Package org.elasticsearch.common.util
Class CollectionUtils
java.lang.Object
org.elasticsearch.common.util.CollectionUtils
Collections-related utility methods.
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Constructor Summary
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Method Summary
Modifier and TypeMethodDescriptionstatic <E> List<E>
appendToCopy
(Collection<E> collection, E element) Creates a copy of the given collection with the given element appended.static <E> ArrayList<E>
arrayAsArrayList
(E... elements) static <E> ArrayList<E>
asArrayList
(E first, E... other) static <E> ArrayList<E>
asArrayList
(E first, E second, E... other) static <E> List<E>
concatLists
(List<E> listA, List<E> listB) static <R,
T> Map<R, T> Returns an unmodifiable copy of the given map.eagerPartition
(List<E> list, int size) static void
ensureNoSelfReferences
(Object value, String messageHint) Deeply inspects a Map, Iterable, or Object array looking for references back to itself.static boolean
Checks if the given array contains any elements.static <E> ArrayList<E>
iterableAsArrayList
(Iterable<? extends E> elements) static <E> ArrayList<E>
newSingletonArrayList
(E element) static <T> List<T>
Return a rotated view of the given list with the given distance.static void
sort
(com.carrotsearch.hppc.ObjectArrayList<byte[]> array) static void
sort
(org.apache.lucene.util.BytesRefArray bytes, int[] indices) static void
sortAndDedup
(com.carrotsearch.hppc.ObjectArrayList<byte[]> array) static int
sortAndDedup
(org.apache.lucene.util.BytesRefArray bytes, int[] indices) static int[]
toArray
(Collection<Integer> ints) static <E> List<E>
wrapUnmodifiableOrEmptySingleton
(List<E> list)
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Constructor Details
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CollectionUtils
public CollectionUtils()
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Method Details
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isEmpty
Checks if the given array contains any elements.- Parameters:
array
- The array to check- Returns:
- false if the array contains an element, true if not or the array is null.
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rotate
Return a rotated view of the given list with the given distance. -
sortAndDedup
public static void sortAndDedup(com.carrotsearch.hppc.ObjectArrayList<byte[]> array) -
sort
public static void sort(com.carrotsearch.hppc.ObjectArrayList<byte[]> array) -
toArray
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ensureNoSelfReferences
Deeply inspects a Map, Iterable, or Object array looking for references back to itself.- Parameters:
value
- The object to evaluate looking for self referencesmessageHint
- A string to be included in the exception message if the call fails, to provide more context to the handler of the exception- Throws:
IllegalArgumentException
- if a self-reference is found
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copyMap
Returns an unmodifiable copy of the given map.- Parameters:
map
- Map to copy- Returns:
- unmodifiable copy of the map
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sort
public static void sort(org.apache.lucene.util.BytesRefArray bytes, int[] indices) -
sortAndDedup
public static int sortAndDedup(org.apache.lucene.util.BytesRefArray bytes, int[] indices) -
iterableAsArrayList
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arrayAsArrayList
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asArrayList
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asArrayList
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appendToCopy
Creates a copy of the given collection with the given element appended.- Parameters:
collection
- collection to copyelement
- element to append
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newSingletonArrayList
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eagerPartition
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concatLists
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wrapUnmodifiableOrEmptySingleton
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