Class ImmutableList<E>
- java.lang.Object
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- java.util.AbstractCollection<E>
-
- com.google.common.collect.ImmutableCollection<E>
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- com.google.common.collect.ImmutableList<E>
-
- All Implemented Interfaces:
Serializable
,Iterable<E>
,Collection<E>
,List<E>
,RandomAccess
@GwtCompatible(serializable=true, emulated=true) public abstract class ImmutableList<E> extends ImmutableCollection<E> implements List<E>, RandomAccess
AList
whose contents will never change, with many other important properties detailed atImmutableCollection
.See the Guava User Guide article on immutable collections.
- Since:
- 2.0
- Author:
- Kevin Bourrillion
- See Also:
ImmutableMap
,ImmutableSet
, Serialized Form
-
-
Nested Class Summary
Nested Classes Modifier and Type Class Description static class
ImmutableList.Builder<E>
A builder for creating immutable list instances, especiallypublic static final
lists ("constant lists").
-
Method Summary
All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods Modifier and Type Method Description void
add(int index, E element)
Deprecated.Unsupported operation.boolean
addAll(int index, Collection<? extends E> newElements)
Deprecated.Unsupported operation.ImmutableList<E>
asList()
Deprecated.There is no reason to use this; it always returnsthis
.static <E> ImmutableList.Builder<E>
builder()
Returns a new builder.static <E> ImmutableList.Builder<E>
builderWithExpectedSize(int expectedSize)
Returns a new builder, expecting the specified number of elements to be added.boolean
contains(Object object)
Returnstrue
if this collection contains the specified element.static <E> ImmutableList<E>
copyOf(E[] elements)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
copyOf(Iterable<? extends E> elements)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
copyOf(Collection<? extends E> elements)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
copyOf(Iterator<? extends E> elements)
Returns an immutable list containing the given elements, in order.boolean
equals(Object obj)
Indicates whether some other object is "equal to" this one.void
forEach(Consumer<? super E> consumer)
Performs the given action for each element of theIterable
until all elements have been processed or the action throws an exception.int
hashCode()
Returns a hash code value for the object.int
indexOf(Object object)
Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element.UnmodifiableIterator<E>
iterator()
Returns an unmodifiable iterator across the elements in this collection.int
lastIndexOf(Object object)
Returns the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element.UnmodifiableListIterator<E>
listIterator()
Returns a list iterator over the elements in this list (in proper sequence).UnmodifiableListIterator<E>
listIterator(int index)
Returns a list iterator over the elements in this list (in proper sequence), starting at the specified position in the list.static <E> ImmutableList<E>
of()
Returns the empty immutable list.static <E> ImmutableList<E>
of(E element)
Returns an immutable list containing a single element.static <E> ImmutableList<E>
of(E e1, E e2)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
of(E e1, E e2, E e3)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
of(E e1, E e2, E e3, E e4)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
of(E e1, E e2, E e3, E e4, E e5)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
of(E e1, E e2, E e3, E e4, E e5, E e6)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
of(E e1, E e2, E e3, E e4, E e5, E e6, E e7)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9, E e10)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9, E e10, E e11)
Returns an immutable list containing the given elements, in order.static <E> ImmutableList<E>
of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9, E e10, E e11, E e12, E... others)
Returns an immutable list containing the given elements, in order.E
remove(int index)
Deprecated.Unsupported operation.void
replaceAll(UnaryOperator<E> operator)
Deprecated.Unsupported operation.ImmutableList<E>
reverse()
Returns a view of this immutable list in reverse order.E
set(int index, E element)
Deprecated.Unsupported operation.void
sort(Comparator<? super E> c)
Deprecated.Unsupported operation.static <E extends Comparable<? super E>>
ImmutableList<E>sortedCopyOf(Iterable<? extends E> elements)
Returns an immutable list containing the given elements, sorted according to their natural order.static <E> ImmutableList<E>
sortedCopyOf(Comparator<? super E> comparator, Iterable<? extends E> elements)
