public class IntArrayList extends AbstractIntList implements RandomAccess, Cloneable, 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 doubling
its current length), 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.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(Collection<? extends 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(Iterator<? extends 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()
Removes all of the elements from this collection (optional operation).
|
IntArrayList |
clone()
Creates and returns a copy of this object.
|
int |
compareTo(IntArrayList l)
Compares this array list to another array list.
|
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.
|
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()
Returns true if this collection contains no elements.
|
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.
|
boolean |
rem(int k)
Removes a single instance of the specified element from this collection,
if it is present (optional operation).
|
boolean |
removeAll(Collection<?> c)
Removes all of this collection's elements that are also contained in the
specified collection (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).
|
int |
size()
Returns the number of elements in this collection.
|
void |
size(int size)
Sets the size of this list.
|
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.
|
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.
|
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.
|
add, addAll, addAll, addAll, addAll, addElements, compareTo, contains, equals, get, hashCode, indexOf, iterator, lastIndexOf, listIterator, peek, peekInt, pop, popInt, push, push, remove, set, subList, top, topInt, toStringadd, contains, containsAll, remove, retainAll, toIntArray, toIntArraycontainsAll, retainAll, toArray, toArraycontains, containsAll, remove, replaceAll, retainAll, sort, spliterator, toArray, toArraycontains, containsAll, remove, retainAll, toIntArray, toIntArrayparallelStream, removeIf, streamforEach, forEachpublic 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(Collection<? extends 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(Iterator<? extends 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 void ensureCapacity(int capacity)
capacity - the new minimum capacity for this array list.public void add(int index,
int k)
AbstractIntList
This implementation always throws an
UnsupportedOperationException.
add in interface IntListadd in class AbstractIntListList.add(int,Object)public boolean add(int k)
AbstractIntList
This implementation always throws an
UnsupportedOperationException.
This implementation delegates to the type-specific version of
List.add(int, Object).
add in interface IntCollectionadd in interface IntListadd in class AbstractIntListCollection.add(Object)public int getInt(int index)
IntListgetInt in interface IntListList.get(int)public int indexOf(int k)
IntListindexOf in interface IntListindexOf in class AbstractIntListList.indexOf(Object)public int lastIndexOf(int k)
IntListlastIndexOf in interface IntListlastIndexOf in class AbstractIntListList.lastIndexOf(Object)public int removeInt(int index)
AbstractIntList
This implementation always throws an
UnsupportedOperationException.
removeInt in interface IntListremoveInt in class AbstractIntListList.remove(int)public boolean rem(int k)
AbstractIntList
This implementation delegates to indexOf().
rem in interface IntCollectionrem in class AbstractIntListList.remove(Object)public int set(int index,
int k)
AbstractIntList
This implementation always throws an
UnsupportedOperationException.
set in interface IntListset in class AbstractIntListList.set(int,Object)public void clear()
AbstractIntListThis implementation iterates over this collection, removing each element using the Iterator.remove operation. Most implementations will probably choose to override this method for efficiency.
Note that this implementation will throw an UnsupportedOperationException if the iterator returned by this collection's iterator method does not implement the remove method and this collection is non-empty.
This implementation delegates to AbstractIntList.removeElements(int, int).
clear in interface Collection<Integer>clear in interface List<Integer>clear in class AbstractIntListpublic int size()
java.util.Collectionsize in interface Collection<Integer>size in interface List<Integer>size in class AbstractCollection<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 IntListsize in class AbstractIntListsize - the new size.public boolean isEmpty()
java.util.AbstractCollectionThis implementation returns size() == 0.
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 void getElements(int from,
int[] a,
int offset,
int length)
getElements in interface IntListgetElements in class AbstractIntListfrom - 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 IntListremoveElements in class AbstractIntListfrom - the start index (inclusive).to - the end index (exclusive).public void addElements(int index,
int[] a,
int offset,
int length)
addElements in interface IntListaddElements in class AbstractIntListindex - 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 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 IntCollectiontoArray in class AbstractIntCollectiona - if this array is big enough, it will be used to store this
collection.Collection.toArray(Object[])public boolean addAll(int index,
IntCollection c)
IntListaddAll in interface IntListaddAll in class AbstractIntListList.addAll(int,java.util.Collection)public boolean addAll(int index,
IntList l)
AbstractIntList
This implementation delegates to the type-specific version of
List.addAll(int, Collection).
addAll in interface IntListaddAll in class AbstractIntListList.add(int,Object)public boolean removeAll(IntCollection c)
IntCollectionremoveAll in interface IntCollectionremoveAll in class AbstractIntCollectionc - a type-specific collection.true if this collection changed as a result of the call.Collection.removeAll(Collection)public boolean removeAll(Collection<?> c)
java.util.AbstractCollectionThis implementation iterates over this collection, checking each element returned by the iterator in turn to see if it's contained in the specified collection. If it's so contained, it's removed from this collection with the iterator's remove method.
Note that this implementation will throw an UnsupportedOperationException if the iterator returned by the iterator method does not implement the remove method and this collection contains one or more elements in common with the specified collection.
removeAll in interface Collection<Integer>removeAll in interface List<Integer>removeAll in class AbstractCollection<Integer>c - collection containing elements to be removed from this collectionAbstractCollection.remove(Object),
AbstractCollection.contains(Object)public IntListIterator listIterator(int index)
AbstractIntListThis implementation is based on the random-access methods.
listIterator in interface IntListlistIterator in interface List<Integer>listIterator in class AbstractIntListindex - index of the first element to be returned from the
list iterator (by a call to next)List.listIterator(int)public IntArrayList clone()
java.lang.Objectx, the expression:
will be true, and that the expression:x.clone() != x
will bex.clone().getClass() == x.getClass()
true, but these are not absolute requirements.
While it is typically the case that:
will bex.clone().equals(x)
true, this is not an absolute requirement.
By convention, the returned object should be obtained by calling
super.clone. If a class and all of its superclasses (except
Object) obey this convention, it will be the case that
x.clone().getClass() == x.getClass().
By convention, the object returned by this method should be independent
of this object (which is being cloned). To achieve this independence,
it may be necessary to modify one or more fields of the object returned
by super.clone before returning it. Typically, this means
copying any mutable objects that comprise the internal "deep structure"
of the object being cloned and replacing the references to these
objects with references to the copies. If a class contains only
primitive fields or references to immutable objects, then it is usually
the case that no fields in the object returned by super.clone
need to be modified.
The method clone for class Object performs a
specific cloning operation. First, if the class of this object does
not implement the interface Cloneable, then a
CloneNotSupportedException is thrown. Note that all arrays
are considered to implement the interface Cloneable and that
the return type of the clone method of an array type T[]
is T[] where T is any reference or primitive type.
Otherwise, this method creates a new instance of the class of this
object and initializes all its fields with exactly the contents of
the corresponding fields of this object, as if by assignment; the
contents of the fields are not themselves cloned. Thus, this method
performs a "shallow copy" of this object, not a "deep copy" operation.
The class Object does not itself implement the interface
Cloneable, so calling the clone method on an object
whose class is Object will result in throwing an
exception at run time.
public boolean equals(IntArrayList l)
This method exists only for sake of efficiency. The implementation inherited from the abstract implementation would already work.
l - a type-specific array list.public int compareTo(IntArrayList l)
This method exists only for sake of efficiency. The implementation inherited from the abstract implementation would already work.
l - an array list.