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Préférences
Moteurs de recherche
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JavaTM 2 Platform Std. Ed. v1.6.0
java.util
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Method Summary | ||
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boolean |
add(E e)
Appends the specified element to the end of this list (optional operation). |
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void |
add(int index,
E element)
Inserts the specified element at the specified position in this list (optional operation). |
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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 (optional operation). |
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boolean |
addAll(int index,
Collection<? extends E> c)
Inserts all of the elements in the specified collection into this list at the specified position (optional operation). |
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void |
clear()
Removes all of the elements from this list (optional operation). |
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boolean |
contains(Object o)
Returns true if this list contains the specified element. |
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boolean |
containsAll(Collection<?> c)
Returns true if this list contains all of the elements of the specified collection. |
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boolean |
equals(Object o)
Compares the specified object with this list for equality. |
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E |
get(int index)
Returns the element at the specified position in this list. |
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int |
hashCode()
Returns the hash code value for this list. |
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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. |
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boolean |
isEmpty()
Returns true if this list contains no elements. |
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Iterator<E> |
iterator()
Returns an iterator over the elements in this list in proper sequence. |
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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. |
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ListIterator<E> |
listIterator()
Returns a list iterator over the elements in this list (in proper sequence). |
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ListIterator<E> |
listIterator(int index)
Returns a list iterator of the elements in this list (in proper sequence), starting at the specified position in this list. |
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E |
remove(int index)
Removes the element at the specified position in this list (optional operation). |
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boolean |
remove(Object o)
Removes the first occurrence of the specified element from this list, if it is present (optional operation). |
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boolean |
removeAll(Collection<?> c)
Removes from this list all of its elements that are contained in the specified collection (optional operation). |
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boolean |
retainAll(Collection<?> c)
Retains only the elements in this list that are contained in the specified collection (optional operation). |
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E |
set(int index,
E element)
Replaces the element at the specified position in this list with the specified element (optional operation). |
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int |
size()
Returns the number of elements in this list. |
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List<E> |
subList(int fromIndex,
int toIndex)
Returns a view of the portion of this list between the specified fromIndex, inclusive, and toIndex, exclusive. |
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Object[] |
toArray()
Returns an array containing all of the elements in this list in proper sequence (from first to last element). |
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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. |
Method Detail |
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int size()
size
in interface Collection<E>
boolean isEmpty()
isEmpty
in interface Collection<E>
boolean contains(Object o)
contains
in interface Collection<E>
o
- element whose presence in this list is to be tested
ClassCastException
- if the type of the specified element
is incompatible with this list (optional)
NullPointerException
- if the specified element is null and this
list does not permit null elements (optional)Iterator<E> iterator()
Object[] toArray()
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 even if this list is backed by an array). The caller is thus free to modify the returned array.
This method acts as bridge between array-based and collection-based APIs.
toArray
in interface Collection<E>
Arrays.asList(Object[])
<T> T[] toArray(T[] a)
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 list 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.)
Like the toArray()
method, this method acts as bridge between
array-based and collection-based APIs. Further, this method allows
precise control over the runtime type of the output array, and may,
under certain circumstances, be used to save allocation costs.
Suppose x is a list known to contain only strings. The following code can be used to dump the list into a newly allocated array of String:
String[] y = x.toArray(new String[0]);Note that toArray(new Object[0]) is identical in function to toArray().
toArray
in interface Collection<E>
a
- the array into which the elements of this list are to
be stored, if it is big enough; otherwise, a new array of the
same runtime type is allocated for this purpose.
ArrayStoreException
- if the runtime type of the specified array
is not a supertype of the runtime type of every element in
this list
NullPointerException
- if the specified array is nullboolean add(E e)
Lists that support this operation may place limitations on what elements may be added to this list. In particular, some lists will refuse to add null elements, and others will impose restrictions on the type of elements that may be added. List classes should clearly specify in their documentation any restrictions on what elements may be added.