Returns an immutable list containing the given elements, in sorted order relative to the specified comparator.Spliterator<E>
spliterator()
Creates aSpliterator
over the elements in this collection.ImmutableList<E>
subList(int fromIndex, int toIndex)
Returns an immutable list of the elements between the specifiedfromIndex
, inclusive, andtoIndex
, exclusive.static <E> Collector<E,?,ImmutableList<E>>
toImmutableList()
Returns aCollector
that accumulates the input elements into a newImmutableList
, in encounter order.-
Methods inherited from class com.google.common.collect.ImmutableCollection
add, addAll, clear, remove, removeAll, removeIf, retainAll, toArray, toArray
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Methods inherited from class java.util.AbstractCollection
containsAll, isEmpty, size, toString
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Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait
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Methods inherited from interface java.util.Collection
parallelStream, removeIf, stream, toArray
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-
-
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Method Detail
-
toImmutableList
public static <E> Collector<E,?,ImmutableList<E>> toImmutableList()
Returns aCollector
that accumulates the input elements into a newImmutableList
, in encounter order.- Since:
- 21.0
-
of
public static <E> ImmutableList<E> of()
Returns the empty immutable list. This list behaves and performs comparably toCollections.emptyList()
, and is preferable mainly for consistency and maintainability of your code.Performance note: the instance returned is a singleton.
- Type Parameters:
E
- theList
's element type- Returns:
- an empty
List
-
of
public static <E> ImmutableList<E> of(E element)
Returns an immutable list containing a single element. This list behaves and performs comparably toCollections.singletonList(T)
, but will not accept a null element. It is preferable mainly for consistency and maintainability of your code.- Type Parameters:
E
- theList
's element type- Parameters:
element
- the single element- Returns:
- a
List
containing the specified element - Throws:
NullPointerException
- ifelement
is null
-
of
public static <E> ImmutableList<E> of(E e1, E e2)
Returns an immutable list containing the given elements, in order.- Type Parameters:
E
- theList
's element type- Parameters:
e1
- the first elemente2
- the second element- Returns:
- a
List
containing the specified elements - Throws:
NullPointerException
- if any element is null
-
of
public static <E> ImmutableList<E> of(E e1, E e2, E e3)
Returns an immutable list containing the given elements, in order.- Type Parameters:
E
- theList
's element type- Parameters:
e1
- the first elemente2
- the second elemente3
- the third element- Returns:
- a
List
containing the specified elements - Throws:
NullPointerException
- if any element is null
-
of
public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4)
Returns an immutable list containing the given elements, in order.- Type Parameters:
E
- theList
's element type- Parameters:
e1
- the first elemente2
- the second elemente3
- the third elemente4
- the fourth element- Returns:
- a
List
containing the specified elements - Throws:
NullPointerException
- if any element is null
-
of
public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5)
Returns an immutable list containing the given elements, in order.- Type Parameters:
E
- theList
's element type- Parameters:
e1
- the first elemente2
- the second elemente3
- the third elemente4
- the fourth elemente5
- the fifth element- Returns:
- a
List
containing the specified elements - Throws:
NullPointerException
- if any element is null
-
of
public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5, E e6)
Returns an immutable list containing the given elements, in order.- Type Parameters:
E
- theList
's element type- Parameters:
e1
- the first elemente2
- the second elemente3
- the third elemente4
- the fourth elemente5
- the fifth elemente6
- the sixth element- Returns:
- a
List
containing the specified elements - Throws:
NullPointerException
- if any element is null
-
of
public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5, E e6, E e7)
Returns an immutable list containing the given elements, in order.- Type Parameters:
E
- theList
's element type- Parameters:
e1
- the first elemente2
- the second elemente3
- the third elemente4
- the fourth elemente5
- the fifth elemente6
- the sixth elemente7
- the seventh element- Returns:
- a
List
containing the specified elements - Throws:
