Sets (net.sourceforge.streamsupport:streamsupport 1.7.0 API)

java.lang.Object
- java8.util.Sets

```
public final class Sets
extends Object
```
A place for the new Java 9 JEP 269 "Unmodifiable Set Static Factory Methods" in the Set interface.
Unmodifiable Sets

The Sets.of and Sets.copyOf static factory methods provide a convenient way to create unmodifiable sets. The Set instances created by these methods have the following characteristics:
- They are unmodifiable. Elements cannot be added or removed. Calling any mutator method on the Set will always cause UnsupportedOperationException to be thrown. However, if the contained elements are themselves mutable, this may cause the Set to behave inconsistently or its contents to appear to change.
- 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.
- The iteration order of set elements is unspecified and is subject to change.
- They are value-based. Callers should make no assumptions about the identity of the returned instances. Factories are free to create new instances or reuse existing ones. Therefore, identity-sensitive operations on these instances (reference equality ( ==), identity hash code, and synchronization) are unreliable and should be avoided.
Since:

9

Method Summary

All Methods Static Methods Concrete Methods
Modifier and Type	Method and Description
`static <E> Set<E>`	`copyOf(Collection<? extends E> coll)` Returns an unmodifiable Set containing the elements of the given Collection.
`static <E> Set<E>`	`of()` Returns an unmodifiable set containing zero elements.
`static <E> Set<E>`	`of(E... elements)` Returns an unmodifiable set containing an arbitrary number of elements.
`static <E> Set<E>`	`of(E e1)` Returns an unmodifiable set containing one element.
`static <E> Set<E>`	`of(E e1, E e2)` Returns an unmodifiable set containing two elements.
`static <E> Set<E>`	`of(E e1, E e2, E e3)` Returns an unmodifiable set containing three elements.
`static <E> Set<E>`	`of(E e1, E e2, E e3, E e4)` Returns an unmodifiable set containing four elements.
`static <E> Set<E>`	`of(E e1, E e2, E e3, E e4, E e5)` Returns an unmodifiable set containing five elements.
`static <E> Set<E>`	`of(E e1, E e2, E e3, E e4, E e5, E e6)` Returns an unmodifiable set containing six elements.
`static <E> Set<E>`	`of(E e1, E e2, E e3, E e4, E e5, E e6, E e7)` Returns an unmodifiable set containing seven elements.
`static <E> Set<E>`	`of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8)` Returns an unmodifiable set containing eight elements.
`static <E> Set<E>`	`of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9)` Returns an unmodifiable set containing nine elements.
`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)` Returns an unmodifiable set containing ten elements.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Method Detail
  - of
```
public static <E> Set<E> of()
```
    Returns an unmodifiable set containing zero elements. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Returns:
    
    an empty Set
    
    Since:
    
    9
  - of
```
public static <E> Set<E> of(E e1)
```
    Returns an unmodifiable set containing one element. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    e1 - the single element
    
    Returns:
    
    a Set containing the specified element
    
    Throws:
    
    NullPointerException - if the element is null
    
    Since:
    
    9
  - of
```
public static <E> Set<E> of(E e1,
                            E e2)
```
    Returns an unmodifiable set containing two elements. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    e1 - the first element
    
    e2 - the second element
    
    Returns:
    
    a Set containing the specified elements
    
    Throws:
    
    IllegalArgumentException - if the elements are duplicates
    
    NullPointerException - if an element is null
    
    Since:
    
    9
  - of
```
public static <E> Set<E> of(E e1,
                            E e2,
                            E e3)
```
    Returns an unmodifiable set containing three elements. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    e1 - the first element
    
    e2 - the second element
    
    e3 - the third element
    
    Returns:
    
    a Set containing the specified elements
    
    Throws:
    
    IllegalArgumentException - if there are any duplicate elements
    
    NullPointerException - if an element is null
    
    Since:
    
    9
  - of
```
public static <E> Set<E> of(E e1,
                            E e2,
                            E e3,
                            E e4)
```
    Returns an unmodifiable set containing four elements. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    e1 - the first element
    
    e2 - the second element
    
    e3 - the third element
    
    e4 - the fourth element
    
    Returns:
    
    a Set containing the specified elements
    
    Throws:
    
    IllegalArgumentException - if there are any duplicate elements
    
    NullPointerException - if an element is null
    
    Since:
    
    9
  - of
```
public static <E> Set<E> of(E e1,
                            E e2,
                            E e3,
                            E e4,
                            E e5)
```
    Returns an unmodifiable set containing five elements. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    e1 - the first element
    
    e2 - the second element
    
    e3 - the third element
    
    e4 - the fourth element
    
    e5 - the fifth element
    
    Returns:
    
    a Set containing the specified elements
    
    Throws:
    
    IllegalArgumentException - if there are any duplicate elements
    
    NullPointerException - if an element is null
    
    Since:
    
