org.apache.commons.collections.list
public class GrowthList extends AbstractSerializableListDecorator
List
to make it seamlessly grow when
indices larger than the list size are used on add and set,
avoiding most IndexOutOfBoundsExceptions.
This class avoids errors by growing when a set or add method would normally throw an IndexOutOfBoundsException. Note that IndexOutOfBoundsException IS returned for invalid negative indices.
Trying to set or add to an index larger than the size will cause the list
to grow (using null
elements). Clearly, care must be taken
not to use excessively large indices, as the internal list will grow to
match.
Trying to use any method other than add or set with an invalid index will call the underlying list and probably result in an IndexOutOfBoundsException.
Take care when using this list with null
values, as
null
is the value added when growing the list.
All sub-lists will access the underlying list directly, and will throw IndexOutOfBoundsExceptions.
This class differs from LazyList because here growth occurs on
set and add, where LazyList
grows on get. However, they
can be used together by decorating twice.
Since: Commons Collections 3.2
Version: $Revision: 155406 $ $Date: 2006-05-12 23:57:03 +0100 (Fri, 12 May 2006) $
See Also: LazyList
Constructor Summary | |
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GrowthList()
Constructor that uses an ArrayList internally. | |
GrowthList(int initialSize)
Constructor that uses an ArrayList internally.
| |
protected | GrowthList(List list)
Constructor that wraps (not copies).
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Method Summary | |
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void | add(int index, Object element)
Decorate the add method to perform the growth behaviour.
|
boolean | addAll(int index, Collection coll)
Decorate the addAll method to perform the growth behaviour.
|
static List | decorate(List list)
Factory method to create a growth list.
|
Object | set(int index, Object element)
Decorate the set method to perform the growth behaviour.
|
Parameters: initialSize the initial size of the ArrayList
Throws: IllegalArgumentException if initial size is invalid
Parameters: list the list to decorate, must not be null
Throws: IllegalArgumentException if list is null
If the requested index is greater than the current size, the list will
grow to the new size. Indices between the old size and the requested
size will be filled with null
.
If the index is less than the current size, the value will be added to the underlying list directly. If the index is less than zero, the underlying list is called, which will probably throw an IndexOutOfBoundsException.
Parameters: index the index to add at element the object to add at the specified index
Throws: UnsupportedOperationException if the underlying list doesn't implement set ClassCastException if the underlying list rejects the element IllegalArgumentException if the underlying list rejects the element
If the requested index is greater than the current size, the list will
grow to the new size. Indices between the old size and the requested
size will be filled with null
.
If the index is less than the current size, the values will be added to the underlying list directly. If the index is less than zero, the underlying list is called, which will probably throw an IndexOutOfBoundsException.
Parameters: index the index to add at coll the collection to add at the specified index
Returns: true if the list changed
Throws: UnsupportedOperationException if the underlying list doesn't implement set ClassCastException if the underlying list rejects the element IllegalArgumentException if the underlying list rejects the element
Parameters: list the list to decorate, must not be null
Throws: IllegalArgumentException if list is null
If the requested index is greater than the current size, the list will
grow to the new size. Indices between the old size and the requested
size will be filled with null
.
If the index is less than the current size, the value will be set onto the underlying list directly. If the index is less than zero, the underlying list is called, which will probably throw an IndexOutOfBoundsException.
Parameters: index the index to set element the object to set at the specified index
Returns: the object previously at that index
Throws: UnsupportedOperationException if the underlying list doesn't implement set ClassCastException if the underlying list rejects the element IllegalArgumentException if the underlying list rejects the element