NullPointerException
- if any element is null
-
of
public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8)
Returns an immutable list containing the given elements, in order.- Type Parameters:
E
- theList
's element type- Parameters:
e1
- the first elemente2
- the second elemente3
- the third elemente4
- the fourth elemente5
- the fifth elemente6
- the sixth elemente7
- the seventh elemente8
- the eighth element- Returns:
- a
List
containing the specified elements - Throws:
NullPointerException
- if any element is null
-
of
public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9)
Returns an immutable list containing the given elements, in order.- Type Parameters:
E
- theList
's element type- Parameters:
e1
- the first elemente2
- the second elemente3
- the third elemente4
- the fourth elemente5
- the fifth elemente6
- the sixth elemente7
- the seventh elemente8
- the eighth elemente9
- the ninth element- Returns:
- a
List
containing the specified elements - Throws:
NullPointerException
- if any element is null
-
of
public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9, E e10)
Returns an immutable list containing the given elements, in order.- Type Parameters:
E
- theList
's element type- Parameters:
e1
- the first elemente2
- the second elemente3
- the third elemente4
- the fourth elemente5
- the fifth elemente6
- the sixth elemente7
- the seventh elemente8
- the eighth elemente9
- the ninth elemente10
- the tenth element- Returns:
- a
List
containing the specified elements - Throws:
NullPointerException
- if any element is null
-
of
public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9, E e10, E e11)
Returns an immutable list containing the given elements, in order.- Throws:
NullPointerException
- if any element is null
-
of
@SafeVarargs public static <E> ImmutableList<E> of(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9, E e10, E e11, E e12, E... others)
Returns an immutable list containing the given elements, in order.The array
others
must not be longer thanInteger.MAX_VALUE - 12
.- Throws:
NullPointerException
- if any element is null- Since:
- 3.0 (source-compatible since 2.0)
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copyOf
public static <E> ImmutableList<E> copyOf(Iterable<? extends E> elements)
Returns an immutable list containing the given elements, in order. Ifelements
is aCollection
, this method behaves exactly ascopyOf(Collection)
; otherwise, it behaves exactly ascopyOf(elements.iterator()
.- Throws:
NullPointerException
- ifelements
contains a null element
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copyOf
public static <E> ImmutableList<E> copyOf(Collection<? extends E> elements)
Returns an immutable list containing the given elements, in order.Despite the method name, this method attempts to avoid actually copying the data when it is safe to do so. The exact circumstances under which a copy will or will not be performed are undocumented and subject to change.
Note that if
list
is aList<String>
, thenImmutableList.copyOf(list)
returns anImmutableList<String>
containing each of the strings inlist
, while ImmutableList.of(list)} returns anImmutableList<List<String>>
containing one element (the given list itself).This method is safe to use even when
elements
is a synchronized or concurrent collection that is currently being modified by another thread.- Type Parameters:
E
- theList
's element type- Parameters:
elements
- aCollection
from which elements are drawn, must be non-null- Returns:
- a
List
containing the elements of the givenCollection
- Throws:
NullPointerException
- ifelements
contains a null element
-
copyOf
public static <E> ImmutableList<E> copyOf(Iterator<? extends E> elements)
Returns an immutable list containing the given elements, in order.- Throws:
NullPointerException
- ifelements
contains a null element
-
copyOf
public static <E> ImmutableList<E> copyOf(E[] elements)
Returns an immutable list containing the given elements, in order.- Throws:
NullPointerException
- ifelements
contains a null element- Since:
- 3.0
-
sortedCopyOf
public static <E extends Comparable<? super E>> ImmutableList<E> sortedCopyOf(Iterable<? extends E> elements)
Returns an immutable list containing the given elements, sorted according to their natural order. The sorting algorithm used is stable, so elements that compare as equal will stay in the order in which they appear in the input.If your data has no duplicates, or you wish to deduplicate elements, use
ImmutableSortedSet.copyOf(elements)
; if you want aList
you can use itsasList()
view.Java 8 users: If you want to convert a
Stream
to a sortedImmutableList
