| sun.awt.util.IdentityArrayList
| IdentityArrayList | | public class IdentityArrayList extends AbstractList implements List<E>,RandomAccess(Code) | | Resizable-array implementation of the List interface. Implements
all optional list operations, and permits all elements, including
null. In addition to implementing the List interface,
this class provides methods to manipulate the size of the array that is
used internally to store the list. (This class is roughly equivalent to
Vector, except that it is unsynchronized.)
The size, isEmpty, get, set,
iterator, and listIterator operations run in constant
time. The add operation runs in amortized constant time,
that is, adding n elements requires O(n) time. All of the other operations
run in linear time (roughly speaking). The constant factor is low compared
to that for the LinkedList implementation.
Each IdentityArrayList instance has a capacity. The capacity is
the size of the array used to store the elements in the list. It is always
at least as large as the list size. As elements are added to an IdentityArrayList,
its capacity grows automatically. The details of the growth policy are not
specified beyond the fact that adding an element has constant amortized
time cost.
An application can increase the capacity of an IdentityArrayList instance
before adding a large number of elements using the ensureCapacity
operation. This may reduce the amount of incremental reallocation.
Note that this implementation is not synchronized.
If multiple threads access an IdentityArrayList instance concurrently,
and at least one of the threads modifies the list structurally, it
must be synchronized externally. (A structural modification is
any operation that adds or deletes one or more elements, or explicitly
resizes the backing array; merely setting the value of an element is not
a structural modification.) This is typically accomplished by
synchronizing on some object that naturally encapsulates the list.
If no such object exists, the list should be "wrapped" using the
Collections.synchronizedList Collections.synchronizedList method. This is best done at creation time, to prevent accidental
unsynchronized access to the list:
List list = Collections.synchronizedList(new IdentityArrayList(...));
The iterators returned by this class's iterator and
listIterator methods are fail-fast: if the list is
structurally modified at any time after the iterator is created, in any way
except through the iterator's own remove or add methods,
the iterator will throw a
ConcurrentModificationException . Thus, in
the face of concurrent modification, the iterator fails quickly and cleanly,
rather than risking arbitrary, non-deterministic behavior at an undetermined
time in the future.
Note that the fail-fast behavior of an iterator cannot be guaranteed
as it is, generally speaking, impossible to make any hard guarantees in the
presence of unsynchronized concurrent modification. Fail-fast iterators
throw ConcurrentModificationException on a best-effort basis.
Therefore, it would be wrong to write a program that depended on this
exception for its correctness: the fail-fast behavior of iterators
should be used only to detect bugs.
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| Constructor Summary | |
| public | IdentityArrayList(int initialCapacity)
Constructs an empty list with the specified initial capacity. | | public | IdentityArrayList()
Constructs an empty list with an initial capacity of ten. | | public | IdentityArrayList(Collection<? extends E> c)
Constructs a list containing the elements of the specified
collection, in the order they are returned by the collection's
iterator. |
| Method Summary | |
| public boolean | add(E e)
Appends the specified element to the end of this list. | | public void | add(int index, E element)
Inserts the specified element at the specified position in this
list. | | public boolean | addAll(Collection<? extends E> c)
Appends all of the elements in the specified collection to the end of
this list, in the order that they are returned by the
specified collection's Iterator. | | public boolean | addAll(int index, Collection<? extends E> c)
Inserts all of the elements in the specified collection into this
list, starting at the specified position. | | public void | clear()
Removes all of the elements from this list. | | public boolean | contains(Object o)
Returns true if this list contains the specified element. | | public void | ensureCapacity(int minCapacity)
Increases the capacity of this IdentityArrayList instance, if
necessary, to ensure that it can hold at least the number of elements
specified by the minimum capacity argument. | | public E | get(int index)
Returns the element at the specified position in this list. | | public int | indexOf(Object o)
Returns the index of the first occurrence of the specified element
in this list, or -1 if this list does not contain the element. | | public boolean | isEmpty()
Returns true if this list contains no elements. | | public int | lastIndexOf(Object o)
Returns the index of the last occurrence of the specified element
in this list, or -1 if this list does not contain the element. | | public E | remove(int index)
Removes the element at the specified position in this list. | | public boolean | remove(Object o)
Removes the first occurrence of the specified element from this list,
if it is present. | | protected void | removeRange(int fromIndex, int toIndex)
Removes from this list all of the elements whose index is between
fromIndex, inclusive, and toIndex, exclusive. | | public E | set(int index, E element)
Replaces the element at the specified position in this list with
the specified element. | | public int | size()
Returns the number of elements in this list. | | public Object[] | toArray()
Returns an array containing all of the elements in this list
in proper sequence (from first to last element).