add
in interface Collection<E>
e
- element to be appended to this list
Collection.add(E)
)
UnsupportedOperationException
- if the add operation
is not supported by this list
ClassCastException
- if the class of the specified element
prevents it from being added to this list
NullPointerException
- if the specified element is null and this
list does not permit null elements
IllegalArgumentException
- if some property of this element
prevents it from being added to this listboolean remove(Object o)
remove
in interface Collection<E>
o
- element to be removed from this list, if present
ClassCastException
- if the type of the specified element
is incompatible with this list (optional)
NullPointerException
- if the specified element is null and this
list does not permit null elements (optional)
UnsupportedOperationException
- if the remove operation
is not supported by this listboolean containsAll(Collection<?> c)
containsAll
in interface Collection<E>
c
- collection to be checked for containment in this list
ClassCastException
- if the types of one or more elements
in the specified collection are incompatible with this
list (optional)
NullPointerException
- if the specified collection contains one
or more null elements and this list does not permit null
elements (optional), or if the specified collection is nullcontains(Object)
boolean addAll(Collection<? extends E> c)
addAll
in interface Collection<E>
c
- collection containing elements to be added to this list
UnsupportedOperationException
- if the addAll operation
is not supported by this list
ClassCastException
- if the class of an element of the specified
collection prevents it from being added to this list
NullPointerException
- if the specified collection contains one
or more null elements and this list does not permit null
elements, or if the specified collection is null
IllegalArgumentException
- if some property of an element of the
specified collection prevents it from being added to this listadd(Object)
boolean addAll(int index, Collection<? extends E> c)
index
- index at which to insert the first element from the
specified collectionc
- collection containing elements to be added to this list
UnsupportedOperationException
- if the addAll operation
is not supported by this list
ClassCastException
- if the class of an element of the specified
collection prevents it from being added to this list
NullPointerException
- if the specified collection contains one
or more null elements and this list does not permit null
elements, or if the specified collection is null
IllegalArgumentException
- if some property of an element of the
specified collection prevents it from being added to this list
IndexOutOfBoundsException
- if the index is out of range
(index < 0 || index > size())boolean removeAll(Collection<?> c)
removeAll
in interface Collection<E>
c
- collection containing elements to be removed from this list
UnsupportedOperationException
- if the removeAll operation
is not supported by this list
ClassCastException
- if the class of an element of this list
is incompatible with the specified collection (optional)
NullPointerException
- if this list contains a null element and the
specified collection does not permit null elements (optional),
or if the specified collection is nullremove(Object)
,
contains(Object)
boolean retainAll(Collection<?> c)
retainAll
in interface Collection<E>
c
- collection containing elements to be retained in this list
UnsupportedOperationException
- if the retainAll operation
is not supported by this list
ClassCastException
- if the class of an element of this list
is incompatible with the specified collection (optional)
NullPointerException
- if this list contains a null element and the
specified collection does not permit null elements (optional),
or if the specified collection is nullremove(Object)
,
contains(Object)
void clear()
clear
in interface Collection<E>
UnsupportedOperationException
- if the clear operation
is not supported by this listboolean equals(Object o)
equals
in interface Collection<E>
equals
in class Object
o
- the object to be compared for equality with this list
Object.hashCode()
,
Hashtable
int hashCode()
int hashCode = 1; Iterator<E> i = list.iterator(); while (i.hasNext()) { E obj = i.next(); hashCode = 31*hashCode + (obj==null ? 0 : obj.hashCode()); }This ensures that list1.equals(list2) implies that list1.hashCode()==list2.hashCode() for any two lists, list1 and list2, as required by the general contract of
Object.hashCode()
.
hashCode
in interface Collection<E>
hashCode
in class Object
Object.equals(Object)
,
equals(Object)
E get(int index)
index
- index of the element to return
IndexOutOfBoundsException
- if the index is out of range
(index < 0 || index >= size())E set(int index, E element)
index
- index of the element to replaceelement
- element to be stored at the specified position
UnsupportedOperationException
- if the set operation
is not supported by this list
ClassCastException
- if the class of the specified element
prevents it from being added to this list
NullPointerException
- if the specified element is null and
this list does not permit null elements
IllegalArgumentException
- if some property of the specified
element prevents it from being added to this list
IndexOutOfBoundsException
- if the index is out of range
(index < 0 || index >= size())void add(int index, E element)
index
- index at which the specified element is to be insertedelement
- element to be inserted
UnsupportedOperationException
- if the add operation
is not supported by this list
ClassCastException
- if the class of the specified element
prevents it from being added to this list
NullPointerException
- if the specified element is null and
this list does not permit null elements
IllegalArgumentException
- if some property of the specified
element prevents it from being added to this list
IndexOutOfBoundsException
- if the index is out of range
(index < 0 || index > size())E remove(int index)
index
- the index of the element to be removed
UnsupportedOperationException
- if the remove operation
is not supported by this list
IndexOutOfBoundsException
- if the index is out of range
(index < 0 || index >= size())int indexOf(Object o)
o
- element to search for
ClassCastException
- if the type of the specified element
is incompatible with this list (optional)
NullPointerException
- if the specified element is null and this
list does not permit null elements (optional)int lastIndexOf(Object o)
o
- element to search for
ClassCastException
- if the type of the specified element
is incompatible with this list (optional)
NullPointerException
- if the specified element is null and this
list does not permit null elements (optional)ListIterator<E> listIterator()
ListIterator<E> listIterator(int index)
next
.
An initial call to previous
would
return the element with the specified index minus one.
index
- index of first element to be returned from the
list iterator (by a call to the next method)
IndexOutOfBoundsException
- if the index is out of range
(index < 0 || index > size())List<E> subList(int fromIndex, int toIndex)
This method eliminates the need for explicit range operations (of the sort that commonly exist for arrays). Any operation that expects a list can be used as a range operation by passing a subList view instead of a whole list. For example, the following idiom removes a range of elements from a list:
list.subList(from, to).clear();Similar idioms may be constructed for indexOf and lastIndexOf, and all of the algorithms in the Collections class can be applied to a subList.
The semantics of the list returned by this method become undefined if the backing list (i.e., this list) is structurally modified in any way other than via the returned list. (Structural modifications are those that change the size of this list, or otherwise perturb it in such a fashion that iterations in progress may yield incorrect results.)
fromIndex
- low endpoint (inclusive) of the subListtoIndex
- high endpoint (exclusive) of the subList
IndexOutOfBoundsException
- for an illegal endpoint index value
(fromIndex < 0 || toIndex > size ||
fromIndex > toIndex)