public class Object[]
extends Object
GDK enhancements for Object[].
| Type Params | Return Type | Name and description |
|---|---|---|
<T> |
public boolean |
any(Closure<?> predicate)Iterates over the contents of an Array, and checks whether a predicate is valid for at least one element. |
|
public boolean |
asBoolean()Coerces an object array to a boolean value. |
<T> |
public T |
asType(Class<T> type)Converts the given array to either a List, Set, or SortedSet. |
|
public Object |
average()Averages the items in an array. |
<T> |
public Object |
average(Closure<?> closure)Averages the result of applying a closure to each item of an array. |
<T> |
public List<List<T>> |
chop(int chopSizes)Chops the array into pieces, returning lists with sizes corresponding to the supplied chop sizes. |
<T> |
public List<List<T>> |
collate(int size)Collates an array. |
<T> |
public List<List<T>> |
collate(int size, int step)Collates an array into sub-lists. |
<T> |
public List<List<T>> |
collate(int size, boolean keepRemainder)Collates this array into sub-lists. |
<T> |
public List<List<T>> |
collate(int size, int step, boolean keepRemainder)Collates this array into sub-lists. |
<E, T> |
public List<T> |
collect(Closure<T> transform)Iterates through this Array transforming each item into a new value using the transform closure, returning a list of transformed values. |
<E, T, C> |
public C |
collect(C collector, Closure<? extends T> transform)Iterates through this Array transforming each item into a new value using the transform closure
and adding it to the supplied collector. |
<K, V, E> |
public Map<K, V> |
collectEntries()A variant of collectEntries using the identity closure as the transform. |
<K, V, E> |
public Map<K, V> |
collectEntries(Map<K, V> collector)A variant of collectEntries using the identity closure as the transform. |
<K, V, E> |
public Map<K, V> |
collectEntries(Closure<?> transform)Iterates through this array transforming each item using the transform closure
and returning a map of the resulting transformed entries. |
<K, V, E> |
public Map<K, V> |
collectEntries(Map<K, V> collector, Closure<?> transform)Iterates through this array transforming each item using the transform closure
and returning a map of the resulting transformed entries. |
<K, V, E> |
public Map<K, V> |
collectEntries(Function<? super E, K> keyTransform, Function<? super E, V> valueTransform)A variant of collectEntries for arrays with separate functions for transforming the keys and values. |
<K, V, E> |
public Map<K, V> |
collectEntries(Map<K, V> collector, Function<? super E, K> keyTransform, Function<? super E, V> valueTransform)A variant of collectEntries for arrays with separate functions for transforming the keys and values. |
<T, E> |
public List<T> |
collectMany(Closure<? extends Collection<? extends T>> projection)Projects each item from a source array to a collection and concatenates (flattens) the resulting collections into a single list. |
<T, E, C> |
public C |
collectMany(C collector, Closure<? extends Collection<? extends T>> projection)Projects each item from a source array to a collection and concatenates (flattens) the resulting collections into a single list. |
|
public boolean |
contains(Object value)Checks whether the array contains the given value. |
|
public Number |
count(Object value)Counts the number of occurrences of the given value inside this array. |
<T> |
public Number |
count(Closure<?> predicate)Counts the number of occurrences which satisfy the given closure from inside this array. |
<K, E> |
public Map<K, Integer> |
countBy(Closure<K> closure)Sorts all array members into groups determined by the supplied mapping closure and counts the group size. |
<E> |
public Map<E, Integer> |
countBy()Creates a multiset-like map of the array members. |
<T> |
public T[] |
drop(int num)Drops the given number of elements from the head of this array if they are available. |
<T> |
public T[] |
dropRight(int num)Drops the given number of elements from the tail of this array if they are available. |
<T> |
public T[] |
dropWhile(Closure<?> condition)Create a suffix of the given array by dropping as many elements as possible from the front of the original array such that calling the given closure condition evaluates to true when passed each of the dropped elements. |
<T> |
public T[] |
each(Closure<?> closure)Iterates through an array passing each array entry to the given closure. |
<T> |
public T[] |
eachWithIndex(Closure<?> closure)Iterates through an array, passing each array element and the element's index (a counter starting at zero) to the given closure. |
|
public boolean |
equals(List<?> right)Determines if the contents of this array are equal to the contents of the given list, in the same order. |
<T> |
public boolean |
every(Closure<?> predicate)Used to determine if the given predicate closure is valid (i.e. returns true for all items in this Array). |
<T> |
public T |
find(Closure<?> condition)Finds the first element in the array that matches the given closure condition. |
<T> |
public List<T> |
findAll()Finds the elements of the array matching the IDENTITY Closure (i.e. matching Groovy truth). |
<T> |
public List<T> |
findAll(Closure<?> condition)Finds all elements of the array matching the given Closure condition. |
<T> |
public int |
findIndexOf(Closure<?> condition)Iterates over the elements of an array and returns the index of the first item that satisfies the condition specified by the closure. |
<T> |
public int |
findIndexOf(int startIndex, Closure<?> condition)Iterates over the elements of an array, starting from a specified index, and returns the index of the first item that satisfies the condition specified by the closure. |
<T> |
public List<Number> |
findIndexValues(Closure<?> condition)Iterates over the elements of an array and returns the index values of the items that match the condition specified in the closure. |
<T> |
public List<Number> |
findIndexValues(Number startIndex, Closure<?> condition)Iterates over the elements of an array, starting from a specified index, and returns the index values of the items that match the condition specified in the closure. |
<T> |
public int |
findLastIndexOf(Closure<?> condition)Returns the index of the last item that matches the specified condition. |
<T> |
public int |
findLastIndexOf(int lowerBound, Closure<?> condition)Returns the index of the last item that matches the specified condition that is at or beyond the given index. |
<T> |
public T |
findResult()Iterates through the Array stopping once the first non-null result is found and returning that result. |
<T, U, V> |
public T |
findResult(V defaultResult)Iterates through the Array stopping once the first non-null result is found and returning that result. |
<S, T> |
public T |
findResult(Closure<T> condition)Iterates through the Array calling the given closure condition for each item but stopping once the first non-null result is found and returning that result. |
<S, T, U, V> |
public T |
findResult(U defaultResult, Closure<V> condition)Iterates through the Array calling the given closure condition for each item but stopping once the first non-null result is found and returning that result. |
<T> |
public Collection<T> |
findResults()Iterates through the Array collecting any non-null results. |
<T, U> |
public Collection<T> |
findResults(Closure<T> filteringTransform)Iterates through the Array transforming items using the supplied closure and collecting any non-null results. |
<T> |
public T |
first()Returns the first item from the array. |
|
public List<Object> |
flatten()Flattens an array. |
|
public Collection |
flattenMany(Closure<?> transform)Flatten an array. |
<T> |
public List<T> |
getAt(Range<?> range)Supports the subscript operator for an object array with a range giving the desired indices. |
<T> |
public List<T> |
getAt(IntRange range)Supports the subscript operator for an object array with an IntRange giving the desired indices. |
<T> |
public List<T> |
getAt(ObjectRange range)Supports the subscript operator for an object array with an ObjectRange giving the desired indices. |
<T> |
public List<T> |
getAt(EmptyRange<?> range)Supports the subscript operator for an object array with an EmptyRange. |
<T> |
public List<T> |
getAt(Collection<?> indices)Selects a List of items from an array using a Collection to identify the indices to be selected. |
<T> |
public IntRange |
getIndices()Returns indices of the array. |
<T> |
public List<T> |
grep()Iterates over the array returning each element that matches using the IDENTITY Closure as a filter - effectively returning all elements which satisfy Groovy truth. |
<T> |
public List<T> |
