public class IntArrayList extends AbstractIntList implements java.util.RandomAccess, java.lang.Cloneable, java.io.Serializable
This class implements a lightweight, fast, open, optimized,
reuse-oriented version of array-based lists. Instances of this class
represent a list with an array that is enlarged as needed when new entries
are created (by increasing its current length by 50%), but is
never made smaller (even on a clear()
). A family of
trimming methods lets you control the size of the
backing array; this is particularly useful if you reuse instances of this class.
Range checks are equivalent to those of java.util
's classes, but
they are delayed as much as possible. The backing array is exposed by the
elements()
method.
This class implements the bulk methods removeElements()
,
addElements()
and getElements()
using
high-performance system calls (e.g., System.arraycopy()
) instead of
expensive loops.
ArrayList
,
Serialized FormAbstractIntList.IntRandomAccessSubList, AbstractIntList.IntSubList
Modifier and Type | Field and Description |
---|---|
static int |
DEFAULT_INITIAL_CAPACITY
The initial default capacity of an array list.
|
Constructor and Description |
---|
IntArrayList()
Creates a new array list with
DEFAULT_INITIAL_CAPACITY capacity. |
IntArrayList(java.util.Collection<? extends java.lang.Integer> c)
Creates a new array list and fills it with a given collection.
|
IntArrayList(int capacity)
Creates a new array list with given capacity.
|
IntArrayList(int[] a)
Creates a new array list and fills it with the elements of a given array.
|
IntArrayList(int[] a,
int offset,
int length)
Creates a new array list and fills it with the elements of a given array.
|
IntArrayList(IntCollection c)
Creates a new array list and fills it with a given type-specific collection.
|
IntArrayList(IntIterator i)
Creates a new array list and fills it with the elements returned by a type-specific iterator..
|
IntArrayList(IntList l)
Creates a new array list and fills it with a given type-specific list.
|
IntArrayList(java.util.Iterator<? extends java.lang.Integer> i)
Creates a new array list and fills it with the elements returned by an iterator..
|
Modifier and Type | Method and Description |
---|---|
boolean |
add(int k)
Ensures that this collection contains the specified element (optional operation).
|
void |
add(int index,
int k)
Inserts the specified element at the specified position in this list (optional operation).
|
boolean |
addAll(int index,
IntCollection c)
Inserts all of the elements in the specified type-specific collection into this type-specific list at the specified position (optional operation).
|
boolean |
addAll(int index,
IntList l)
Inserts all of the elements in the specified type-specific list into this type-specific list at the specified position (optional operation).
|
void |
addElements(int index,
int[] a,
int offset,
int length)
Adds elements to this type-specific list using optimized system calls.
|
void |
clear() |
IntArrayList |
clone() |
int |
compareTo(IntArrayList l)
Compares this array list to another array list.
|
int |
compareTo(java.util.List<? extends java.lang.Integer> l)
Compares this list to another object.
|
int[] |
elements()
Returns the backing array of this list.
|
void |
ensureCapacity(int capacity)
Ensures that this array list can contain the given number of entries without resizing.
|
boolean |
equals(IntArrayList l)
Compares this type-specific array list to another one.
|
boolean |
equals(java.lang.Object o) |
void |
forEach(java.util.function.IntConsumer action)
Performs the given action for each element of this type-specific
Iterable
until all elements have been processed or the action throws an
exception. |
void |
getElements(int from,
int[] a,
int offset,
int length)
Copies element of this type-specific list into the given array using optimized system calls.
|
int |
getInt(int index)
Returns the element at the specified position in this list.
|
int |
indexOf(int k)
Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element.
|
boolean |
isEmpty()
Checks whether the stack is empty.
|
int |
lastIndexOf(int k)
Returns the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element.
|
IntListIterator |
listIterator(int index)
Returns a type-specific list iterator on the list starting at a given index.
|
static IntArrayList |
of()
Creates a new empty array list.
|
static IntArrayList |
of(int... init)
Creates an array list using an array of elements.
|
boolean |
rem(int k)
Removes a single instance of the specified element from this collection, if it is present (optional operation).
|
boolean |
removeAll(IntCollection c)
Remove from this collection all elements in the given type-specific collection.
|
void |
removeElements(int from,
int to)
Removes elements of this type-specific list using optimized system calls.
|
int |
removeInt(int index)
Removes the element at the specified position in this list (optional operation).
|
int |
set(int index,
int k)
Replaces the element at the specified position in this list with the specified element (optional operation).
|
void |
setElements(int index,
int[] a,
int offset,
int length)
Sets elements to this type-specific list using optimized system calls.
|
int |
size() |
void |
size(int size)
Sets the size of this list.
|
void |
sort(IntComparator comp)
Sort a list using a type-specific comparator.
|
IntSpliterator |
spliterator()
Returns a type-specific spliterator on the elements of this list.
|
IntList |
subList(int from,
int to)
Returns a type-specific view of the portion of this list from the index
from , inclusive, to the index to , exclusive. |
int[] |
toArray(int[] a)
Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array.