    9
  - of
```
public static <E> Set<E> of(E e1,
                            E e2,
                            E e3,
                            E e4,
                            E e5,
                            E e6)
```
    Returns an unmodifiable set containing six elements. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    e1 - the first element
    
    e2 - the second element
    
    e3 - the third element
    
    e4 - the fourth element
    
    e5 - the fifth element
    
    e6 - the sixth element
    
    Returns:
    
    a Set containing the specified elements
    
    Throws:
    
    IllegalArgumentException - if there are any duplicate elements
    
    NullPointerException - if an element is null
    
    Since:
    
    9
  - of
```
public static <E> Set<E> of(E e1,
                            E e2,
                            E e3,
                            E e4,
                            E e5,
                            E e6,
                            E e7)
```
    Returns an unmodifiable set containing seven elements. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    e1 - the first element
    
    e2 - the second element
    
    e3 - the third element
    
    e4 - the fourth element
    
    e5 - the fifth element
    
    e6 - the sixth element
    
    e7 - the seventh element
    
    Returns:
    
    a Set containing the specified elements
    
    Throws:
    
    IllegalArgumentException - if there are any duplicate elements
    
    NullPointerException - if an element is null
    
    Since:
    
    9
  - of
```
public static <E> Set<E> of(E e1,
                            E e2,
                            E e3,
                            E e4,
                            E e5,
                            E e6,
                            E e7,
                            E e8)
```
    Returns an unmodifiable set containing eight elements. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    e1 - the first element
    
    e2 - the second element
    
    e3 - the third element
    
    e4 - the fourth element
    
    e5 - the fifth element
    
    e6 - the sixth element
    
    e7 - the seventh element
    
    e8 - the eighth element
    
    Returns:
    
    a Set containing the specified elements
    
    Throws:
    
    IllegalArgumentException - if there are any duplicate elements
    
    NullPointerException - if an element is null
    
    Since:
    
    9
  - of
```
public static <E> Set<E> of(E e1,
                            E e2,
                            E e3,
                            E e4,
                            E e5,
                            E e6,
                            E e7,
                            E e8,
                            E e9)
```
    Returns an unmodifiable set containing nine elements. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    e1 - the first element
    
    e2 - the second element
    
    e3 - the third element
    
    e4 - the fourth element
    
    e5 - the fifth element
    
    e6 - the sixth element
    
    e7 - the seventh element
    
    e8 - the eighth element
    
    e9 - the ninth element
    
    Returns:
    
    a Set containing the specified elements
    
    Throws:
    
    IllegalArgumentException - if there are any duplicate elements
    
    NullPointerException - if an element is null
    
    Since:
    
    9
  - of
```
public 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)
```
    Returns an unmodifiable set containing ten elements. See Unmodifiable Sets for details.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    e1 - the first element
    
    e2 - the second element
    
    e3 - the third element
    
    e4 - the fourth element
    
    e5 - the fifth element
    
    e6 - the sixth element
    
    e7 - the seventh element
    
    e8 - the eighth element
    
    e9 - the ninth element
    
    e10 - the tenth element
    
    Returns:
    
    a Set containing the specified elements
    
    Throws:
    
    IllegalArgumentException - if there are any duplicate elements
    
    NullPointerException - if an element is null
    
    Since:
    
    9
  - of
```
public static <E> Set<E> of(E... elements)
```
    Returns an unmodifiable set containing an arbitrary number of elements. See Unmodifiable Sets 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 = Sets.<String[]>of(array);
 
```
    This will cause the Sets.of(E) method to be invoked instead.
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    elements - the elements to be contained in the set
    
    Returns:
    
    a Set containing the specified elements
    
    Throws:
    
    IllegalArgumentException - if there are any duplicate elements
    
    NullPointerException - if an element is null or if the array is null
    
    Since:
    
    9
  - copyOf
```
public static <E> Set<E> copyOf(Collection<? extends E> coll)
```
    Returns an unmodifiable Set containing the elements of the given Collection. The given Collection must not be null, and it must not contain any null elements. If the given Collection contains duplicate elements, an arbitrary element of the duplicates is preserved. If the given Collection is subsequently modified, the returned Set will not reflect such modifications.
    Implementation Note: If the given Collection is an unmodifiable Set, calling copyOf will generally not create a copy.
    
    Type Parameters:
    
    E - the Set's element type
    
    Parameters:
    
    coll - the collection from which elements are drawn, must be non-null
    
    Returns:
    
    a Set containing the elements of the given Collection
    
    Throws:
    
    NullPointerException - if coll is null, or if it contains any nulls
    
    Since:
    
    10

Class Sets

Unmodifiable Sets

Method Summary

Methods inherited from class java.lang.Object

Method Detail

of

of

of

of

of

of

of

of

of

of

of

of

copyOf