grep(Object filter)Iterates over the array of items and returns a collection of items that match the given filter - calling the DefaultGroovyMethods#isCase(Object,Object)#isCase(Object,Object) method used by switch statements. |
|
public String |
groovyToString()Returns Groovy's list-like string representation for an Object array. |
<K, T> |
public Map<K, List<T>> |
groupBy(Closure<K> closure)Sorts all array members into groups determined by the supplied mapping closure. |
|
public Map |
groupBy(Object closures)Sorts all array members into (sub)groups determined by the supplied mapping closures as per the Iterable variant of this method. |
|
public Map |
groupBy(List<Closure<?>> closures)Sorts all array members into (sub)groups determined by the supplied mapping closures as per the list variant of this method. |
<T, K> |
public Map<K, List<T>> |
groupByMany(Closure<? extends Iterable<? extends K>> keyFn)Groups all array members into (sub)groups determined by the supplied key mapping closure. |
<T, U, K> |
public Map<K, List<U>> |
groupByMany(Closure<? extends U> valueFn, Closure<? extends Iterable<? extends K>> keyFn)Groups all members from the array into (sub)groups determined by the supplied key mapping closure. |
<T> |
public T |
head()Returns the first item from the Object array. |
|
public int |
indexOf(Object object)Returns the index of the first occurrence of the specified element in the array. |
<T> |
public Map<Integer, T> |
indexed()Zips an object array with indices in (index, value) order starting from index 0. |
<T> |
public Map<Integer, T> |
indexed(int offset)Zips an object array with indices in (index, value) order starting from a given index. |
<T> |
public T[] |
init()Returns the items from the Object array excluding the last item. |
<E, T, V> |
public T |
inject(Closure<V> closure)Iterates through the given array, passing the first two elements to the closure. |
<E, T, U, V> |
public T |
inject(U initialValue, Closure<V> closure)Iterates through the given array, passing in the initial value and the first element to the closure. |
<E, T, V> |
public List<T> |
injectAll(Closure<V> closure)Iterates through the given array, injecting values as per inject but returns the list of all calculated values instead of just the final result. |
<E, T, U, V> |
public List<T> |
injectAll(U initialValue, Closure<V> closure)Iterates through the given array, injecting values as per inject but returns the list of all calculated values instead of just the final result. |
<T> |
public boolean |
isSorted()Determines if the array is sorted in natural order using a NumberAwareComparator. |
<T> |
public boolean |
isSorted(Comparator<? super T> comparator)Determines if the array is sorted according to the given Comparator. |
<T> |
public boolean |
isSorted(Closure<?> closure)Determines if the array is sorted using the given Closure to determine order. |
<T> |
public Iterator<T> |
iterator()Returns an Iterator which traverses the given array in index order. |
|
public String |
join()Concatenates the string representation of each item in this array. |
|
public String |
join(String separator)Concatenates the string representation of each item in this array, with the given String as a separator between each item. |
<T> |
public T |
last()Returns the last item from the array. |
|
public int |
lastIndexOf(Object object)Returns the index of the last occurrence of the specified element in the array. |
<T> |
public T |
max()Adds max() method to Object arrays. |
<T> |
public T |
max(Comparator<? super T> comparator)Selects the maximum value found from the Object array using the given comparator. |
<T> |
public T |
max(Closure<?> closure)Selects the maximum value found from the Object array using the closure to determine the correct ordering. |
<T> |
public T |
min()Adds min() method to Object arrays. |
<T> |
public T |
min(Comparator<? super T> comparator)Selects the minimum value found from the Object array using the given comparator. |
<T> |
public T |
min(Closure<?> closure)Selects the minimum value found from the Object array using the closure to determine the correct ordering. |
<T> |
public T[] |
minus(Iterable<?> removeMe)Creates a new array composed of the elements of the first array minus the elements of the given Iterable. |
<T> |
public T[] |
minus(Object[] removeMe)Creates a new array composed of the elements of the first array minus the elements of the given array. |
<T> |
public T[] |
minus(Object removeMe)Creates a new array composed of the elements of the given array minus every occurrence the given object. |
<T> |
public int |
partitionPoint(IntRange range, Predicate<T> condition)Returns the index of the partition point according to the given predicate (the index of the first element of the second partition). |
<T> |
public int |
partitionPoint(Predicate<T> condition)Returns the index of the partition point according to the given predicate (the index of the first element of the second partition). |
<T> |
public T[] |
plus(Collection<?> right)Creates an array containing elements from an original array plus those from a Collection. |
<T> |
public T[] |
plus(Iterable<?> right)Creates an array containing elements from an original array plus those from an Iterable. |
<T> |
public T[] |
plus(Object[] right)Creates an array as a union of two arrays. |
<T> |
public T[] |
plus(Object right)Creates an array containing elements from an original array plus an additional appended element. |
<T> |
public void |
putAt(IntRange range, T[] source)A helper method to allow arrays to be set with subscript operators. |
<T> |
public void |
putAt(IntRange range, Iterable<T> source)A helper method to allow arrays to be set with subscript operators. |
<T> |
public T[] |
reverse()Creates a new array containing items which are the same as this array but in reverse order. |
<T> |
public T[] |
reverse(boolean mutate)Reverses the items in an array. |
<T> |
public T[] |
reverseEach(Closure<?> closure)Iterates over each element of the array in the reverse order. |
<T> |
public void |
shuffle()Randomly reorders the elements of the specified array. |
<T> |
public void |
shuffle(Random rnd)Randomly reorders the elements of the specified array using the specified random instance as the source of randomness. |
<T> |
public T[] |
shuffled()Creates a new array containing the elements of the specified array but in a random order. |
<T> |
public T[] |
shuffled(Random rnd)Creates a new array containing the elements of the specified array but in a random order using the specified random instance as the source of randomness. |
|
public int |
size()Provides the standard Groovy size() method for an array. |
<T> |
public T[] |
sort()Modifies this array so that its elements are in sorted order. |
<T> |
public T[] |
sort(boolean mutate)Sorts the given array into sorted order. |
<T> |
public T[] |
sort(Comparator<? super T> comparator)Sorts the given array into sorted order using the given comparator. |
<T> |
public T[] |
sort(boolean mutate, Comparator<? super T> comparator)Sorts the elements from this array into sorted order as determined by the given comparator. |
<T> |
public T[] |
sort(Closure<?> closure)Sorts the elements from this array into a newly created array using the Closure to determine the correct ordering. |
<T> |
public T[] |
sort(IntRange range, Closure<?> closure)Sorts the elements from this array with index values in the given index range into a newly created array using the Closure to determine the correct ordering. |
<T> |
public T[] |
sort(boolean mutate, Closure<?> closure)Sorts the elements from this array into sorted order using the Closure to determine the correct ordering. |
<T> |
public T[] |
sort(IntRange range, boolean mutate, Closure<?> closure)Sorts the elements with index values in the given index range into sorted order using the Closure to determine the correct ordering. |
<T> |
public Collection<Collection<T>> |
split(Closure<?> closure)Splits all items into two collections based on the closure condition. |
<T> |
public Stream<T> |
stream()Returns a sequential Stream with the specified array as its source. |
|
public Object |
sum()Sums the items in an array. |
|
public Object |
sum(Object initialValue)Sums the items in an array, adding the result to some initial value. |
<T> |
public Object |
sum(Closure<?> closure)Sums the result of applying a closure to each item of an array. |
<T> |
public Object |
sum(Object initialValue, Closure<?> closure)Sums the result of applying a closure to each item of an array to some initial value. |
<T> |
public T[] |
swap(int i, int j)Swaps two elements at the specified positions. |
<T> |
public T[] |
tail()Returns the items from the array excluding the first item. |
<T> |
public T[] |
take(int num)Returns the first num elements from the head of this array.