|
static IntArrayList |
toList(java.util.stream.IntStream stream)
Collects the result of a primitive
Stream into a new ArrayList. |
static IntArrayList |
toListWithExpectedSize(java.util.stream.IntStream stream,
int expectedSize)
Collects the result of a primitive
Stream into a new ArrayList, potentially pre-allocated to handle the given size. |
void |
trim()
Trims this array list so that the capacity is equal to the size.
|
void |
trim(int n)
Trims the backing array if it is too large.
|
void |
unstableSort(IntComparator comp)
Sorts this list using a sort not assured to be stable.
|
static IntArrayList |
wrap(int[] a)
Wraps a given array into an array list.
|
static IntArrayList |
wrap(int[] a,
int length)
Wraps a given array into an array list of given size.
|
addAll, addAll, addAll, addElements, contains, hashCode, iterator, listIterator, peekInt, popInt, push, replaceAll, toIntArray, topInt, toString
add, contains, containsAll, containsAll, forEach, remove, removeAll, removeIf, retainAll, retainAll, toIntArray
add, add, addAll, contains, get, indexOf, lastIndexOf, of, of, of, remove, remove, replaceAll, replaceAll, set, setElements, setElements, sort, unstableSort
containsAll, intIterator, intParallelStream, intSpliterator, intStream, parallelStream, removeIf, removeIf, removeIf, retainAll, stream, toIntArray
forEach, forEach
public static final int DEFAULT_INITIAL_CAPACITY
public IntArrayList(int capacity)
capacity
- the initial capacity of the array list (may be 0).public IntArrayList()
DEFAULT_INITIAL_CAPACITY
capacity.public IntArrayList(java.util.Collection<? extends java.lang.Integer> c)
c
- a collection that will be used to fill the array list.public IntArrayList(IntCollection c)
c
- a type-specific collection that will be used to fill the array list.public IntArrayList(IntList l)
l
- a type-specific list that will be used to fill the array list.public IntArrayList(int[] a)
a
- an array whose elements will be used to fill the array list.public IntArrayList(int[] a, int offset, int length)
a
- an array whose elements will be used to fill the array list.offset
- the first element to use.length
- the number of elements to use.public IntArrayList(java.util.Iterator<? extends java.lang.Integer> i)
i
- an iterator whose returned elements will fill the array list.public IntArrayList(IntIterator i)
i
- a type-specific iterator whose returned elements will fill the array list.public int[] elements()
public static IntArrayList wrap(int[] a, int length)
Note it is guaranteed
that the type of the array returned by elements()
will be the same
(see the comments in the class documentation).
a
- an array to wrap.length
- the length of the resulting array list.public static IntArrayList wrap(int[] a)
Note it is guaranteed
that the type of the array returned by elements()
will be the same
(see the comments in the class documentation).
a
- an array to wrap.public static IntArrayList of()
public static IntArrayList of(int... init)
of
in interface IntList
init
- a the array the will become the new backing array of the array list.wrap(int[], int)
public static IntArrayList toList(java.util.stream.IntStream stream)
Stream
into a new ArrayList.
This method performs a terminal operation on the given Stream
Collector
is necessary because there is no
primitive Collector
equivalent in the Java API.public static IntArrayList toListWithExpectedSize(java.util.stream.IntStream stream, int expectedSize)
Stream
into a new ArrayList, potentially pre-allocated to handle the given size.
This method performs a terminal operation on the given Stream
Collector
is necessary because there is no
primitive Collector
equivalent in the Java API.public void ensureCapacity(int capacity)
capacity
- the new minimum capacity for this array list.public void add(int index, int k)
AbstractIntList
add
in interface IntList
add
in class AbstractIntList
List.add(int,Object)
public boolean add(int k)
AbstractIntList
add
in interface IntCollection
add
in interface IntList
add
in class AbstractIntList
Collection.add(Object)
public int getInt(int index)
IntList
public int indexOf(int k)
IntList
indexOf
in interface IntList
indexOf
in class AbstractIntList
List.indexOf(Object)
public int lastIndexOf(int k)
IntList
lastIndexOf
in interface IntList
lastIndexOf
in class AbstractIntList
List.lastIndexOf(Object)
public int removeInt(int index)
AbstractIntList
removeInt
in interface IntList
removeInt
in class AbstractIntList
List.remove(int)
public boolean rem(int k)
AbstractIntList
rem
in interface IntCollection
rem
in class AbstractIntList
List.remove(Object)
public int set(int index, int k)
AbstractIntList
set
in interface IntList
set
in class AbstractIntList
List.set(int,Object)
public void clear()
AbstractIntList
clear
in interface java.util.Collection<java.lang.Integer>
clear
in interface java.util.List<java.lang.Integer>
clear
in class AbstractIntList
public int size()
size
in interface java.util.Collection<java.lang.Integer>
size
in interface java.util.List<java.lang.Integer>
size
in class java.util.AbstractCollection<java.lang.Integer>
public void size(int size)
IntList
If the specified size is smaller than the current size, the last elements are
discarded. Otherwise, they are filled with 0/null
/false
.
size
in interface IntList
size
in class AbstractIntList
size
- the new size.public boolean isEmpty()
Stack
isEmpty
in interface Stack<java.lang.Integer>
isEmpty
in interface java.util.Collection<java.lang.Integer>
isEmpty
in interface java.util.List<java.lang.Integer>
isEmpty
in class java.util.AbstractCollection<java.lang.Integer>
public void trim()
ArrayList.trimToSize()
public void trim(int n)
n
, this method does nothing. Otherwise, it trims the
array length to the maximum between n
and size()
.
