Decorates another
List
to create objects in the list on demand.
When the
#get(int) method is called with an index greater than
the size of the list, the list will automatically grow in size and return
a new object from the specified factory. The gaps will be filled by null.
If a get method call encounters a null, it will be replaced with a new
object from the factory. Thus this list is unsuitable for storing null
objects.
For instance:
Factory factory = new Factory() {
public Object create() {
return new Date();
}
}
List lazy = LazyList.decorate(new ArrayList(), factory);
Object obj = lazy.get(3);
After the above code is executed,
obj
will contain
a new
Date
instance. Furthermore, that
Date
instance is the fourth element in the list. The first, second,
and third element are all set to
null
.
This class differs from
GrowthList because here growth occurs on
get, where GrowthList
grows on set and add. However, they
could easily be used together by decorating twice.
This class is Serializable from Commons Collections 3.1.