Package Summary  Overview Summary

class:Set [CHANGED]

  • Type Parameters:
    E - the type of elements maintained by this set
    All Superinterfaces:
    Collection<E>, java.lang.Iterable<E>
    All Known Subinterfaces:
    NavigableSet<E>, SortedSet<E>
    All Known Implementing Classes:
    AbstractSet, EnumSet, HashSet, LinkedHashSet, TreeSet


    public interface Set<E>
    extends Collection<E>
    A collection that contains no duplicate elements. More formally, sets contain no pair of elements e1 and e2 such that e1.equals(e2), and at most one null element. As implied by its name, this interface models the mathematical set abstraction.

    The Set interface places additional stipulations, beyond those inherited from the Collection interface, on the contracts of all constructors and on the contracts of the add, equals and hashCode methods. Declarations for other inherited methods are also included here for convenience. (The specifications accompanying these declarations have been tailored to the Set interface, but they do not contain any additional stipulations.)

    The additional stipulation on constructors is, not surprisingly, that all constructors must create a set that contains no duplicate elements (as defined above).

    Note: Great care must be exercised if mutable objects are used as set elements. The behavior of a set is not specified if the value of an object is changed in a manner that affects equals comparisons while the object is an element in the set. A special case of this prohibition is that it is not permissible for a set to contain itself as an element.

    Some set implementations have restrictions on the elements that they may contain. For example, some implementations prohibit null elements, and some have restrictions on the types of their elements. Attempting to add an ineligible element throws an unchecked exception, typically NullPointerException or ClassCastException. Attempting to query the presence of an ineligible element may throw an exception, or it may simply return false; some implementations will exhibit the former behavior and some will exhibit the latter. More generally, attempting an operation on an ineligible element whose completion would not result in the insertion of an ineligible element into the set may throw an exception or it may succeed, at the option of the implementation. Such exceptions are marked as "optional" in the specification for this interface.

    Immutable Set Static Factory Methods

    The Set.of() static factory methods provide a convenient way to create immutable sets. The Set instances created by these methods have the following characteristics:

    • They cannot be modified. Attempts to modify them result in an UnsupportedOperationException.
    • They are truly immutable only if the contained elements are themselves immutable. If an element is mutated, the behavior of the set is unspecified.
    • They disallow null elements. Attempts to create them with null elements result in NullPointerException.
    • They are serializable if all elements are serializable.
    • They reject duplicate elements at creation time. Duplicate elements passed to a static factory method result in IllegalArgumentException.

    This interface is a member of the Java Collections Framework .

    Since:
    1.2
    See Also:
    Collection, List, SortedSet, HashSet, TreeSet, AbstractSet, Collections.singleton(java.lang.Object), Collections.EMPTY_SET
  • Type Parameters:
    E - the type of elements maintained by this set
    All Superinterfaces:
    Collection<E>, java.lang.Iterable<E>
    All Known Subinterfaces:
    NavigableSet<E>, SortedSet<E>
    All Known Implementing Classes:
    AbstractSet, EnumSet, HashSet, LinkedHashSet, TreeSet


    public interface Set<E>
    extends Collection<E>
    A collection that contains no duplicate elements. More formally, sets contain no pair of elements e1 and e2 such that e1.equals(e2), and at most one null element. As implied by its name, this interface models the mathematical set abstraction.

    The Set interface places additional stipulations, beyond those inherited from the Collection interface, on the contracts of all constructors and on the contracts of the add, equals and hashCode methods. Declarations for other inherited methods are also included here for convenience. (The specifications accompanying these declarations have been tailored to the Set interface, but they do not contain any additional stipulations.)

    The additional stipulation on constructors is, not surprisingly, that all constructors must create a set that contains no duplicate elements (as defined above).

    Note: Great care must be exercised if mutable objects are used as set elements. The behavior of a set is not specified if the value of an object is changed in a manner that affects equals comparisons while the object is an element in the set. A special case of this prohibition is that it is not permissible for a set to contain itself as an element.