|
<T> |
public T[] |
takeRight(int num)Returns the last num elements from the tail of this array.
|
<T> |
public T[] |
takeWhile(Closure<?> condition)Returns the longest prefix of this array where each element passed to the given closure evaluates to true. |
<T> |
public List<T> |
toList()Converts this array to a List of the same size, with each element added to the list. |
<T> |
public Set<T> |
toSet()Converts this array to a Set, with each unique element added to the set. |
<T> |
public T[] |
toSorted()Returns a sorted version of the given array using the supplied comparator. |
<T> |
public T[] |
toSorted(Comparator<? super T> comparator)Returns a sorted version of the given array using the supplied comparator to determine the resulting order. |
<T> |
public T[] |
toSorted(Closure<?> closure)Sorts the elements from this array into a newly created array using the Closure to determine the correct ordering. |
|
public SpreadMap |
toSpreadMap()Creates a spreadable map from this array. |
|
public String |
toString()Returns the string representation of the given array. |
<T> |
public T[] |
toUnique()Returns a new Array containing the items from the original Array but with duplicates removed using the natural ordering of the items in the array. |
<T> |
public T[] |
toUnique(Comparator<? super T> comparator)Returns a new Array containing the items from the original Array but with duplicates removed with the supplied comparator determining which items are unique. |
<T> |
public T[] |
toUnique(Closure<?> closure)Returns a new Array containing the items from the original Array but with duplicates removed with the supplied closure determining which items are unique. |
|
public Object[] |
union(Collection<?> right)Creates an object array containing elements from an original array plus those from a Collection. |
|
public Object[] |
union(Iterable<?> right)Creates an Object array containing elements from an original array plus those from an Iterable. |
|
public Object[] |
union(Object[] right)Creates an Object array as a union of two arrays. |
|
public Object[] |
union(Object right)Creates an Object array containing elements from an original array plus an additional appended element. |
<K, V> |
public Map<K, V> |
withCollectedKeys(Function<? super V, K> keyTransform)A variant of withCollectedKeys for arrays. |
<K, V> |
public Map<K, V> |
withCollectedKeys(Map<K, V> collector, Function<? super V, K> keyTransform)A variant of withCollectedKeys for arrays. |
<K, V> |
public Map<K, V> |
withCollectedValues(Function<? super K, V> valueTransform)A variant of withCollectedValues for arrays. |
<K, V> |
public Map<K, V> |
withCollectedValues(Map<K, V> collector, Function<? super K, V> valueTransform)A variant of withCollectedValues for arrays. |
<T> |
public List<Tuple2<T, Integer>> |
withIndex()Zips an object array with indices in (value, index) order. |
<T> |
public List<Tuple2<T, Integer>> |
withIndex(int offset)Zips an object array with indices in (value, index) order starting from a given index. |
| Methods inherited from class | Name |
|---|---|
class Object |
addShutdownHook, any, any, asBoolean, asType, collect, collect, collect, dump, each, eachMatch, eachMatch, eachWithIndex, every, every, find, find, findAll, findAll, findIndexOf, findIndexOf, findIndexValues, findIndexValues, findLastIndexOf, findLastIndexOf, findResult, findResult, findResult, findResult, getAt, getMetaClass, getMetaPropertyValues, getProperties, grep, grep, hasProperty, identity, inject, inject, inspect, invokeMethod, is, isCase, isNotCase, iterator, metaClass, print, print, printf, printf, println, println, println, putAt, respondsTo, respondsTo, setMetaClass, sleep, sleep, split, sprintf, sprintf, stream, tap, toString, use, use, use, with, with, withCloseable, withCloseable, withMethodClosure, withStream, withStream, withTraits |
Iterates over the contents of an Array, and checks whether a predicate is valid for at least one element.
predicate - the closure predicate used for matchingCoerces an object array to a boolean value. An Object array is false if the array is of length 0. and to true otherwise
Converts the given array to either a List, Set, or SortedSet. If the given class is something else, the call is deferred to DefaultGroovyMethods#asType(Object,Class)#asType(Object,Class).
type - the desired classAverages the items in an array. This is equivalent to invoking the "plus" method on all items in the array and then dividing by the total count using the "div" method for the resulting sum.
assert 3 == ([1, 2, 6] as Integer[]).average()
Averages the result of applying a closure to each item of an array.
array.average(closure) is equivalent to:
array.collect(closure).average().
def (nums, strings) = [[1, 3] as Integer[], ['to', 'from'] as String[]]
assert 20 == nums.average { it * 10 }
assert 3 == strings.average { it.size() }
assert 3 == strings.average (String::size)
closure - a single parameter closure that returns a (typically) numeric value.Chops the array into pieces, returning lists with sizes corresponding to the supplied chop sizes. If the array isn't large enough, truncated (possibly empty) pieces are returned. Using a chop size of -1 will cause that piece to contain all remaining items from the array.
chopSizes - the sizes for the returned piecesCollates an array.
size - the length of each sub-list in the returned listCollates an array into sub-lists.
size - the length of each sub-list in the returned liststep - the number of elements to step through for each sub-listCollates this array into sub-lists.
size - the length of each sub-list in the returned listkeepRemainder - if true, any remaining elements are returned as sub-lists; otherwise, they are discardedCollates this array into sub-lists.
size - the length of each sub-list in the returned liststep - the number of elements to step through for each sub-listkeepRemainder - if true, any remaining elements are returned as sub-lists; otherwise, they are discarded Iterates through this Array transforming each item into a new value using the
transform closure, returning a list of transformed values.
transform - the closure used to transform each item of the Array Iterates through this Array transforming each item into a new value using the transform closure
and adding it to the supplied collector.
Integer[] nums = [1,2,3]
List answer = []
nums.collect(answer) { it * 2 }
assert answer == [2,4,6]
collector - the Collection to which the transformed values are addedtransform - the closure used to transform each itemA variant of collectEntries using the identity closure as the transform.
A variant of collectEntries using the identity closure as the transform.
collector - the Map into which the transformed entries are put Iterates through this array transforming each item using the transform closure
and returning a map of the resulting transformed entries.
def letters = "abc"
def nums = [0, 1, 2] as Integer[]
// collect letters with index using list style
assert nums.collectEntries { index -> [index, letters[index]] } == [0:'a', 1:'b', 2:'c']
// collect letters with index using map style
assert nums.collectEntries { index -> [(index): letters[index]] } == [0:'a', 1:'b', 2:'c']
Note: When using the list-style of result, the behavior is 'def (key, value) = listResultFromClosure'.
While we strongly discourage using a list of size other than 2, Groovy's normal semantics apply in this case;
throwing away elements after the second one and using null for the key or value for the case of a shortened list.
transform - the closure used for transforming, which has an item from self as the parameter and
should return a Map.Entry, a Map or a two-element list containing the resulting key and value Iterates through this array transforming each item using the transform closure
and returning a map of the resulting transformed entries.
def letters = "abc"
def nums = [0, 1, 2] as Integer[]
// collect letters with index
assert nums.collectEntries( [:] ) { index -> [index, letters[index]] } == [0:'a', 1:'b', 2:'c']
assert nums.collectEntries( [4:'d'] ) { index -> [(index+1): letters[index]] } == [1:'a', 2:'b', 3:'c', 4:'d']
Note: When using the list-style of result, the behavior is 'def (key, value) = listResultFromClosure'.
While we strongly discourage using a list of size other than 2, Groovy's normal semantics apply in this case;
throwing away elements after the second one and using null for the key or value for the case of a shortened list.
