- Type Parameters:
- E- the enum type of elements maintained by this set
- All Implemented Interfaces:
- Serializable,- Cloneable,- Iterable<E>,- Collection<E>,- Set<E>
Set implementation for use with enum types.  All of
 the elements in an enum set must come from a single enum type that is
 specified, explicitly or implicitly, when the set is created.  Enum sets
 are represented internally as bit vectors.  This representation is
 extremely compact and efficient. The space and time performance of this
 class should be good enough to allow its use as a high-quality, typesafe
 alternative to traditional int-based "bit flags."  Even bulk
 operations (such as containsAll and retainAll) should
 run very quickly if their argument is also an enum set.
 The iterator returned by the iterator method traverses the
 elements in their natural order (the order in which the enum
 constants are declared).  The returned iterator is weakly
 consistent: it will never throw ConcurrentModificationException
 and it may or may not show the effects of any modifications to the set that
 occur while the iteration is in progress.
 
Null elements are not permitted.  Attempts to insert a null element
 will throw NullPointerException.  Attempts to test for the
 presence of a null element or to remove one will, however, function
 properly.
 
Like most collection implementations, EnumSet is not
 synchronized.  If multiple threads access an enum set concurrently, and at
 least one of the threads modifies the set, it should be synchronized
 externally.  This is typically accomplished by synchronizing on some
 object that naturally encapsulates the enum set.  If no such object exists,
 the set should be "wrapped" using the Collections.synchronizedSet(java.util.Set<T>)
 method.  This is best done at creation time, to prevent accidental
 unsynchronized access:
 
Set<MyEnum> s = Collections.synchronizedSet(EnumSet.noneOf(MyEnum.class));
Implementation note: All basic operations execute in constant time.
 They are likely (though not guaranteed) to be much faster than their
 HashSet counterparts.  Even bulk operations execute in
 constant time if their argument is also an enum set.
 
This class is a member of the Java Collections Framework.
- Since:
- 1.5
- See Also:
- 
Method SummaryModifier and TypeMethodDescriptionCreates an enum set containing all of the elements in the specified element type.clone()Returns a copy of this set.complementOf(EnumSet<E> s) Creates an enum set with the same element type as the specified enum set, initially containing all the elements of this type that are not contained in the specified set.copyOf(Collection<E> c) Creates an enum set initialized from the specified collection.Creates an enum set with the same element type as the specified enum set, initially containing the same elements (if any).Creates an empty enum set with the specified element type.of(E e) Creates an enum set initially containing the specified element.of(E e1, E e2) Creates an enum set initially containing the specified elements.of(E first, E... rest) Creates an enum set initially containing the specified elements.of(E e1, E e2, E e3) Creates an enum set initially containing the specified elements.of(E e1, E e2, E e3, E e4) Creates an enum set initially containing the specified elements.of(E e1, E e2, E e3, E e4, E e5) Creates an enum set initially containing the specified elements.range(E from, E to) Creates an enum set initially containing all of the elements in the range defined by the two specified endpoints.Methods declared in class java.util.AbstractSetequals, hashCode, removeAllMethods declared in class java.util.AbstractCollectionadd, addAll, clear, contains, containsAll, isEmpty, iterator, remove, retainAll, toArray, toArray, toStringMethods declared in interface java.util.CollectionparallelStream, removeIf, stream, toArray
- 
Method Details- 
noneOfCreates an empty enum set with the specified element type.- Type Parameters:
- E- The class of the elements in the set
- Parameters:
- elementType- the class object of the element type for this enum set
- Returns:
- An empty enum set of the specified type.
- Throws:
- NullPointerException- if- elementTypeis null
 
- 
allOfCreates an enum set containing all of the elements in the specified element type.- Type Parameters:
- E- The class of the elements in the set
- Parameters:
- elementType- the class object of the element type for this enum set
- Returns:
- An enum set containing all the elements in the specified type.
- Throws:
- NullPointerException- if- elementTypeis null
 
- 
copyOfCreates an enum set with the same element type as the specified enum set, initially containing the same elements (if any).- Type Parameters:
- E- The class of the elements in the set
- Parameters:
- s- the enum set from which to initialize this enum set
- Returns:
- A copy of the specified enum set.
- Throws:
- NullPointerException- if- sis null
 
- 
copyOfCreates an enum set initialized from the specified collection. If the specified collection is anEnumSetinstance, this static factory method behaves identically tocopyOf(EnumSet). Otherwise, the specified collection must contain at least one element (in order to determine the new enum set's element type).- Type Parameters:
- E- The class of the elements in the collection
- Parameters:
- c- the collection from which to initialize this enum set
- Returns:
- An enum set initialized from the given collection.
- Throws:
- IllegalArgumentException- if- cis not an- EnumSetinstance and contains no elements
- NullPointerException- if- cis null
 