    Some set implementations have restrictions on the elements that they may contain. For example, some implementations prohibit null elements, and some have restrictions on the types of their elements. Attempting to add an ineligible element throws an unchecked exception, typically NullPointerException or ClassCastException. Attempting to query the presence of an ineligible element may throw an exception, or it may simply return false; some implementations will exhibit the former behavior and some will exhibit the latter. More generally, attempting an operation on an ineligible element whose completion would not result in the insertion of an ineligible element into the set may throw an exception or it may succeed, at the option of the implementation. Such exceptions are marked as "optional" in the specification for this interface.

    This interface is a member of the Java Collections Framework .

    Since:
    1.2
    See Also:
    Collection, List, SortedSet, HashSet, TreeSet, AbstractSet, Collections.singleton(java.lang.Object), Collections.EMPTY_SET
  • Type Parameters:
    E - the type of elements maintained by this set
    All Superinterfaces:
    Collection<E>, java.lang.Iterable<E>
    All Known Subinterfaces:
    NavigableSet<E>, SortedSet<E>
    All Known Implementing Classes:
    AbstractSet, EnumSet, HashSet, LinkedHashSet, TreeSet


    public interface Set<E>
    extends Collection<E>
    A collection that contains no duplicate elements. More formally, sets contain no pair of elements e1 and e2 such that e1.equals(e2), and at most one null element. As implied by its name, this interface models the mathematical set abstraction.

    The Set interface places additional stipulations, beyond those inherited from the Collection interface, on the contracts of all constructors and on the contracts of the add, equals and hashCode methods. Declarations for other inherited methods are also included here for convenience. (The specifications accompanying these declarations have been tailored to the Set interface, but they do not contain any additional stipulations.)

    The additional stipulation on constructors is, not surprisingly, that all constructors must create a set that contains no duplicate elements (as defined above).

    Note: Great care must be exercised if mutable objects are used as set elements. The behavior of a set is not specified if the value of an object is changed in a manner that affects equals comparisons while the object is an element in the set. A special case of this prohibition is that it is not permissible for a set to contain itself as an element.

    Some set implementations have restrictions on the elements that they may contain. For example, some implementations prohibit null elements, and some have restrictions on the types of their elements. Attempting to add an ineligible element throws an unchecked exception, typically NullPointerException or ClassCastException. Attempting to query the presence of an ineligible element may throw an exception, or it may simply return false; some implementations will exhibit the former behavior and some will exhibit the latter. More generally, attempting an operation on an ineligible element whose completion would not result in the insertion of an ineligible element into the set may throw an exception or it may succeed, at the option of the implementation. Such exceptions are marked as "optional" in the specification for this interface.

    Immutable Set Static Factory Methods

    The Set.of() static factory methods provide a convenient way to create immutable sets. The Set instances created by these methods have the following characteristics:

    • They cannot be modified. Attempts to modify them result in an UnsupportedOperationException.
    • They are truly immutable only if the contained elements are themselves immutable. If an element is mutated, the behavior of the set is unspecified.
    • They disallow null elements. Attempts to create them with null elements result in NullPointerException.
    • They are serializable if all elements are serializable.
    • They reject duplicate elements at creation time. Duplicate elements passed to a static factory method result in IllegalArgumentException.

    This interface is a member of the Java Collections Framework .

    Since:
    1.2
    See Also:
    Collection, List, SortedSet, HashSet, TreeSet, AbstractSet, Collections.singleton(java.lang.Object), Collections.EMPTY_SET

method:size() [NONE]

  • size

    int size()
    Returns the number of elements in this set (its cardinality). If this set contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE.
    Specified by:
    size in interface Collection<E>
    Returns:
    the number of elements in this set (its cardinality)

method:isEmpty() [NONE]

  • isEmpty

    boolean isEmpty()
    Returns true if this set contains no elements.
    Specified by:
    isEmpty in interface Collection<E>
    Returns:
    true if this set contains no elements

method:contains(java.lang.Object) [NONE]

  • contains

    boolean contains(java.lang.Object o)
    Returns true if this set contains the specified element. More formally, returns true if and only if this set contains an element e such that Objects.equals(o, e) .
    Specified by:
    contains in interface Collection<E>
    Parameters:
    o - element whose presence in this set is to be tested
    Returns:
    true if this set contains the specified element
    Throws:
    java.lang.ClassCastException - if the type of the specified element is incompatible with this set (optional)
    java.lang.NullPointerException - if the specified element is null and this set does not permit null elements (optional)

method:iterator() [NONE]