If your collector Map doesn't support null keys or values, you might get a runtime error, e.g. NullPointerException or IllegalArgumentException.
collector - the Map into which the transformed entries are puttransform - the closure used for transforming, which has an item from self as the parameter and
should return a Map.Entry, a Map or a two-element list containing the resulting key and valueA variant of collectEntries for arrays with separate functions for transforming the keys and values.
String[] languages = ['Groovy', 'Java', 'Kotlin', 'Scala']
def firstLetter = (s) -> s[0]
assert languages.collectEntries(firstLetter, String::size) == [G:6, J:4, K:6, S:5]
keyTransform - a function for transforming array elements into keysvalueTransform - a function for transforming array elements into valuesA variant of collectEntries for arrays with separate functions for transforming the keys and values. The supplied collector map is used as the destination for transformed entries.
collector - the Map into which the transformed entries are putkeyTransform - a function for transforming array elements into keysvalueTransform - a function for transforming array elements into valuesProjects each item from a source array to a collection and concatenates (flattens) the resulting collections into a single list.
def nums = [1, 2, 3, 4, 5, 6] as Object[]
def squaresAndCubesOfEvens = nums.collectMany{ it % 2 ? [] : [it**2, it**3] }
assert squaresAndCubesOfEvens == [4, 8, 16, 64, 36, 216]
projection - a projecting Closure returning a collection of itemsProjects each item from a source array to a collection and concatenates (flattens) the resulting collections into a single list.
def nums = [1, 2, 3, 4, 5, 6] as Object[]
def squaresAndCubesOfEvens = nums.collectMany{ it % 2 ? [] : [it**2, it**3] }
assert squaresAndCubesOfEvens == [4, 8, 16, 64, 36, 216]
collector - an initial collection to add the projected items toprojection - a projecting Closure returning a collection of itemsChecks whether the array contains the given value.
value - the value being searched for Counts the number of occurrences of the given value inside this array.
Comparison is done using Groovy's == operator (using
compareTo(value) == 0 or equals(value) ).
value - the value being searched forCounts the number of occurrences which satisfy the given closure from inside this array.
predicate - a closure conditionSorts all array members into groups determined by the supplied mapping closure and counts the group size. The closure should return the key that each item should be grouped by. The returned Map will have an entry for each distinct key returned from the closure, with each value being the frequency of items occurring for that group.
Example usage:
assert ([1,2,2,2,3] as Object[]).countBy{ it % 2 } == [1:2, 0:3]
closure - a closure mapping items to the frequency keysCreates a multiset-like map of the array members.
Example usage:
assert [1:2, 2:2, 3:1] == ([1,2,1,2,3] as Object[]).countBy()
Drops the given number of elements from the head of this array if they are available.
String[] strings = [ 'a', 'b', 'c' ]
assert strings.drop( 0 ) == [ 'a', 'b', 'c' ] as String[]
assert strings.drop( 2 ) == [ 'c' ] as String[]
assert strings.drop( 5 ) == [] as String[]
num - the number of elements to drop from this arraynum ones, or else the empty array, if this
array has less than num elements.Drops the given number of elements from the tail of this array if they are available.
String[] strings = [ 'a', 'b', 'c' ]
assert strings.dropRight( 0 ) == [ 'a', 'b', 'c' ] as String[]
assert strings.dropRight( 2 ) == [ 'a' ] as String[]
assert strings.dropRight( 5 ) == [] as String[]
num - the number of elements to drop from this arraynum ones, or else the empty array, if this
array has less than num elements.Create a suffix of the given array by dropping as many elements as possible from the front of the original array such that calling the given closure condition evaluates to true when passed each of the dropped elements.
def nums = [ 1, 3, 2 ] as Integer[]
assert nums.dropWhile{ it <= 3 } == [ ] as Integer[]
assert nums.dropWhile{ it < 3 } == [ 3, 2 ] as Integer[]
assert nums.dropWhile{ it != 2 } == [ 2 ] as Integer[]
assert nums.dropWhile{ it == 0 } == [ 1, 3, 2 ] as Integer[]
condition - the closure that must evaluate to true to
continue dropping elementsIterates through an array passing each array entry to the given closure.
String[] letters = ['a', 'b', 'c']
String result = ''
letters.each{ result += it }
assert result == 'abc'
closure - the closure applied on each array entryIterates through an array, passing each array element and the element's index (a counter starting at zero) to the given closure.
String[] letters = ['a', 'b', 'c']
String result = ''
letters.eachWithIndex{ letter, index -> result += "$index:$letter" }
assert result == '0:a1:b2:c'
closure - a Closure to operate on each array entry Determines if the contents of this array are equal to the
contents of the given list, in the same order. This returns
false if either collection is null.
right - the List being comparedtrue if the contents of both collections are equal. Used to determine if the given predicate closure is valid (i.e. returns
true for all items in this Array).
predicate - the closure predicate used for matchingFinds the first element in the array that matches the given closure condition. Example:
def list = [1,2,3] as Integer[]
assert 2 == list.find { it > 1 }
assert null == list.find { it > 5 }
condition - a closure conditionFinds the elements of the array matching the IDENTITY Closure (i.e. matching Groovy truth).
def items = [1, 2, 0, false, true, '', 'foo', [], [4, 5], null] as Object[]
assert items.findAll() == [1, 2, true, 'foo', [4, 5]]
Finds all elements of the array matching the given Closure condition.
def items = [1,2,3,4] as Integer[]
assert [2,4] == items.findAll { it % 2 == 0 }
condition - a closure conditionIterates over the elements of an array and returns the index of the first item that satisfies the condition specified by the closure.
condition - the matching conditionIterates over the elements of an array, starting from a specified index, and returns the index of the first item that satisfies the condition specified by the closure.
startIndex - start matching from this indexcondition - the matching conditionIterates over the elements of an array and returns the index values of the items that match the condition specified in the closure.
condition - the matching conditionIterates over the elements of an array, starting from a specified index, and returns the index values of the items that match the condition specified in the closure.
startIndex - start matching from this indexcondition - the matching conditionReturns the index of the last item that matches the specified condition.
def array = new Number[]{1, 2, 1, 2, 1}
assert array.findLastIndexOf{it==1} == 4
assert array.findLastIndexOf{it==2} == 3
assert array.findLastIndexOf{it==3} == -1
assert array.findLastIndexOf{it>=0} == 4
assert array.findLastIndexOf{it<=0} == -1
def empty = new Object[0]
assert empty.findLastIndexOf {true} == -1
condition - the matching conditionReturns the index of the last item that matches the specified condition that is at or beyond the given index.
def array = new Number[]{3, 1, 2, 1, 2, 1}
assert array.findLastIndexOf(1,{it==0}) == -1
assert array.findLastIndexOf(1,{it==1}) == 5
assert array.findLastIndexOf(1,{it==2}) == 4
assert array.findLastIndexOf(1,{it==3}) == -1
assert array.findLastIndexOf(0,{it==3}) == 0
def empty = new Object[0]
assert empty.findLastIndexOf( 2,{true}) == -1
assert empty.findLastIndexOf(-2,{true}) == -1
lowerBound - the minimum indexcondition - the matching conditionIterates through the Array stopping once the first non-null result is found and returning that result. If all results are null, null is returned.
Iterates through the Array stopping once the first non-null result is found and returning that result. If all are null, the defaultResult is returned.
defaultResult - an Object that should be returned if all elements are nullIterates through the Array calling the given closure condition for each item but stopping once the first non-null result is found and returning that result. If all results are null, null is returned.
condition - a closure that returns a non-null value to indicate that processing should stop and the value should be returnedIterates through the Array calling the given closure condition for each item but stopping once the first non-null result is found and returning that result. If all are null, the defaultResult is returned.
defaultResult - a value that should be returned if all closure results are nullcondition - a closure that returns a non-null value to indicate that processing should stop and the value should be returnedIterates through the Array collecting any non-null results.