The returned array will be "safe" in that no references to it are
maintained by this list. | | public T[] | toArray(T[] a)
Returns an array containing all of the elements in this list in proper
sequence (from first to last element); the runtime type of the returned
array is that of the specified array. | | public void | trimToSize()
Trims the capacity of this IdentityArrayList instance to be the
list's current size. |
| IdentityArrayList | | public IdentityArrayList(int initialCapacity)(Code) | | Constructs an empty list with the specified initial capacity.
Parameters:
initialCapacity - the initial capacity of the list
exception:
IllegalArgumentException - if the specified initial capacityis negative |
| IdentityArrayList | | public IdentityArrayList()(Code) | | Constructs an empty list with an initial capacity of ten.
|
| IdentityArrayList | | public IdentityArrayList(Collection<? extends E> c)(Code) | | Constructs a list containing the elements of the specified
collection, in the order they are returned by the collection's
iterator.
Parameters:
c - the collection whose elements are to be placed into this list
throws:
NullPointerException - if the specified collection is null |
| add | | public boolean add(E e)(Code) | | Appends the specified element to the end of this list.
Parameters:
e - element to be appended to this list true (as specified by Collection.add) |
| add | | public void add(int index, E element)(Code) | | Inserts the specified element at the specified position in this
list. Shifts the element currently at that position (if any) and
any subsequent elements to the right (adds one to their indices).
Parameters:
index - index at which the specified element is to be inserted
Parameters:
element - element to be inserted
throws:
IndexOutOfBoundsException - |
| addAll | | public boolean addAll(Collection<? extends E> c)(Code) | | Appends all of the elements in the specified collection to the end of
this list, in the order that they are returned by the
specified collection's Iterator. The behavior of this operation is
undefined if the specified collection is modified while the operation
is in progress. (This implies that the behavior of this call is
undefined if the specified collection is this list, and this
list is nonempty.)
Parameters:
c - collection containing elements to be added to this list true if this list changed as a result of the call
throws:
NullPointerException - if the specified collection is null |
| addAll | | public boolean addAll(int index, Collection<? extends E> c)(Code) | | Inserts all of the elements in the specified collection into this
list, starting at the specified position. Shifts the element
currently at that position (if any) and any subsequent elements to
the right (increases their indices). The new elements will appear
in the list in the order that they are returned by the
specified collection's iterator.
Parameters:
index - index at which to insert the first element from thespecified collection
Parameters:
c - collection containing elements to be added to this list true if this list changed as a result of the call
throws:
IndexOutOfBoundsException -
throws:
NullPointerException - if the specified collection is null |
| clear | | public void clear()(Code) | | Removes all of the elements from this list. The list will
be empty after this call returns.
|
| contains | | public boolean contains(Object o)(Code) | | Returns true if this list contains the specified element.
More formally, returns true if and only if this list contains
at least one element e such that
(o==null ? e==null : o == e).
Parameters:
o - element whose presence in this list is to be tested true if this list contains the specified element |
| ensureCapacity | | public void ensureCapacity(int minCapacity)(Code) | | Increases the capacity of this IdentityArrayList instance, if
necessary, to ensure that it can hold at least the number of elements
specified by the minimum capacity argument.