  • iterator

    Iterator<E> iterator()
    Returns an iterator over the elements in this set. The elements are returned in no particular order (unless this set is an instance of some class that provides a guarantee).
    Specified by:
    iterator in interface Collection<E>
    Specified by:
    iterator in interface java.lang.Iterable<E>
    Returns:
    an iterator over the elements in this set

method:toArray() [NONE]

  • toArray

    java.lang.Object[] toArray()
    Returns an array containing all of the elements in this set. If this set makes any guarantees as to what order its elements are returned by its iterator, this method must return the elements in the same order.

    The returned array will be "safe" in that no references to it are maintained by this set. (In other words, this method must allocate a new array even if this set is backed by an array). The caller is thus free to modify the returned array.

    This method acts as bridge between array-based and collection-based APIs.

    Specified by:
    toArray in interface Collection<E>
    Returns:
    an array containing all the elements in this set

method:toArray(T[]) [NONE]

  • toArray

    <T> T[] toArray(T[] a)
    Returns an array containing all of the elements in this set; the runtime type of the returned array is that of the specified array. If the set fits in the specified array, it is returned therein. Otherwise, a new array is allocated with the runtime type of the specified array and the size of this set.

    If this set fits in the specified array with room to spare (i.e., the array has more elements than this set), the element in the array immediately following the end of the set is set to null. (This is useful in determining the length of this set only if the caller knows that this set does not contain any null elements.)

    If this set makes any guarantees as to what order its elements are returned by its iterator, this method must return the elements in the same order.

    Like the toArray() method, this method acts as bridge between array-based and collection-based APIs. Further, this method allows precise control over the runtime type of the output array, and may, under certain circumstances, be used to save allocation costs.

    Suppose x is a set known to contain only strings. The following code can be used to dump the set into a newly allocated array of String:

         String[] y = x.toArray(new String[0]);
    Note that toArray(new Object[0]) is identical in function to toArray().

    Specified by:
    toArray in interface Collection<E>
    Type Parameters:
    T - the runtime type of the array to contain the collection
    Parameters:
    a - the array into which the elements of this set are to be stored, if it is big enough; otherwise, a new array of the same runtime type is allocated for this purpose.
    Returns:
    an array containing all the elements in this set
    Throws:
    java.lang.ArrayStoreException - if the runtime type of the specified array is not a supertype of the runtime type of every element in this set
    java.lang.NullPointerException - if the specified array is null

method:add(E) [NONE]

  • add

    boolean add(E e)
    Adds the specified element to this set if it is not already present (optional operation). More formally, adds the specified element e to this set if the set contains no element e2 such that Objects.equals(e, e2) . If this set already contains the element, the call leaves the set unchanged and returns false. In combination with the restriction on constructors, this ensures that sets never contain duplicate elements.

    The stipulation above does not imply that sets must accept all elements; sets may refuse to add any particular element, including null, and throw an exception, as described in the specification for Collection.add. Individual set implementations should clearly document any restrictions on the elements that they may contain.

    Specified by:
    add in interface Collection<E>
    Parameters:
    e - element to be added to this set
    Returns:
    true if this set did not already contain the specified element
    Throws:
    java.lang.UnsupportedOperationException - if the add operation is not supported by this set
    java.lang.ClassCastException - if the class of the specified element prevents it from being added to this set
    java.lang.NullPointerException - if the specified element is null and this set does not permit null elements
    java.lang.IllegalArgumentException - if some property of the specified element prevents it from being added to this set

method:remove(java.lang.Object) [NONE]

  • remove

    boolean remove(java.lang.Object o)
    Removes the specified element from this set if it is present (optional operation). More formally, removes an element e such that Objects.equals(o, e) , if this set contains such an element. Returns true if this set contained the element (or equivalently, if this set changed as a result of the call). (This set will not contain the element once the call returns.)
    Specified by:
    remove in interface Collection<E>
    Parameters:
    o - object to be removed from this set, if present
    Returns:
    true if this set contained the specified element
    Throws:
    java.lang.ClassCastException - if the type of the specified element is incompatible with this set (optional)
    java.lang.NullPointerException - if the specified element is null and this set does not permit null elements (optional)
    java.lang.UnsupportedOperationException - if the remove operation is not supported by this set

method:containsAll(java.util.Collection) [NONE]

