Deprecated
public static <T> T max(java.util.Collection<T> items)

Deprecated. use max(Iterable)

max

public static <T> T max(java.lang.Iterable<T> items)

Selects the maximum value found in an Iterable.

Parameters:

items - a Collection

Returns:

the maximum value

Since:

2.2.0

sum

public static java.lang.Object sum(java.lang.Object[] items)

Sums all the items from an array of items.

Parameters:

items - an array of items

Returns:

the sum of the items

sum

@Deprecated
public static java.lang.Object sum(java.util.Collection items)

Deprecated. use sum(Iterable)

sum

public static java.lang.Object sum(java.lang.Iterable items)

Sums all the given items.

Parameters:

items - an Iterable of items

Returns:

the sum of the item

Since:

2.2.0