java.lang.Object | +--java.util.AbstractCollection | +--java.util.AbstractListAll Implemented Interfaces:
int | modCount A count of the number of structural modifications that have been made to the list (that is, insertions and removals). |
AbstractList() The main constructor, for use by subclasses. |
void | add(int index, java.lang.Object o) Insert an element into the list at a given position (optional operation). |
boolean | add(java.lang.Object o) Add an element to the end of the list (optional operation). |
boolean | addAll(int index, java.util.Collection c) Insert the contents of a collection into the list at a given position (optional operation). |
void | clear() Clear the list, such that a subsequent call to isEmpty() would return true (optional operation). |
boolean | equals(java.lang.Object o) Test whether this list is equal to another object. |
java.lang.Object | get(int index) Returns the elements at the specified position in the list. |
int | hashCode() Obtains a hash code for this list. |
int | indexOf(java.lang.Object o) Obtain the first index at which a given object is to be found in this list. |
java.util.Iterator | iterator() Obtain an Iterator over this list, whose sequence is the list order. |
int | lastIndexOf(java.lang.Object o) Obtain the last index at which a given object is to be found in this list. |
java.util.ListIterator | listIterator() Obtain a ListIterator over this list, starting at the beginning. |
java.util.ListIterator | listIterator(final int index) Obtain a ListIterator over this list, starting at a given position. |
java.lang.Object | remove(int index) Remove the element at a given position in this list (optional operation). |
void | removeRange(int fromIndex, int toIndex) Remove a subsection of the list. |
java.lang.Object | set(int index, java.lang.Object o) Replace an element of this list with another object (optional operation). |
java.util.List | subList(int fromIndex, int toIndex) Obtain a List view of a subsection of this list, from fromIndex (inclusive) to toIndex (exclusive). |
protected int modCount
To make lists fail-fast, increment this field by just 1 in the
add(int, Object)
and remove(int)
methods.
Otherwise, this field may be ignored.
protected AbstractList()
public void add(int index, java.lang.Object o)
index
- the location to insert the itemo
- the object to insertUnsupportedOperationException
- if this list does not support the
add operationIndexOutOfBoundsException
- if index < 0 || index > size()ClassCastException
- if o cannot be added to this list due to its
typeIllegalArgumentException
- if o cannot be added to this list for
some other reasonpublic boolean add(java.lang.Object o)
add(size(), o);
, and will fail if that version does.
o
- the object to addUnsupportedOperationException
- if this list does not support the
add operationClassCastException
- if o cannot be added to this list due to its
typeIllegalArgumentException
- if o cannot be added to this list for
some other reasonpublic boolean addAll(int index, java.util.Collection c)
index
- the location to insert the collectionc
- the collection to insertUnsupportedOperationException
- if this list does not support the
addAll operationIndexOutOfBoundsException
- if index < 0 || index > size()ClassCastException
- if some element of c cannot be added to this
list due to its typeIllegalArgumentException
- if some element of c cannot be added
to this list for some other reasonNullPointerException
- if the specified collection is nullpublic void clear()
removeRange(0, size())
, so it will fail unless remove
or removeRange is overridden.
UnsupportedOperationException
- if this list does not support the
clear operationpublic boolean equals(java.lang.Object o)
l1.size() == l2.size()
, and for every integer n between 0
and l1.size() - 1
inclusive, l1.get(n) == null ?
l2.get(n) == null : l1.get(n).equals(l2.get(n))
.
This implementation returns true if the object is this, or false if the object is not a List. Otherwise, it iterates over both lists (with iterator()), returning false if two elements compare false or one list is shorter, and true if the iteration completes successfully.
o
- the object to test for equality with this listpublic Object get(int index)
index
- the element to returnIndexOutOfBoundsException
- if index < 0 || index >= size()public int hashCode()
hashCode = 1; Iterator i = list.iterator(); while (i.hasNext()) { Object obj = i.next(); hashCode = 31 * hashCode + (obj == null ? 0 : obj.hashCode()); }This ensures that the general contract of Object.hashCode() is adhered to.
public int indexOf(java.lang.Object o)
o
- the object to search foro == null ? get(n) == null :
o.equals(get(n))
, or -1 if there is no such indexpublic Iterator iterator()
return listIterator(0)
.
public int lastIndexOf(java.lang.Object o)
o
- o == null ? get(n) == null
: o.equals(get(n))
, or -1 if there is no such indexpublic ListIterator listIterator()
public ListIterator listIterator(final int index)
This implementation uses size(), get(int), set(int, Object), add(int, Object), and remove(int) of the backing list, and does not support remove, set, or add unless the list does. This implementation is fail-fast if you correctly maintain modCount.
index
- the position, between 0 and size() inclusive, to begin the
iteration fromIndexOutOfBoundsException
- if index < 0 || index > size()public Object remove(int index)
index
- the position within the list of the object to removeUnsupportedOperationException
- if this list does not support the
remove operationIndexOutOfBoundsException
- if index < 0 || index >= size()protected void removeRange(int fromIndex, int toIndex)
This implementation first checks for illegal or out of range arguments. It then obtains a ListIterator over the list using listIterator(fromIndex). It then calls next() and remove() on this iterator repeatedly, toIndex - fromIndex times.
fromIndex
- the index, inclusive, to remove from.toIndex
- the index, exclusive, to remove to.public Object set(int index, java.lang.Object o)
index
- the position within this list of the element to be replacedo
- the object to replace it withUnsupportedOperationException
- if this list does not support the
set operationIndexOutOfBoundsException
- if index < 0 || index >= size()ClassCastException
- if o cannot be added to this list due to its
typeIllegalArgumentException
- if o cannot be added to this list for
some other reasonpublic List subList(int fromIndex, int toIndex)
This implementation returns a subclass of AbstractList. It stores, in private fields, the offset and size of the sublist, and the expected modCount of the backing list. If the backing list implements RandomAccess, the sublist will also.
The subclass's set(int, Object)
, get(int)
,
add(int, Object)
, remove(int)
,
addAll(int, Collection)
and
removeRange(int, int)
methods all delegate to the
corresponding methods on the backing abstract list, after
bounds-checking the index and adjusting for the offset. The
addAll(Collection c)
method merely returns addAll(size, c).
The listIterator(int)
method returns a "wrapper object"
over a list iterator on the backing list, which is created with the
corresponding method on the backing list. The iterator()
method merely returns listIterator(), and the size()
method
merely returns the subclass's size field.
All methods first check to see if the actual modCount of the backing list is equal to its expected value, and throw a ConcurrentModificationException if it is not.
fromIndex
- the index that the returned list should start from
(inclusive)toIndex
- the index that the returned list should go to (exclusive)IndexOutOfBoundsException
- if fromIndex < 0
|| toIndex > size()IllegalArgumentException
- if fromIndex > toIndex
As recommended by Collection and List, the subclass should provide at least a no-argument and a Collection constructor. This class is not synchronized.