Iterates through the Array transforming items using the supplied closure and collecting any non-null results.
filteringTransform - a closure that should return either a non-null transformed value or null for items which should be discardedReturns the first item from the array.
def array = [3, 4, 2].toArray()
assert array.first() == 3
Flattens an array. This array and any nested arrays or collections have their contents (recursively) added to the new collection.
Flatten an array. This array and any nested arrays, collections or optionals have their contents (recursively) added to a new collection. A transform is applied to any leaf nodes before further flattening.
transform - a transform applied to any leaf elementsSupports the subscript operator for an object array with a range giving the desired indices.
range - a RangeSupports the subscript operator for an object array with an IntRange giving the desired indices.
range - an IntRangeSupports the subscript operator for an object array with an ObjectRange giving the desired indices.
range - an ObjectRangeSupports the subscript operator for an object array with an EmptyRange.
range - an EmptyRangeSelects a List of items from an array using a Collection to identify the indices to be selected.
indices - a collection of indicesReturns indices of the array.
Example:
String[] letters = ['a', 'b', 'c', 'd']
assert 0..<4 == letters.indices
Iterates over the array returning each element that matches using the IDENTITY Closure as a filter - effectively returning all elements which satisfy Groovy truth.
Example:
def items = [1, 2, 0, false, true, '', 'foo', [], [4, 5], null] as Object[]
assert items.grep() == [1, 2, true, 'foo', [4, 5]]
Iterates over the array of items and returns a collection of items that match the given filter - calling the DefaultGroovyMethods#isCase(Object,Object)#isCase(Object,Object) method used by switch statements. This method can be used with different kinds of filters like regular expressions, classes, ranges etc. Example:
def items = ['a', 'b', 'aa', 'bc', 3, 4.5] as Object[]
assert items.grep( ~/a+/ ) == ['a', 'aa']
assert items.grep( ~/../ ) == ['aa', 'bc']
assert items.grep( Number ) == [ 3, 4.5 ]
assert items.grep{ it.toString().size() == 1 } == [ 'a', 'b', 3 ]
filter - the filter to perform on each element of the array (using the DefaultGroovyMethods#isCase(java.lang.Object, java.lang.Object) method) Returns Groovy's list-like string representation for an Object array.
This is used by Groovy's formatting infrastructure (e.g., GString interpolation,
println, assert messages). By default, it delegates to
FormatHelper#toArrayString(Object[])#toArrayString(Object[]).
If disabled, e.g. via -Dgroovy.extension.disable=groovyToString(Object[]),
the JDK's default array toString() is used instead.
Alternatively, you have the option to provide a replacement extension method in an extension module
to customize how arrays are displayed throughout Groovy.
Sorts all array members into groups determined by the supplied mapping closure. The closure should return the key that this item should be grouped by. The returned LinkedHashMap will have an entry for each distinct key returned from the closure, with each value being a list of items for that group.
Example usage:
Integer[] items = [1,2,3,4,5,6]
assert [0:[2,4,6], 1:[1,3,5]] == items.groupBy { it % 2 }
closure - a closure mapping entries on keysSorts all array members into (sub)groups determined by the supplied mapping closures as per the Iterable variant of this method.
closures - an array of closures, each mapping entries on keysSorts all array members into (sub)groups determined by the supplied mapping closures as per the list variant of this method.
closures - a list of closures, each mapping entries on keysGroups all array members into (sub)groups determined by the supplied key mapping closure. The closure should return a list of keys applicable to a member. The member will be grouped under each key from the list. Example usage finding the words with capital letters:
String[] words = ['TO', 'be', 'Or', 'nOT', 'To', 'be']
assert words.groupByMany(w -> w.toSet().grep(~'[A-Z]')) == [T:['TO', 'nOT', 'To'], O:['TO', 'Or', 'nOT']]
If the lists of generated keys are all of size 1, the result will be the same as
groupBy with a closure returning the value in the key list:
String[] animals = ['cat', 'dog', 'bird', 'pony']
assert animals.groupByMany(a -> [a.size()]) == animals.groupBy(String::size)
keyFn - a closure returning an Iterable of keys for each elementGroups all members from the array into (sub)groups determined by the supplied key mapping closure. The key mapping closure should return a list of keys applicable to a member. The value returned by mapping the member with the value mapping closure will be grouped under each key from the list.
valueFn - a closure which can transform each member before collectingkeyFn - a closure returning an Iterable of keys for each memberReturns the first item from the Object array.
def array = [3, 4, 2].toArray()
assert array.head() == 3 Returns the index of the first occurrence of the specified element in the
array. That is, the lowest index i such that
Objects.equals(array[i], object) or -1 if there is no such index.
String[] array = ['foo','bar','foo']
assert array.indexOf('foo') == 0
assert array.indexOf('bar') == 1
assert array.indexOf('baz') == -1
assert array.indexOf(12345) == -1
Zips an object array with indices in (index, value) order starting from index 0.
Example usage:
String[] letters = 'A'..'C'
assert [0: 'A', 1: 'B', 2: 'C'] == letters.indexed()
Zips an object array with indices in (index, value) order starting from a given index.
Example usage:
String[] letters = 'A'..'C'
assert [5: 'A', 6: 'B', 7: 'C'] == letters.indexed(5)
assert ["1: A", "2: B", "3: C"] == letters.indexed(1).collect { idx, str -> "$idx: $str" }
offset - an index to start fromReturns the items from the Object array excluding the last item.
String[] strings = ["a", "b", "c"]
def result = strings.init()
assert result.length == 2
assert strings.class.componentType == String
Iterates through the given array, passing the first two elements to the closure. The result is passed back (injected) to the closure along with the third element and so on until all array elements have been consumed.
def array = new Number[] {1, 2, 3, 4}
def value = array.inject { acc, val -> acc * val }
assert value == 24
array = new Object[] {['a','b'], ['b','c'], ['d','b']}
value = array.inject { acc, val -> acc.intersect(val) }
assert value == ['b']
array = new String[] {'t', 'i', 'm'}
value = array.inject { acc, val -> acc + val }
assert value == 'tim'
closure - a closureIterates through the given array, passing in the initial value and the first element to the closure. The result is sent back (injected) with the second element. The new result is injected back into the closure with the third element and so on until all elements have been consumed.
def array = new Number[] {2, 3, 4}
def value = array.inject(1) { acc, val -> acc * val }
assert value == 24
array = new Object[] {['a','b'], ['b','c'], ['d','b']}
value = array.inject(['a','b','c']) { acc, val -> acc.intersect(val) }
assert value == ['b']
array = new String[] {'t', 'i', 'm'}
value = array.inject("") { acc, val -> acc + val }
assert value == 'tim'
initialValue - base valueclosure - a closureIterates through the given array, injecting values as per inject but returns the list of all calculated values instead of just the final result.
Iterates through the given array, injecting values as per inject but returns the list of all calculated values instead of just the final result.
Integer[] nums = 1..5
var prefixSum = nums.injectAll(0, Integer::sum)
Arrays.parallelPrefix(nums, Integer::sum) // built-in JDK mutating method
assert nums == prefixSum
Determines if the array is sorted in natural order using a NumberAwareComparator.
Integer[] nums = [1, 2, 3]
assert nums.isSorted()
Integer[] unsorted = [3, 1, 2]
assert !unsorted.isSorted()
Determines if the array is sorted according to the given Comparator. This is efficient — it checks adjacent pairs in a single pass and short-circuits on the first out-of-order pair.