  • containsAll

    boolean containsAll(Collection<?> c)
    Returns true if this set contains all of the elements of the specified collection. If the specified collection is also a set, this method returns true if it is a subset of this set.
    Specified by:
    containsAll in interface Collection<E>
    Parameters:
    c - collection to be checked for containment in this set
    Returns:
    true if this set contains all of the elements of the specified collection
    Throws:
    java.lang.ClassCastException - if the types of one or more elements in the specified collection are incompatible with this set (optional)
    java.lang.NullPointerException - if the specified collection contains one or more null elements and this set does not permit null elements (optional), or if the specified collection is null
    See Also:
    contains(Object)

method:addAll(java.util.Collection) [NONE]

  • addAll

    boolean addAll(Collection<? extends E> c)
    Adds all of the elements in the specified collection to this set if they're not already present (optional operation). If the specified collection is also a set, the addAll operation effectively modifies this set so that its value is the union of the two sets. The behavior of this operation is undefined if the specified collection is modified while the operation is in progress.
    Specified by:
    addAll in interface Collection<E>
    Parameters:
    c - collection containing elements to be added to this set
    Returns:
    true if this set changed as a result of the call
    Throws:
    java.lang.UnsupportedOperationException - if the addAll operation is not supported by this set
    java.lang.ClassCastException - if the class of an element of the specified collection prevents it from being added to this set
    java.lang.NullPointerException - if the specified collection contains one or more null elements and this set does not permit null elements, or if the specified collection is null
    java.lang.IllegalArgumentException - if some property of an element of the specified collection prevents it from being added to this set
    See Also:
    add(Object)

method:retainAll(java.util.Collection) [NONE]

  • retainAll

    boolean retainAll(Collection<?> c)
    Retains only the elements in this set that are contained in the specified collection (optional operation). In other words, removes from this set all of its elements that are not contained in the specified collection. If the specified collection is also a set, this operation effectively modifies this set so that its value is the intersection of the two sets.
    Specified by:
    retainAll in interface Collection<E>
    Parameters:
    c - collection containing elements to be retained in this set
    Returns:
    true if this set changed as a result of the call
    Throws:
    java.lang.UnsupportedOperationException - if the retainAll operation is not supported by this set
    java.lang.ClassCastException - if the class of an element of this set is incompatible with the specified collection (optional)
    java.lang.NullPointerException - if this set contains a null element and the specified collection does not permit null elements (optional), or if the specified collection is null
    See Also:
    remove(Object)

method:removeAll(java.util.Collection) [NONE]

  • removeAll

    boolean removeAll(Collection<?> c)
    Removes from this set all of its elements that are contained in the specified collection (optional operation). If the specified collection is also a set, this operation effectively modifies this set so that its value is the asymmetric set difference of the two sets.
    Specified by:
    removeAll in interface Collection<E>
    Parameters:
    c - collection containing elements to be removed from this set
    Returns:
    true if this set changed as a result of the call
    Throws:
    java.lang.UnsupportedOperationException - if the removeAll operation is not supported by this set
    java.lang.ClassCastException - if the class of an element of this set is incompatible with the specified collection (optional)
    java.lang.NullPointerException - if this set contains a null element and the specified collection does not permit null elements (optional), or if the specified collection is null
    See Also:
    remove(Object), contains(Object)

method:clear() [NONE]

  • clear

    void clear()
    Removes all of the elements from this set (optional operation). The set will be empty after this call returns.
    Specified by:
    clear in interface Collection<E>
    Throws:
    java.lang.UnsupportedOperationException - if the clear method is not supported by this set

method:equals(java.lang.Object) [NONE]

  • equals

    boolean equals(java.lang.Object o)
    Compares the specified object with this set for equality. Returns true if the specified object is also a set, the two sets have the same size, and every member of the specified set is contained in this set (or equivalently, every member of this set is contained in the specified set). This definition ensures that the equals method works properly across different implementations of the set interface.
    Specified by:
    equals in interface Collection<E>
    Overrides:
    equals in class java.lang.Object
    Parameters:
    o - object to be compared for equality with this set
    Returns:
    true if the specified object is equal to this set
    See Also:
    Object.hashCode(), HashMap

method:hashCode() [NONE]