- 
complementOfCreates an enum set with the same element type as the specified enum set, initially containing all the elements of this type that are not contained in the specified set.- Type Parameters:
- E- The class of the elements in the enum set
- Parameters:
- s- the enum set from whose complement to initialize this enum set
- Returns:
- The complement of the specified set in this set
- Throws:
- NullPointerException- if- sis null
 
- 
ofCreates an enum set initially containing the specified element. Overloadings of this method exist to initialize an enum set with one through five elements. A sixth overloading is provided that uses the varargs feature. This overloading may be used to create an enum set initially containing an arbitrary number of elements, but is likely to run slower than the overloadings that do not use varargs.- Type Parameters:
- E- The class of the specified element and of the set
- Parameters:
- e- the element that this set is to contain initially
- Returns:
- an enum set initially containing the specified element
- Throws:
- NullPointerException- if- eis null
 
- 
ofCreates an enum set initially containing the specified elements. Overloadings of this method exist to initialize an enum set with one through five elements. A sixth overloading is provided that uses the varargs feature. This overloading may be used to create an enum set initially containing an arbitrary number of elements, but is likely to run slower than the overloadings that do not use varargs.- Type Parameters:
- E- The class of the parameter elements and of the set
- Parameters:
- e1- an element that this set is to contain initially
- e2- another element that this set is to contain initially
- Returns:
- an enum set initially containing the specified elements
- Throws:
- NullPointerException- if any parameters are null
 
- 
ofCreates an enum set initially containing the specified elements. Overloadings of this method exist to initialize an enum set with one through five elements. A sixth overloading is provided that uses the varargs feature. This overloading may be used to create an enum set initially containing an arbitrary number of elements, but is likely to run slower than the overloadings that do not use varargs.- Type Parameters:
- E- The class of the parameter elements and of the set
- Parameters:
- e1- an element that this set is to contain initially
- e2- another element that this set is to contain initially
- e3- another element that this set is to contain initially
- Returns:
- an enum set initially containing the specified elements
- Throws:
- NullPointerException- if any parameters are null
 
- 
ofCreates an enum set initially containing the specified elements. Overloadings of this method exist to initialize an enum set with one through five elements. A sixth overloading is provided that uses the varargs feature. This overloading may be used to create an enum set initially containing an arbitrary number of elements, but is likely to run slower than the overloadings that do not use varargs.- Type Parameters:
- E- The class of the parameter elements and of the set
- Parameters:
- e1- an element that this set is to contain initially
- e2- another element that this set is to contain initially
- e3- another element that this set is to contain initially
- e4- another element that this set is to contain initially
- Returns:
- an enum set initially containing the specified elements
- Throws:
- NullPointerException- if any parameters are null
 
- 
ofCreates an enum set initially containing the specified elements. Overloadings of this method exist to initialize an enum set with one through five elements. A sixth overloading is provided that uses the varargs feature. This overloading may be used to create an enum set initially containing an arbitrary number of elements, but is likely to run slower than the overloadings that do not use varargs.- Type Parameters:
- E- The class of the parameter elements and of the set
- Parameters:
- e1- an element that this set is to contain initially
- e2- another element that this set is to contain initially
- e3- another element that this set is to contain initially
- e4- another element that this set is to contain initially
- e5- another element that this set is to contain initially
- Returns:
- an enum set initially containing the specified elements
- Throws:
- NullPointerException- if any parameters are null
 
- 
ofCreates an enum set initially containing the specified elements. This factory, whose parameter list uses the varargs feature, may be used to create an enum set initially containing an arbitrary number of elements, but it is likely to run slower than the overloadings that do not use varargs.- Type Parameters:
- E- The class of the parameter elements and of the set
- Parameters:
- first- an element that the set is to contain initially
- rest- the remaining elements the set is to contain initially
- Returns:
- an enum set initially containing the specified elements
- Throws:
- NullPointerException- if any of the specified elements are null, or if- restis null
 
- 
rangeCreates an enum set initially containing all of the elements in the range defined by the two specified endpoints. The returned set will contain the endpoints themselves, which may be identical but must not be out of order.- Type Parameters:
- E- The class of the parameter elements and of the set
- Parameters:
- from- the first element in the range
- to- the last element in the range
- Returns:
- an enum set initially containing all of the elements in the range defined by the two specified endpoints
- Throws:
- NullPointerException- if- fromor- toare null
- IllegalArgumentException- if- from.compareTo(to) > 0
 
- 
cloneReturns a copy of this set.
 
-