String[] words = ["hello","Hey","hi"]
assert words.isSorted(String.CASE_INSENSITIVE_ORDER)
comparator - a Comparator used for the comparisonDetermines if the array is sorted using the given Closure to determine order.
If the Closure has two parameters it is used like a traditional Comparator. Otherwise, the Closure is assumed to take a single parameter and return a Comparable (typically an Integer) which is then used for further comparison.
closure - a 1 or 2 arg Closure used to determine the orderingReturns an Iterator which traverses the given array in index order.
Concatenates the string representation of each item in this array.
def array = new Number[]{1,2L,3G}
assert array.join() == "123"
Concatenates the string representation of each item in this array, with the given String as a separator between each item.
Serializable[] array = [1,2L,-3G]
assert array.join("+") == "1+2+-3"
separator - a String separatorReturns the last item from the array.
def array = [3, 4, 2].toArray()
assert array.last() == 2
Returns the index of the last occurrence of the specified element in the
array. That is, the highest index i such that
Objects.equals(array[i], object) or -1 if there is no such index.
String[] array = ['foo','bar','foo']
assert array.lastIndexOf('foo') == 2
assert array.lastIndexOf('bar') == 1
assert array.lastIndexOf('baz') == -1
assert array.lastIndexOf(12345) == -1
Adds max() method to Object arrays.
Selects the maximum value found from the Object array using the given comparator.
comparator - a ComparatorSelects the maximum value found from the Object array using the closure to determine the correct ordering.
If the closure has two parameters it is used like a traditional Comparator. I.e. it should compare its two parameters for order, returning a negative integer, zero, or a positive integer when the first parameter is less than, equal to, or greater than the second respectively. Otherwise, the Closure is assumed to take a single parameter and return a Comparable (typically an Integer) which is then used for further comparison.
closure - a Closure used to determine the correct orderingAdds min() method to Object arrays.
Selects the minimum value found from the Object array using the given comparator.
comparator - a ComparatorSelects the minimum value found from the Object array using the closure to determine the correct ordering.
If the closure has two parameters it is used like a traditional Comparator. I.e. it should compare its two parameters for order, returning a negative integer, zero, or a positive integer when the first parameter is less than, equal to, or greater than the second respectively. Otherwise, the Closure is assumed to take a single parameter and return a Comparable (typically an Integer) which is then used for further comparison.
closure - a Closure used to determine the correct orderingCreates a new array composed of the elements of the first array minus the elements of the given Iterable.
Integer[] ints = [1, 2, 3, 1]
List<Integer> nope = [1, 3]
def result = ints - nope
assert result.class == Integer[]
assert result == new Integer[]{2}
Integer[] none = []
result = none - 123
assert result !== none
assert result.length == 0
assert result.class == Integer[]
removeMe - an Iterable of elements to removeCreates a new array composed of the elements of the first array minus the elements of the given array.
Integer[] ints = [1, 2, 3, 1]
Integer[] nope = [1, 3]
def result = ints - nope
assert result.class == Integer[]
assert result == new Integer[]{2}
Integer[] none = []
result = none - 123
assert result !== none
assert result.length == 0
assert result.class == Integer[]
removeMe - an array of elements to removeCreates a new array composed of the elements of the given array minus every occurrence the given object.
Integer[] ints = [1, 2, 3, 1]
def result = ints - 1
assert result.class == Integer[]
assert result == new Integer[]{2, 3}
Integer[] none = []
result = none - '1'
assert result !== none
assert result.length == 0
assert result.class == Integer[]
removeMe - an element to remove from the arrayReturns the index of the partition point according to the given predicate (the index of the first element of the second partition). The arr is assumed to be partitioned according to the given predicate.
def arr = [7, 15, 3, 5, 4, 12, 6] as Integer[]
assert arr.partitionPoint(0..<arr.size()) { it%2 != 0 } == 4
def arr = [1, 2, 3, 3, 4, 4, 5, 6, 7] as Integer[]
// usage case like lower_bound(cpp), bisect_left(python)
assert arr.partitionPoint(0..<arr.size()) { it < 4 } == 4
// usage case like upper_bound(cpp), bisect_right(python)
assert arr.partitionPoint(0..<arr.size()) { it <= 4 } == 6
// for all match condition
assert arr.partitionPoint(0..<arr.size()) { it <= 100 } == arr.size()
// for no match condition
assert arr.partitionPoint(0..<arr.size()) { it <= 0 } == 0
// for no match condition with range
assert arr.partitionPoint(2..<arr.size()) { it <= 0 } == 2
range - the range [l,r] to find data match the conditioncondition - the matching conditionReturns the index of the partition point according to the given predicate (the index of the first element of the second partition). The arr is assumed to be partitioned according to the given predicate.
def arr = [7, 15, 3, 5, 4, 12, 6] as Integer[]
assert arr.partitionPoint{ it%2 != 0 } == 4
def arr = [1, 2, 3, 3, 4, 4, 5, 6, 7] as Integer[]
// usage case like lower_bound(cpp), bisect_left(python)
assert arr.partitionPoint{ it < 4 } == 4
// usage case like upper_bound(cpp), bisect_right(python)
assert arr.partitionPoint{ it <= 4 } == 6
// for all match condition
assert arr.partitionPoint{ it <= 100 } == arr.size()
// for no match condition
assert arr.partitionPoint{ it <= 0 } == 0
condition - the matching conditionCreates an array containing elements from an original array plus those from a Collection.
Integer[] a = [1, 2, 3]
def result = a + [4, 5, 6]
assert result.class == Integer[]
assert result == new Integer[]{1, 2, 3, 4, 5, 6}
Number[] c = [-1, 0.9, null]
result = c + [1, 2, 3]
assert result.class == Number[]
assert result == new Number[]{-1, 0.9, null, 1, 2, 3}
result = a + [-1, 0.9, null]
assert result.class == Integer[]
assert result == new Integer[]{1, 2, 3, -1, 0, null}
// improper type arguments; Date can't be coerced to Integer
groovy.test.GroovyAssert.shouldFail(ClassCastException) { a + [new Date()] }
right - a Collection to be appendedCreates an array containing elements from an original array plus those from an Iterable.
class AbcIterable implements Iterable {
Iterator iterator() { "abc".iterator() }
}
String[] array = ['x', 'y', 'z']
def result = array + new AbcIterable()
assert result.class == String[]
assert result == new String[]{'x', 'y', 'z', 'a', 'b', 'c'}
right - an Iterable to be appendedCreates an array as a union of two arrays.
Integer[] a = [1, 2, 3]
Integer[] b = [4, 5, 6]
def result = a + b
assert result.class == Integer[]
assert result == new Integer[]{1, 2, 3, 4, 5, 6}
Number[] c = [-1, 0.9, null]
result = c + a
assert result.class == Number[]
assert result == new Number[]{-1, 0.9, null, 1, 2, 3}
result = a + c
assert result.class == Integer[]
assert result == new Integer[]{1, 2, 3, -1, 0, null}
Date[] d = [new Date()]
// improper type arguments; Date can't be coerced to Integer
groovy.test.GroovyAssert.shouldFail(ClassCastException) { a + d }
right - the right ArrayCreates an array containing elements from an original array plus an additional appended element.
Integer[] a = [1, 2, 3]
def result = a + 4
assert result.class == Integer[]
assert result == new Integer[]{1, 2, 3, 4}
result = a + 5.5d
assert result.class == Integer[]
assert result == new Integer[]{1, 2, 3, 5}
// improper type arguments; Date can't be coerced to Integer
groovy.test.GroovyAssert.shouldFail(ClassCastException) { a + new Date() }
right - the value to appendA helper method to allow arrays to be set with subscript operators.