This method is useful when reusing lists. Clearing a list leaves the array length untouched. If you are reusing a list many times, you can call this method with a typical size to avoid keeping around a very large array just because of a few large transient lists.
n
- the threshold for the trimming.public IntList subList(int from, int to)
IntList
from
, inclusive, to the index to
, exclusive.subList
in interface IntList
subList
in interface java.util.List<java.lang.Integer>
subList
in class AbstractIntList
List.subList(int,int)
public void getElements(int from, int[] a, int offset, int length)
getElements
in interface IntList
getElements
in class AbstractIntList
from
- the start index (inclusive).a
- the destination array.offset
- the offset into the destination array where to store the first element copied.length
- the number of elements to be copied.public void removeElements(int from, int to)
removeElements
in interface IntList
removeElements
in class AbstractIntList
from
- the start index (inclusive).to
- the end index (exclusive).public void addElements(int index, int[] a, int offset, int length)
addElements
in interface IntList
addElements
in class AbstractIntList
index
- the index at which to add elements.a
- the array containing the elements.offset
- the offset of the first element to add.length
- the number of elements to add.public void setElements(int index, int[] a, int offset, int length)
setElements
in interface IntList
setElements
in class AbstractIntList
index
- the index at which to start setting elements.a
- the array containing the elements.offset
- the offset of the first element to add.length
- the number of elements to add.public void forEach(java.util.function.IntConsumer action)
AbstractIntList
Iterable
until all elements have been processed or the action throws an
exception.forEach
in interface IntIterable
forEach
in class AbstractIntList
action
- the action to be performed for each element.Iterable.forEach(java.util.function.Consumer)
public boolean addAll(int index, IntCollection c)
IntList
addAll
in interface IntList
addAll
in class AbstractIntList
List.addAll(int,java.util.Collection)
public boolean addAll(int index, IntList l)
IntList
public boolean removeAll(IntCollection c)
IntCollection
removeAll
in interface IntCollection
removeAll
in class AbstractIntCollection
c
- a type-specific collection.true
if this collection changed as a result of the call.Collection.removeAll(Collection)
public int[] toArray(int[] a)
IntCollection
Note that, contrarily to Collection.toArray(Object[])
, this
methods just writes all elements of this collection: no special
value will be added after the last one.
toArray
in interface IntCollection
toArray
in class AbstractIntList
a
- if this array is big enough, it will be used to store this collection.Collection.toArray(Object[])
public IntListIterator listIterator(int index)
AbstractIntList
listIterator
in interface IntList
listIterator
in interface java.util.List<java.lang.Integer>
listIterator
in class AbstractIntList
List.listIterator(int)
public IntSpliterator spliterator()
List spliterators must report at least Spliterator.SIZED
and Spliterator.ORDERED
.
See List.spliterator()
for more documentation on the requirements
of the returned spliterator.
The returned spliterator is late-binding; it will track structural changes
after the current index, up until the first trySplit()
,
at which point the maximum index will be fixed.
Structural changes before the current index or after the first
trySplit()
will result in unspecified behavior.
spliterator
in interface IntCollection
spliterator
in interface IntIterable
spliterator
in interface IntList
spliterator
in interface java.lang.Iterable<java.lang.Integer>
spliterator
in interface java.util.Collection<java.lang.Integer>
spliterator
in interface java.util.List<java.lang.Integer>
public void sort(IntComparator comp)
IntList
Pass null
to sort using natural ordering.
public void unstableSort(IntComparator comp)
IntList
Pass null
to sort using natural ordering.
This differs from List.sort(java.util.Comparator)
in that the results are
not assured to be stable, but may be a bit faster.
Unless a subclass specifies otherwise, the results of the method if the list is concurrently modified during the sort are unspecified.
unstableSort
in interface IntList
public IntArrayList clone()
clone
in class java.lang.Object
public boolean equals(IntArrayList l)
l
- a type-specific array list.public boolean equals(java.lang.Object o)
equals
in interface java.util.Collection<java.lang.Integer>
equals
in interface java.util.List<java.lang.Integer>
equals
in class AbstractIntList
public int compareTo(IntArrayList l)
l
- an array list.public int compareTo(java.util.List<? extends java.lang.Integer> l)
AbstractIntList
List
, this method performs a lexicographical comparison; otherwise,
it throws a ClassCastException
.compareTo
in interface java.lang.Comparable<java.util.List<? extends java.lang.Integer>>
compareTo
in class AbstractIntList
l
- a list.List
, a negative integer,
zero, or a positive integer as this list is lexicographically less than, equal
to, or greater than the argument.