, usestream.sorted().collect(toImmutableList())
.- Throws:
NullPointerException
- if any element in the input is null- Since:
- 21.0
-
sortedCopyOf
public static <E> ImmutableList<E> sortedCopyOf(Comparator<? super E> comparator, Iterable<? extends E> elements)
Returns an immutable list containing the given elements, in sorted order relative to the specified comparator. The sorting algorithm used is stable, so elements that compare as equal will stay in the order in which they appear in the input.If your data has no duplicates, or you wish to deduplicate elements, use
ImmutableSortedSet.copyOf(comparator, elements)
; if you want aList
you can use itsasList()
view.Java 8 users: If you want to convert a
Stream
to a sortedImmutableList
, usestream.sorted(comparator).collect(toImmutableList())
.- Throws:
NullPointerException
- if any element in the input is null- Since:
- 21.0
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iterator
public UnmodifiableIterator<E> iterator()
Description copied from class:ImmutableCollection
Returns an unmodifiable iterator across the elements in this collection.
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listIterator
public UnmodifiableListIterator<E> listIterator()
Description copied from interface:java.util.List
Returns a list iterator over the elements in this list (in proper sequence).- Specified by:
listIterator
in interfaceList<E>
- Returns:
- a list iterator over the elements in this list (in proper sequence)
-
listIterator
public UnmodifiableListIterator<E> listIterator(int index)
Description copied from interface:java.util.List
Returns a list iterator over the elements in this list (in proper sequence), starting at the specified position in the list. The specified index indicates the first element that would be returned by an initial call tonext
. An initial call toprevious
would return the element with the specified index minus one.- Specified by:
listIterator
in interfaceList<E>
- Parameters:
index
- index of the first element to be returned from the list iterator (by a call tonext
)- Returns:
- a list iterator over the elements in this list (in proper sequence), starting at the specified position in the list
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forEach
public void forEach(Consumer<? super E> consumer)
Description copied from interface:java.lang.Iterable
Performs the given action for each element of theIterable
until all elements have been processed or the action throws an exception. Actions are performed in the order of iteration, if that order is specified. Exceptions thrown by the action are relayed to the caller.The behavior of this method is unspecified if the action performs side-effects that modify the underlying source of elements, unless an overriding class has specified a concurrent modification policy.
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indexOf
public int indexOf(@CheckForNull Object object)
Description copied from interface:java.util.List
Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element. More formally, returns the lowest indexi
such thatObjects.equals(o, get(i))
, or -1 if there is no such index.
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lastIndexOf
public int lastIndexOf(@CheckForNull Object object)
Description copied from interface:java.util.List
Returns the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element. More formally, returns the highest indexi
such thatObjects.equals(o, get(i))
, or -1 if there is no such index.- Specified by:
lastIndexOf
in interfaceList<E>
- Parameters:
object
- element to search for- Returns:
- the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element
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contains
public boolean contains(@CheckForNull Object object)
Description copied from class:java.util.AbstractCollection
Returnstrue
if this collection contains the specified element. More formally, returnstrue
if and only if this collection contains at least one elemente
such thatObjects.equals(o, e)
.- Specified by:
contains
in interfaceCollection<E>
- Specified by:
contains
in interfaceList<E>
- Specified by:
contains
in classImmutableCollection<E>
- Parameters:
object
- element whose presence in this collection is to be tested- Returns:
true
if this collection contains the specified element
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subList
public ImmutableList<E> subList(int fromIndex, int toIndex)
Returns an immutable list of the elements between the specifiedfromIndex
, inclusive, andtoIndex
, exclusive. (IffromIndex
andtoIndex
are equal, the empty immutable list is returned.)