Integer[] from = [70, 80, 90]
Integer[] nums = [1, 2, 3, 4, 5]
nums[1..3] = from
assert nums == [1, 70, 80, 90, 5]
range - the subset of the array to setsource - the source array from which new values will comeA helper method to allow arrays to be set with subscript operators. Null will be used if the source iterable has insufficient elements.
def from = [70, 80, 90]
Integer[] nums = [1, 2, 3, 4, 5]
nums[1..3] = from
assert nums == [1, 70, 80, 90, 5]
range - the subset of the array to setsource - the source array from which new values will comeCreates a new array containing items which are the same as this array but in reverse order.
Reverses the items in an array. If mutate is true, the original array is modified in place and returned. Otherwise, a new array containing the reversed items is produced.
def array = new Object[] {1,2,3}
def yarra = array.reverse(true)
assert array == 3..1
assert yarra == 3..1
yarra = array.reverse(false)
assert array == 3..1
assert yarra == 1..3
mutate - true if the array itself should be reversed in place, false if a new array should be createdIterates over each element of the array in the reverse order.
closure - a closure to which each item is passedRandomly reorders the elements of the specified array.
Integer[] array = [10, 5, 20]
def origSize = array.size()
def items = array.toList()
array.shuffle()
assert array.size() == origSize
assert items.every{ array.contains(it) }
Randomly reorders the elements of the specified array using the specified random instance as the source of randomness.
def r = new Random()
Integer[] array = [10, 5, 20]
def origSize = array.size()
def items = array.toList()
array.shuffle(r)
assert array.size() == origSize
assert items.every{ array.contains(it) }
Creates a new array containing the elements of the specified array but in a random order.
Integer[] array = [10, 5, 20]
def result = array.shuffled()
assert array !== result
assert array.length == result.length
assert array.every{ result.contains(it) }
assert array == new Integer[] {10, 5, 20}
Creates a new array containing the elements of the specified array but in a random order using the specified random instance as the source of randomness.
def r = new Random()
Integer[] array = [10, 5, 20]
def result = array.shuffled(r)
assert array !== result
assert array.length == result.length
assert array.every{ result.contains(it) }
assert array == new Integer[] {10, 5, 20}
Provides the standard Groovy size() method for an array.
Modifies this array so that its elements are in sorted order. The array items are assumed to be comparable.
Sorts the given array into sorted order. The array items are assumed to be comparable. If mutate is true, the array is sorted in place and returned. Otherwise, a new sorted array is returned and the original array remains unchanged.
def orig = ["hello","hi","Hey"] as String[]
def sorted = orig.sort(false)
assert orig == ["hello","hi","Hey"] as String[]
assert sorted == ["Hey","hello","hi"] as String[]
orig.sort(true)
assert orig == ["Hey","hello","hi"] as String[]
mutate - false will always cause a new array to be created, true will mutate the array in placeSorts the given array into sorted order using the given comparator.
comparator - a Comparator used for the comparisonSorts the elements from this array into sorted order as determined by the given comparator. If mutate is true, the array is sorted in place and returned. Otherwise, a new sorted array is returned and the original array remains unchanged.
def orig = ["hello","hi","Hey"] as String[]
def sorted = orig.sort(false, String.CASE_INSENSITIVE_ORDER)
assert orig == ["hello","hi","Hey"] as String[]
assert sorted == ["hello","Hey","hi"] as String[]
orig.sort(true, String.CASE_INSENSITIVE_ORDER)
assert orig == ["hello","Hey","hi"] as String[]
mutate - false will always cause a new array to be created, true will mutate arrays in placecomparator - a Comparator used for the comparisonSorts the elements from this array into a newly created array using the Closure to determine the correct ordering.
If the closure has two parameters it is used like a traditional Comparator. I.e. it should compare its two parameters for order, returning a negative integer, zero, or a positive integer when the first parameter is less than, equal to, or greater than the second respectively. Otherwise, the Closure is assumed to take a single parameter and return a Comparable (typically an Integer) which is then used for further comparison.
closure - a Closure used to determine the correct orderingSorts the elements from this array with index values in the given index range into a newly created array using the Closure to determine the correct ordering.
If the closure has two parameters it is used like a traditional Comparator. I.e. it should compare its two parameters for order, returning a negative integer, zero, or a positive integer when the first parameter is less than, equal to, or greater than the second respectively. Otherwise, the Closure is assumed to take a single parameter and return a Comparable (typically an Integer) which is then used for further comparison.
closure - a Closure used to determine the correct orderingSorts the elements from this array into sorted order using the Closure to determine the correct ordering. If mutate is false, a new array is returned and the original array remains unchanged. Otherwise, the original array is sorted in place and returned.
If the closure has two parameters it is used like a traditional Comparator. I.e. it should compare its two parameters for order, returning a negative integer, zero, or a positive integer when the first parameter is less than, equal to, or greater than the second respectively. Otherwise, the Closure is assumed to take a single parameter and return a Comparable (typically an Integer) which is then used for further comparison.
def orig = ["hello","hi","Hey"] as String[]
def sorted = orig.sort(false) { it.size() }
assert orig == ["hello","hi","Hey"] as String[]
assert sorted == ["hi","Hey","hello"] as String[]
orig.sort(true) { it.size() }
assert orig == ["hi","Hey","hello"] as String[]
mutate - false causes a new array to be created, true will mutate arrays in placeclosure - a Closure used to determine the correct orderingSorts the elements with index values in the given index range into sorted order using the Closure to determine the correct ordering. If mutate is false, a new array is returned and the original array remains unchanged. Otherwise, the original array is sorted in place and returned.
If the closure has two parameters it is used like a traditional Comparator. I.e. it should compare its two parameters for order, returning a negative integer, zero, or a positive integer when the first parameter is less than, equal to, or greater than the second respectively. Otherwise, the Closure is assumed to take a single parameter and return a Comparable (typically an Integer) which is then used for further comparison.
// an array with some odd then even numbers
Integer[] nums = [5, 9, 1, 7, 3, 4, 8, 6, 0, 2]
// sort odds ascending, evens descending
assert nums.sort(0..4, false) { it }.sort(5..9, false) { -it }
== [1, 3, 5, 7, 9, 8, 6, 4, 2, 0]
// sort odds descending, evens descending
assert nums.sort(0..<5, false) { -it }.sort(4<..<10, false) { -it }
== [9, 7, 5, 3, 1, 8, 6, 4, 2, 0]
// sort odds descending, evens ascending
assert nums.sort(0..<5, false) { -it }.sort(5..-1, false) { it }
== [9, 7, 5, 3, 1, 0, 2, 4, 6, 8]
// leave first and last numbers, sort remaining odds ascending, remaining evens descending
assert nums.sort(1..4, false) { it }.sort(5..-2, false) { -it }
== [5, 1, 3, 7, 9, 8, 6, 4, 0, 2]
// leave first and last numbers, sort remaining odds descending, remaining evens ascending
assert nums.sort(1..4, false) { -it }.sort(5..-2, false) { it }
== [5, 9, 7, 3, 1, 0, 4, 6, 8, 2]
// leave first and last odds and evens, sort remaining odds ascending, remaining evens descending
assert nums.sort(0<..<4, false) { it }.sort(5<..<9, false) { -it }
== [5, 1, 7, 9, 3, 4, 8, 6, 0, 2]
// leave first and last odds and evens, sort remaining odds descending, remaining evens ascending
assert nums.sort(0<..<4, false) { -it }.sort(5<..<-1, false) { it }
== [5, 9, 7, 1, 3, 4, 0, 6, 8, 2]
range - the inclusive range of index values over which to sortmutate - false causes a new array to be created, true will mutate arrays in placeclosure - a Closure used to determine the correct orderingSplits all items into two collections based on the closure condition. The first list contains all items which match the closure expression. The second list all those that don't.
closure - a closure conditionReturns a sequential Stream with the specified array as its source.
self - The array, assumed to be unmodified during useStream for the arraySums the items in an array. This is equivalent to invoking the "plus" method on all items in the array.