  • hashCode

    int hashCode()
    Returns the hash code value for this set. The hash code of a set is defined to be the sum of the hash codes of the elements in the set, where the hash code of a null element is defined to be zero. This ensures that s1.equals(s2) implies that s1.hashCode()==s2.hashCode() for any two sets s1 and s2, as required by the general contract of Object.hashCode().
    Specified by:
    hashCode in interface Collection<E>
    Overrides:
    hashCode in class java.lang.Object
    Returns:
    the hash code value for this set
    See Also:
    Object.equals(Object), equals(Object)

method:spliterator() [NONE]

  • spliterator

    default Spliterator<E> spliterator()
    Creates a Spliterator over the elements in this set.

    The Spliterator reports Spliterator.DISTINCT. Implementations should document the reporting of additional characteristic values.

    Specified by:
    spliterator in interface Collection<E>
    Specified by:
    spliterator in interface java.lang.Iterable<E>
    Implementation Requirements:
    The default implementation creates a late-binding spliterator from the set's Iterator. The spliterator inherits the fail-fast properties of the set's iterator.

    The created Spliterator additionally reports Spliterator.SIZED.

    Implementation Note:
    The created Spliterator additionally reports Spliterator.SUBSIZED.
    Returns:
    a Spliterator over the elements in this set
    Since:
    1.8

method:of() [ADDED]

  • of

    static <E> Set<E> of()
    
    Creates an immutable set containing zero elements. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Returns:
    the newly created set
    Since:
    9

method:of(E) [ADDED]

  • of

    static <E> Set<E> of(E e1)
    
    Creates an immutable set containing one element. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Parameters:
    e1 - the single set element
    Returns:
    the newly created set
    Throws:
    java.lang.NullPointerException - if the element is null
    Since:
    9

method:of(E, E) [ADDED]

  • of

    static <E> Set<E> of(E e1,
                         E e2)
    
    Creates an immutable set containing two elements. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Parameters:
    e1 - the first set element
    e2 - the second set element
    Returns:
    the newly created set
    Throws:
    java.lang.IllegalArgumentException - if the elements are duplicates
    java.lang.NullPointerException - if an element is null
    Since:
    9

method:of(E, E, E) [ADDED]

  • of

    static <E> Set<E> of(E e1,
                         E e2,
                         E e3)
    
    Creates an immutable set containing three elements. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Parameters:
    e1 - the first set element
    e2 - the second set element
    e3 - the third set element
    Returns:
    the newly created set
    Throws:
    java.lang.IllegalArgumentException - if there are any duplicate elements
    java.lang.NullPointerException - if an element is null
    Since:
    9

method:of(E, E, E, E) [ADDED]

  • of

    static <E> Set<E> of(E e1,
                         E e2,
                         E e3,
                         E e4)
    
    Creates an immutable set containing four elements. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Parameters:
    e1 - the first set element
    e2 - the second set element
    e3 - the third set element
    e4 - the fourth set element
    Returns:
    the newly created set
    Throws:
    java.lang.IllegalArgumentException - if there are any duplicate elements
    java.lang.NullPointerException - if an element is null
    Since:
    9

method:of(E, E, E, E, E) [ADDED]

  • of

    static <E> Set<E> of(E e1,
                         E e2,
                         E e3,
                         E e4,
                         E e5)
    
    Creates an immutable set containing five elements. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Parameters:
    e1 - the first set element
    e2 - the second set element
    e3 - the third set element
    e4 - the fourth set element
    e5 - the fifth set element
    Returns:
    the newly created set
    Throws:
    java.lang.IllegalArgumentException - if there are any duplicate elements
    java.lang.NullPointerException - if an element is null
    Since:
    9

method:of(E, E, E, E, E, E) [ADDED]

  • of

    static <E> Set<E> of(E e1,
                         E e2,
                         E e3,
                         E e4,
                         E e5,
                         E e6)
    