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addAll
@CanIgnoreReturnValue @Deprecated public final boolean addAll(int index, Collection<? extends E> newElements)
Deprecated.Unsupported operation.Guaranteed to throw an exception and leave the list unmodified.- Specified by:
addAll
in interfaceList<E>
- Parameters:
index
- index at which to insert the first element from the specified collectionnewElements
- collection containing elements to be added to this list- Returns:
true
if this list changed as a result of the call- Throws:
UnsupportedOperationException
- always
-
set
@CanIgnoreReturnValue @Deprecated public final E set(int index, E element)
Deprecated.Unsupported operation.Guaranteed to throw an exception and leave the list unmodified.- Specified by:
set
in interfaceList<E>
- Parameters:
index
- index of the element to replaceelement
- element to be stored at the specified position- Returns:
- the element previously at the specified position
- Throws:
UnsupportedOperationException
- always
-
add
@Deprecated public final void add(int index, E element)
Deprecated.Unsupported operation.Guaranteed to throw an exception and leave the list unmodified.- Specified by:
add
in interfaceList<E>
- Parameters:
index
- index at which the specified element is to be insertedelement
- element to be inserted- Throws:
UnsupportedOperationException
- always
-
remove
@CanIgnoreReturnValue @Deprecated public final E remove(int index)
Deprecated.Unsupported operation.Guaranteed to throw an exception and leave the list unmodified.- Specified by:
remove
in interfaceList<E>
- Parameters:
index
- the index of the element to be removed- Returns:
- the element previously at the specified position
- Throws:
UnsupportedOperationException
- always
-
replaceAll
@Deprecated public final void replaceAll(UnaryOperator<E> operator)
Deprecated.Unsupported operation.Guaranteed to throw an exception and leave the list unmodified.- Specified by:
replaceAll
in interfaceList<E>
- Parameters:
operator
- the operator to apply to each element- Throws:
UnsupportedOperationException
- always
-
sort
@Deprecated public final void sort(Comparator<? super E> c)
Deprecated.Unsupported operation.Guaranteed to throw an exception and leave the list unmodified.- Specified by:
sort
in interfaceList<E>
- Parameters:
c
- theComparator
used to compare list elements. Anull
value indicates that the elements' natural ordering should be used- Throws:
UnsupportedOperationException
- always
-
asList
@InlineMe(replacement="this") @Deprecated public final ImmutableList<E> asList()
Deprecated.There is no reason to use this; it always returnsthis
.Returns this list instance.- Overrides:
asList
in classImmutableCollection<E>
- Since:
- 2.0
-
spliterator
public Spliterator<E> spliterator()
Description copied from interface:java.util.Collection
Creates aSpliterator
over the elements in this collection. Implementations should document characteristic values reported by the spliterator. Such characteristic values are not required to be reported if the spliterator reportsSpliterator.SIZED
and this collection contains no elements.The default implementation should be overridden by subclasses that can return a more efficient spliterator. In order to preserve expected laziness behavior for the
Collection.stream()
andCollection.parallelStream()
methods, spliterators should either have the characteristic ofIMMUTABLE
orCONCURRENT
, or be late-binding. If none of these is practical, the overriding class should describe the spliterator's documented policy of binding and structural interference, and should override theCollection.stream()
andCollection.parallelStream()
methods to create streams using aSupplier
of the spliterator, as in:Stream<E> s = StreamSupport.stream(() -> spliterator(), spliteratorCharacteristics)
These requirements ensure that streams produced by the
Collection.stream()
andCollection.parallelStream()
methods will reflect the contents of the collection as of initiation of the terminal stream operation.- Specified by:
spliterator
in interfaceCollection<E>
- Specified by:
spliterator
in interfaceIterable<E>
- Specified by:
spliterator
in interfaceList<E>
- Overrides:
spliterator
in classImmutableCollection<E>
- Returns:
- a
Spliterator
over the elements in this collection
-
reverse
public ImmutableList<E> reverse()
Returns a view of this immutable list in reverse order. For example,ImmutableList.of(1, 2, 3).reverse()
is equivalent toImmutableList.of(3, 2, 1)
.- Returns:
- a view of this immutable list in reverse order
- Since:
- 7.0
-
equals
public boolean equals(@CheckForNull Object obj)
Description copied from class:java.lang.Object
Indicates whether some other object is "equal to" this one.The
equals
method implements an equivalence relation on non-null object references:- It is reflexive: for any non-null reference value
x
,x.equals(x)
should returntrue
. - It is symmetric: for any non-null reference values
x
andy
,x.equals(y)
should returntrue
if and only ify.equals(x)
returnstrue
. - It is transitive: for any non-null reference values
x
,y
, andz
, ifx.equals(y)
returnstrue
andy.equals(z)
returnstrue
, thenx.equals(z)
should returntrue
. - It is consistent: for any non-null reference values
x
andy
, multiple invocations ofx.equals(y)
consistently returntrue
or consistently returnfalse
, provided no information used inequals
comparisons on the objects is modified. - For any non-null reference value
x
,x.equals(null)
should returnfalse
.
