Package io.micronaut.core.util
Class CollectionUtils
- java.lang.Object
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- io.micronaut.core.util.CollectionUtils
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public class CollectionUtils extends java.lang.ObjectUtility methods for working with
.Collectiontypes- Since:
- 1.0
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Constructor Summary
Constructors Constructor Description CollectionUtils()
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Method Summary
All Methods Static Methods Concrete Methods Modifier and Type Method Description static <T> java.util.Optional<java.lang.Iterable<T>>convertCollection(java.lang.Class<? extends java.lang.Iterable<T>> iterableType, java.util.Collection<T> collection)Attempts to convert a collection to the given iterabable typestatic <T> java.lang.Iterable<T>enumerationToIterable(java.util.Enumeration<T> enumeration)Convert anEnumerationto aIterable.static <T> java.util.Set<T>enumerationToSet(java.util.Enumeration<T> enumeration)Convert anEnumerationto aSet.static booleanisEmpty(java.util.Collection collection)Null safe empty check.static booleanisEmpty(java.util.Map map)Null safe empty check.static booleanisIterableOrMap(java.lang.Class<?> type)Is the given type an iterable or map type.static booleanisNotEmpty(java.util.Collection collection)Null safe not empty check.static booleanisNotEmpty(java.util.Map map)Null safe not empty check.static <T> java.util.List<T>iterableToList(java.lang.Iterable<T> iterable)Converts anIterableto aList.static <T> java.util.Set<T>iterableToSet(java.lang.Iterable<T> iterable)Converts anIterableto aSet.static <T> java.util.Set<T>iteratorToSet(java.util.Iterator<T> iterator)Convert anIteratorto aSet.static <T> Tlast(java.util.Collection<T> collection)Returns the last element of a collection.static java.util.MapmapOf(java.lang.Object... values)Create aLinkedHashMapfrom an array of values.static <T> java.util.Set<T>setOf(T... objects)Creates a set of the given objects.static java.lang.StringtoString(java.lang.Iterable<?> iterable)Produce a string representation of the given iterable.static java.lang.StringtoString(java.lang.String delimiter, java.lang.Iterable<?> iterable)Produce a string representation of the given iterable.static <T> java.util.List<T>unmodifiableList(java.util.List<T> list)Null safe version ofCollections.unmodifiableList(List).
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Method Detail
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isIterableOrMap
public static boolean isIterableOrMap(java.lang.Class<?> type)
Is the given type an iterable or map type.- Parameters:
type- The type- Returns:
- True if it is iterable or map
- Since:
- 2.0.0
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isEmpty
public static boolean isEmpty(@Nullable java.util.Map map)
Null safe empty check.- Parameters:
map- The map- Returns:
- True if it is empty or null
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isNotEmpty
public static boolean isNotEmpty(@Nullable java.util.Map map)
Null safe not empty check.- Parameters:
map- The map- Returns:
- True if it is not null and not empty
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isEmpty
public static boolean isEmpty(@Nullable java.util.Collection collection)
Null safe empty check.- Parameters:
collection- The collection- Returns:
- True if it is empty or null
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isNotEmpty
public static boolean isNotEmpty(@Nullable java.util.Collection collection)
Null safe not empty check.- Parameters:
collection- The collection- Returns:
- True if it is not null and not empty
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convertCollection
public static <T> java.util.Optional<java.lang.Iterable<T>> convertCollection(java.lang.Class<? extends java.lang.Iterable<T>> iterableType, java.util.Collection<T> collection)Attempts to convert a collection to the given iterabable type
.- Type Parameters:
T- The collection generic type- Parameters:
iterableType- The iterable typecollection- The collection- Returns:
- An
Optionalof the converted type
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mapOf
public static java.util.Map mapOf(java.lang.Object... values)
Create aLinkedHashMapfrom an array of values.- Parameters:
values- The values- Returns:
- The created map
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iteratorToSet
public static <T> java.util.Set<T> iteratorToSet(java.util.Iterator<T> iterator)
Convert anIteratorto aSet.- Type Parameters:
T- The type- Parameters:
iterator- The iterator- Returns:
- The set
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enumerationToSet
public static <T> java.util.Set<T> enumerationToSet(java.util.Enumeration<T> enumeration)
Convert anEnumerationto aSet.- Type Parameters:
T- The type- Parameters:
enumeration- The iterator- Returns:
- The set
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enumerationToIterable
@NonNull public static <T> java.lang.Iterable<T> enumerationToIterable(@Nullable java.util.Enumeration<T> enumeration)
Convert anEnumerationto aIterable.- Type Parameters:
T- The type- Parameters:
enumeration- The iterator- Returns:
- The set
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setOf
public static <T> java.util.Set<T> setOf(T... objects)
Creates a set of the given objects.- Type Parameters:
T- The type- Parameters:
objects- The objects- Returns:
- The set
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toString
public static java.lang.String toString(java.lang.Iterable<?> iterable)
Produce a string representation of the given iterable.- Parameters:
iterable- The iterable- Returns:
- The string representation
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toString
public static java.lang.String toString(java.lang.String delimiter, java.lang.Iterable<?> iterable)Produce a string representation of the given iterable.- Parameters:
delimiter- The delimiteriterable- The iterable- Returns:
- The string representation
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iterableToList
public static <T> java.util.List<T> iterableToList(java.lang.Iterable<T> iterable)
Converts anIterableto aList.- Type Parameters:
T- The generic type- Parameters:
iterable- The iterable- Returns:
- The list
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iterableToSet
public static <T> java.util.Set<T> iterableToSet(java.lang.Iterable<T> iterable)
Converts anIterableto aSet.- Type Parameters:
T- The generic type- Parameters:
iterable- The iterable- Returns:
- The set
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unmodifiableList
@NonNull public static <T> java.util.List<T> unmodifiableList(@Nullable java.util.List<T> list)
Null safe version ofCollections.unmodifiableList(List).- Type Parameters:
T- The generic type- Parameters:
list- The list- Returns:
- A non-null unmodifiable list
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