    Creates an immutable set containing six elements. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Parameters:
    e1 - the first set element
    e2 - the second set element
    e3 - the third set element
    e4 - the fourth set element
    e5 - the fifth set element
    e6 - the sixth set element
    Returns:
    the newly created set
    Throws:
    java.lang.IllegalArgumentException - if there are any duplicate elements
    java.lang.NullPointerException - if an element is null
    Since:
    9

method:of(E, E, E, E, E, E, E) [ADDED]

  • of

    static <E> Set<E> of(E e1,
                         E e2,
                         E e3,
                         E e4,
                         E e5,
                         E e6,
                         E e7)
    
    Creates an immutable set containing seven elements. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Parameters:
    e1 - the first set element
    e2 - the second set element
    e3 - the third set element
    e4 - the fourth set element
    e5 - the fifth set element
    e6 - the sixth set element
    e7 - the seventh set element
    Returns:
    the newly created set
    Throws:
    java.lang.IllegalArgumentException - if there are any duplicate elements
    java.lang.NullPointerException - if an element is null
    Since:
    9

method:of(E, E, E, E, E, E, E, E) [ADDED]

  • of

    static <E> Set<E> of(E e1,
                         E e2,
                         E e3,
                         E e4,
                         E e5,
                         E e6,
                         E e7,
                         E e8)
    
    Creates an immutable set containing eight elements. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Parameters:
    e1 - the first set element
    e2 - the second set element
    e3 - the third set element
    e4 - the fourth set element
    e5 - the fifth set element
    e6 - the sixth set element
    e7 - the seventh set element
    e8 - the eighth set element
    Returns:
    the newly created set
    Throws:
    java.lang.IllegalArgumentException - if there are any duplicate elements
    java.lang.NullPointerException - if an element is null
    Since:
    9

method:of(E, E, E, E, E, E, E, E, E) [ADDED]

  • of

    static <E> Set<E> of(E e1,
                         E e2,
                         E e3,
                         E e4,
                         E e5,
                         E e6,
                         E e7,
                         E e8,
                         E e9)
    
    Creates an immutable set containing nine elements. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Parameters:
    e1 - the first set element
    e2 - the second set element
    e3 - the third set element
    e4 - the fourth set element
    e5 - the fifth set element
    e6 - the sixth set element
    e7 - the seventh set element
    e8 - the eighth set element
    e9 - the ninth set element
    Returns:
    the newly created set
    Throws:
    java.lang.IllegalArgumentException - if there are any duplicate elements
    java.lang.NullPointerException - if an element is null
    Since:
    9

method:of(E, E, E, E, E, E, E, E, E, E) [ADDED]

  • of

    static <E> Set<E> of(E e1,
                         E e2,
                         E e3,
                         E e4,
                         E e5,
                         E e6,
                         E e7,
                         E e8,
                         E e9,
                         E e10)
    
    Creates an immutable set containing ten elements. See Immutable Set Static Factory Methods for details.
    Type Parameters:
    E - the set's element type
    Parameters:
    e1 - the first set element
    e2 - the second set element
    e3 - the third set element
    e4 - the fourth set element
    e5 - the fifth set element
    e6 - the sixth set element
    e7 - the seventh set element
    e8 - the eighth set element
    e9 - the ninth set element
    e10 - the tenth set element
    Returns:
    the newly created set
    Throws:
    java.lang.IllegalArgumentException - if there are any duplicate elements
    java.lang.NullPointerException - if an element is null
    Since:
    9

method:of(E...) [ADDED]

  • of

    @SafeVarargs
    static <E> Set<E> of(E... es)
    
    Creates an immutable set containing an arbitrary number of elements. See Immutable Set Static Factory Methods for details.
    API Note:
    This method also accepts a single array as an argument. The element type of the resulting set will be the component type of the array, and the size of the set will be equal to the length of the array. To create a set with a single element that is an array, do the following:
    
         String[] array = ... ;
         Set<String[]> list = Set.<String[]>of(array);
     
    
    This will cause the Set.of(E) method to be invoked instead.
    Type Parameters:
    E - the set's element type
    Parameters:
    es - the elements to be contained in the set
    Returns:
    the newly created set
    Throws:
    java.lang.IllegalArgumentException - if there are any duplicate elements
    java.lang.NullPointerException - if an element is null or if the array is null
    Since:
    9