The
equals
method for classObject
implements the most discriminating possible equivalence relation on objects; that is, for any non-null reference valuesx
andy
, this method returnstrue
if and only ifx
andy
refer to the same object (x == y
has the valuetrue
).Note that it is generally necessary to override the
hashCode
method whenever this method is overridden, so as to maintain the general contract for thehashCode
method, which states that equal objects must have equal hash codes.- Specified by:
equals
in interfaceCollection<E>
- Specified by:
equals
in interfaceList<E>
- Overrides:
equals
in classObject
- Parameters:
obj
- the reference object with which to compare.- Returns:
true
if this object is the same as the obj argument;false
otherwise.- See Also:
Object.hashCode()
,HashMap
- It is reflexive: for any non-null reference value
-
hashCode
public int hashCode()
Description copied from class:java.lang.Object
Returns a hash code value for the object. This method is supported for the benefit of hash tables such as those provided byHashMap
.The general contract of
hashCode
is:- Whenever it is invoked on the same object more than once during
an execution of a Java application, the
hashCode
method must consistently return the same integer, provided no information used inequals
comparisons on the object is modified. This integer need not remain consistent from one execution of an application to another execution of the same application. - If two objects are equal according to the
equals(Object)
method, then calling thehashCode
method on each of the two objects must produce the same integer result. - It is not required that if two objects are unequal
according to the
Object.equals(java.lang.Object)
method, then calling thehashCode
method on each of the two objects must produce distinct integer results. However, the programmer should be aware that producing distinct integer results for unequal objects may improve the performance of hash tables.
As much as is reasonably practical, the hashCode method defined by class
Object
does return distinct integers for distinct objects. (The hashCode may or may not be implemented as some function of an object's memory address at some point in time.)- Specified by:
hashCode
in interfaceCollection<E>
- Specified by:
hashCode
in interfaceList<E>
- Overrides:
hashCode
in classObject
- Returns:
- a hash code value for this object.
- See Also:
Object.equals(java.lang.Object)
,System.identityHashCode(java.lang.Object)
- Whenever it is invoked on the same object more than once during
an execution of a Java application, the
-
builder
public static <E> ImmutableList.Builder<E> builder()
Returns a new builder. The generated builder is equivalent to the builder created by theImmutableList.Builder
constructor.
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builderWithExpectedSize
@Beta public static <E> ImmutableList.Builder<E> builderWithExpectedSize(int expectedSize)
Returns a new builder, expecting the specified number of elements to be added.If
expectedSize
is exactly the number of elements added to the builder beforeImmutableList.Builder.build()
is called, the builder is likely to perform better than an unsizedbuilder()
would have.It is not specified if any performance benefits apply if
expectedSize
is close to, but not exactly, the number of elements added to the builder.- Since:
- 23.1
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