Parameters:
minCapacity - the desired minimum capacity |
| get | | public E get(int index)(Code) | | Returns the element at the specified position in this list.
Parameters:
index - index of the element to return the element at the specified position in this list
throws:
IndexOutOfBoundsException - |
| indexOf | | public int indexOf(Object o)(Code) | | 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 index i such that
(o==null ? get(i)==null : o == get(i)),
or -1 if there is no such index.
|
| isEmpty | | public boolean isEmpty()(Code) | | Returns true if this list contains no elements.
true if this list contains no elements |
| lastIndexOf | | public int lastIndexOf(Object o)(Code) | | 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 index i such that
(o==null ? get(i)==null : o == get(i)),
or -1 if there is no such index.
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| remove | | public E remove(int index)(Code) | | Removes the element at the specified position in this list.
Shifts any subsequent elements to the left (subtracts one from their
indices).
Parameters:
index - the index of the element to be removed the element that was removed from the list
throws:
IndexOutOfBoundsException - |
| remove | | public boolean remove(Object o)(Code) | | Removes the first occurrence of the specified element from this list,
if it is present. If the list does not contain the element, it is
unchanged. More formally, removes the element with the lowest index
i such that
(o==null ? get(i)==null : o == get(i))
(if such an element exists). Returns true if this list
contained the specified element (or equivalently, if this list
changed as a result of the call).
Parameters:
o - element to be removed from this list, if present true if this list contained the specified element |
| removeRange | | protected void removeRange(int fromIndex, int toIndex)(Code) | | Removes from this list all of the elements whose index is between
fromIndex, inclusive, and toIndex, exclusive.
Shifts any succeeding elements to the left (reduces their index).
This call shortens the list by (toIndex - fromIndex) elements.
(If toIndex==fromIndex, this operation has no effect.)
Parameters:
fromIndex - index of first element to be removed
Parameters:
toIndex - index after last element to be removed
throws:
IndexOutOfBoundsException - if fromIndex or toIndex out ofrange (fromIndex < 0 || fromIndex >= size() || toIndex> size() || toIndex < fromIndex) |
| set | | public E set(int index, E element)(Code) | | Replaces the element at the specified position in this list with
the specified element.
Parameters:
index - index of the element to replace
Parameters:
element - element to be stored at the specified position the element previously at the specified position
throws:
IndexOutOfBoundsException - |
| size | | public int size()(Code) | | Returns the number of elements in this list.
the number of elements in this list |
| toArray | | public Object[] toArray()(Code) | | Returns an array containing all of the elements in this list
in proper sequence (from first to last element).
The returned array will be "safe" in that no references to it are
maintained by this list. (In other words, this method must allocate
a new array). The caller is thus free to modify the returned array.
This method acts as bridge between array-based and collection-based
APIs.
an array containing all of the elements in this list inproper sequence |
| toArray | | public T[] toArray(T[] a)(Code) | | Returns an array containing all of the elements in this list in proper
sequence (from first to last element); the runtime type of the returned
array is that of the specified array. If the list fits in the
specified array, it is returned therein. Otherwise, a new array is
allocated with the runtime type of the specified array and the size of
this list.
If the list fits in the specified array with room to spare
(i.e., the array has more elements than the list), the element in
the array immediately following the end of the collection is set to
null. (This is useful in determining the length of the
list only if the caller knows that the list does not contain
any null elements.)
Parameters:
a - the array into which the elements of the list are tobe stored, if it is big enough; otherwise, a new array of thesame runtime type is allocated for this purpose. an array containing the elements of the list
throws:
ArrayStoreException - if the runtime type of the specified arrayis not a supertype of the runtime type of every element inthis list
throws:
NullPointerException - if the specified array is null |
| trimToSize | | public void trimToSize()(Code) | | Trims the capacity of this IdentityArrayList instance to be the
list's current size. An application can use this operation to minimize
the storage of an IdentityArrayList instance.
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