Sums the items in an array, adding the result to some initial value.
initialValue - the items in the array will be summed to this initial value Sums the result of applying a closure to each item of an array.
array.sum(closure) is equivalent to:
array.collect(closure).sum().
closure - a single parameter closure that returns a (typically) numeric value. Sums the result of applying a closure to each item of an array to some initial value.
array.sum(initVal, closure) is equivalent to:
array.collect(closure).sum(initVal).
closure - a single parameter closure that returns a (typically) numeric value.initialValue - the closure results will be summed to this initial valueSwaps two elements at the specified positions.
Example:
assert (["a", "c", "b", "d"] as String[]) == (["a", "b", "c", "d"] as String[]).swap(1, 2)
i - a positionj - a positionReturns the items from the array excluding the first item.
String[] strings = ["a", "b", "c"]
def result = strings.tail()
assert result.class.componentType == String
String[] expected = ["b", "c"]
assert result == expected
Returns the first num elements from the head of this array.
String[] strings = [ 'a', 'b', 'c' ]
assert strings.take( 0 ) == [] as String[]
assert strings.take( 2 ) == [ 'a', 'b' ] as String[]
assert strings.take( 5 ) == [ 'a', 'b', 'c' ] as String[]
num - the number of elements to take from this arraynum elements of this array,
or else the whole array if it has less than num elements. Returns the last num elements from the tail of this array.
String[] strings = [ 'a', 'b', 'c' ]
assert strings.takeRight( 0 ) == [] as String[]
assert strings.takeRight( 2 ) == [ 'b', 'c' ] as String[]
assert strings.takeRight( 5 ) == [ 'a', 'b', 'c' ] as String[]
num - the number of elements to take from this arraynum elements of this array,
or else the whole array if it has less than num elements.Returns the longest prefix of this array where each element passed to the given closure evaluates to true.
def nums = [ 1, 3, 2 ] as Integer[]
assert nums.takeWhile{ it < 1 } == [] as Integer[]
assert nums.takeWhile{ it < 3 } == [ 1 ] as Integer[]
assert nums.takeWhile{ it < 4 } == [ 1, 3, 2 ] as Integer[]
condition - the closure that must evaluate to true to
continue taking elementsConverts this array to a List of the same size, with each element added to the list.
Converts this array to a Set, with each unique element added to the set.
Returns a sorted version of the given array using the supplied comparator.
Returns a sorted version of the given array using the supplied comparator to determine the resulting order.
def sumDigitsComparator = [compare: { num1, num2 -> num1.toString().toList()*.toInteger().sum() <=> num2.toString().toList()*.toInteger().sum() }] as Comparator
Integer[] nums = [9, 44, 222, 7000]
def result = nums.toSorted(sumDigitsComparator)
assert result instanceof Integer[]
assert result == [222, 7000, 44, 9]
comparator - a Comparator used for the comparisonSorts the elements from this array into a newly created array using the Closure to determine the correct ordering.
If the closure has two parameters it is used like a traditional Comparator. I.e. it should compare its two parameters for order, returning a negative integer, zero, or a positive integer when the first parameter is less than, equal to, or greater than the second respectively. Otherwise, the Closure is assumed to take a single parameter and return a Comparable (typically an Integer) which is then used for further comparison.
closure - a Closure used to determine the correct orderingCreates a spreadable map from this array.
Returns the string representation of the given array.
Returns a new Array containing the items from the original Array but with duplicates removed using the natural ordering of the items in the array.
String[] letters = ['c', 'a', 't', 's', 'a', 't', 'h', 'a', 't']
String[] expected = ['c', 'a', 't', 's', 'h']
def result = letters.toUnique()
assert result == expected
assert result.class.componentType == String
Returns a new Array containing the items from the original Array but with duplicates removed with the supplied comparator determining which items are unique.
String[] letters = ['c', 'a', 't', 's', 'A', 't', 'h', 'a', 'T']
String[] lower = ['c', 'a', 't', 's', 'h']
class LowerComparator implements Comparator {
int compare(a, b) { a.toLowerCase() <=> b.toLowerCase() }
}
assert letters.toUnique(new LowerComparator()) == lower
comparator - a Comparator used to determine unique (equal) items
If null, the Comparable natural ordering of the elements will be used.Returns a new Array containing the items from the original Array but with duplicates removed with the supplied closure determining which items are unique.
String[] letters = ['c', 'a', 't', 's', 'A', 't', 'h', 'a', 'T']
String[] expected = ['c', 'a', 't', 's', 'h']
assert letters.toUnique{ p1, p2 -> p1.toLowerCase() <=> p2.toLowerCase() } == expected
assert letters.toUnique{ it.toLowerCase() } == expected
closure - a Closure used to determine unique itemsCreates an object array containing elements from an original array plus those from a Collection. This is similar to Object but always return an Object array and so might be more applicable when adding heterogeneous arrays.
Integer[] a = [1, 2, 3]
def result = a.union(['foo', 'bar'])
assert result.class == Object[]
assert result == new Object[]{1, 2, 3, 'foo', 'bar'}
right - a Collection to be appendedCreates an Object array containing elements from an original array plus those from an Iterable. This is similar to Object but always return an Object array and so might be more applicable when adding heterogeneous arrays.
class AbcIterable implements Iterable {
Iterator iterator() { "abc".iterator() }
}
String[] array = ['x', 'y', 'z']
def result = array.union(new AbcIterable())
assert result.class == Object[]
assert result == new Object[]{'x', 'y', 'z', 'a', 'b', 'c'}
right - an Iterable to be appendedCreates an Object array as a union of two arrays. This is similar to Object but always return an Object array and so might be more applicable when adding heterogeneous arrays.
Integer[] a = [1, 2, 3]
String[] b = ['foo', 'bar']
def result = a.union(b)
assert result.class == Object[]
assert result == new Object[]{1, 2, 3, 'foo', 'bar'}
right - the right ArrayCreates an Object array containing elements from an original array plus an additional appended element. This is similar to Object but always return an Object array and so might be more applicable when adding heterogeneous arrays.
Integer[] a = [1, 2, 3]
def result = a.union('foo')
assert result.class == Object[]
assert result == new Object[]{1, 2, 3, 'foo'}
right - the value to appendA variant of withCollectedKeys for arrays.
keyTransform - a function for transforming array elements into valuesA variant of withCollectedKeys for arrays.
collector - the Map into which the transformed entries are putkeyTransform - a function for transforming array elements into valuesA variant of withCollectedValues for arrays.
valueTransform - a function for transforming array elements into valuesA variant of withCollectedValues for arrays.
collector - the Map into which the transformed entries are putvalueTransform - a function for transforming array elements into valuesZips an object array with indices in (value, index) order.
Example usage:
String[] letters = ['a', 'z']
assert [['a', 0], ['z', 1]] == letters.withIndex()
Zips an object array with indices in (value, index) order starting from a given index.
Example usage:
String[] letters = ['a', 'z']
assert [['a', 5], ['z', 6]] == letters.withIndex(5)
assert ["5: a", "6: z"] == letters.withIndex(5).collect { n, idx -> "$idx: $n" }
offset - an index to start from