java.util.ArrayList<E>
ArrayList is an implementation of List, backed by an array. All optional
operations are supported, adding, removing, and replacing. The elements can
be any objects.
Summary
Public Constructors
Public Methods
Protected Methods
add,
add,
addAll,
clear,
equals,
get,
hashCode,
indexOf,
iterator,
lastIndexOf,
listIterator,
listIterator,
remove,
removeRange,
set,
subList
add,
addAll,
clear,
contains,
containsAll,
isEmpty,
iterator,
remove,
removeAll,
retainAll,
size,
toArray,
toArray,
toString
clone,
equals,
finalize,
getClass,
hashCode,
notify,
notifyAll,
toString,
wait,
wait,
wait
add,
addAll,
clear,
contains,
containsAll,
equals,
hashCode,
isEmpty,
iterator,
remove,
removeAll,
retainAll,
size,
toArray,
toArray
Methods inherited
from interface
java.util.List
add,
add,
addAll,
addAll,
clear,
contains,
containsAll,
equals,
get,
hashCode,
indexOf,
isEmpty,
iterator,
lastIndexOf,
listIterator,
listIterator,
remove,
remove,
removeAll,
retainAll,
set,
size,
subList,
toArray,
toArray
Details
Public Constructors
public
ArrayList()
Constructs a new instance of ArrayList with zero capacity.
public
ArrayList(int capacity)
Constructs a new instance of ArrayList with the specified capacity.
Parameters
capacity
| the initial capacity of this ArrayList
|
public
ArrayList(Collection<? extends E> collection)
Constructs a new instance of ArrayList containing the elements in the
specified collection. The ArrayList will have an initial capacity which
is 110% of the size of the collection. The order of the elements in this
ArrayList is the order they are returned by the collection iterator.
Parameters
collection
| the collection of elements to add
|
Public Methods
public
void
add(int location, E object)
Inserts the specified object into this ArrayList at the specified
location. The object is inserted before any previous element at the
specified location. If the location is equal to the size of this
ArrayList, the object is added at the end.
Parameters
location
| the index at which to insert |
object
| the object to add |
public
boolean
add(E object)
Adds the specified object at the end of this ArrayList.
public
boolean
addAll(int location, Collection<? extends E> collection)
Inserts the objects in the specified Collection at the specified location
in this ArrayList. The objects are added in the order they are returned
from the Collection iterator.
Parameters
location
| the index at which to insert |
collection
| the Collection of objects |
Returns
- true if this ArrayList is modified, false otherwise
public
boolean
addAll(Collection<? extends E> collection)
Adds the objects in the specified Collection to this ArrayList.
Parameters
collection
| the Collection of objects |
Returns
- true if this ArrayList is modified, false otherwise
public
void
clear()
Removes all elements from this ArrayList, leaving it empty.
public
Object
clone()
Returns a new ArrayList with the same elements, size and capacity as this
ArrayList.
Returns
- a shallow copy of this ArrayList
public
boolean
contains(Object object)
Searches this ArrayList for the specified object.
Parameters
object
| the object to search for |
Returns
- true if
object
is an element of this ArrayList,
false otherwise
public
void
ensureCapacity(int minimumCapacity)
Ensures that this ArrayList can hold the specified number of elements
without growing.
Parameters
minimumCapacity
| the minimum number of elements that this ArrayList will hold
before growing
|
public
E
get(int location)
Returns the element at the specified location in this ArrayList.
Parameters
location
| the index of the element to return |
Returns
- the element at the specified index
public
int
indexOf(Object object)
Searches this ArrayList for the specified object and returns the index of
the first occurrence.
Parameters
object
| the object to search for |
Returns
- the index of the first occurrence of the object
public
boolean
isEmpty()
Returns if this ArrayList has no elements, a size of zero.
Returns
- true if this ArrayList has no elements, false otherwise
public
int
lastIndexOf(Object object)
Searches this ArrayList for the specified object and returns the index of
the last occurrence.
Parameters
object
| the object to search for |
Returns
- the index of the last occurrence of the object
public
E
remove(int location)
Removes the object at the specified location from this ArrayList.
Parameters
location
| the index of the object to remove |
public
boolean
remove(Object object)
Removes the first occurrence of the specified object from this
Collection. This operation traverses over the collection, looking
for the specified object. Once the object is found, the object will
be removed from the collection using the iterator's remove method.
This collection will throw an UnsupportedOperationException if the
iterator returned does not implement remove method, and the specified
object is in this collection.
Parameters
object
| the object to remove |
Returns
- true if this Collection is modified, false otherwise
public
E
set(int location, E object)
Replaces the element at the specified location in this ArrayList with the
specified object.
Parameters
location
| the index at which to put the specified object |
object
| the object to add |
Returns
- the previous element at the index
public
int
size()
Returns the number of elements in this ArrayList.
Returns
- the number of elements in this ArrayList
public
T[]
toArray(T[] contents)
Returns an array containing all elements contained in this ArrayList. If
the specified array is large enough to hold the elements, the specified
array is used, otherwise an array of the same type is created. If the
specified array is used and is larger than this ArrayList, the array
element following the collection elements is set to null.
Returns
- an array of the elements from this ArrayList
Throws
ArrayStoreException
| when the type of an element in this ArrayList cannot be
stored in the type of the specified array
|
public
Object[]
toArray()
Returns a new array containing all elements contained in this ArrayList.
Returns
- an array of the elements from this ArrayList
public
void
trimToSize()
Sets the capacity of this ArrayList to be the same as the size.
Protected Methods
protected
void
removeRange(int start, int end)
Removes the objects in the specified range from the start to the end, but
not including the end index.
Parameters
start
| the index at which to start removing |
end
| the index one past the end of the range to remove |