AutoPopulatingList

java.lang.Object
- org.springframework.util.AutoPopulatingList<E>

All Implemented Interfaces:

java.io.Serializable, java.lang.Iterable<E>, java.util.Collection<E>, java.util.List<E>
```
public class AutoPopulatingList<E>
extends java.lang.Object
implements java.util.List<E>, java.io.Serializable
```
Simple <code>List</code> wrapper class that allows for elements to be automatically populated as they are requested. This is particularly useful for data binding to <code>Lists</code>, allowing for elements to be created and added to the <code>List</code> in a "just in time" fashion.
Note: This class is not thread-safe. To create a thread-safe version, use the Collections.synchronizedList(java.util.List<T>) utility methods.
Inspired by LazyList from Commons Collections.

Since:

2.0

Author:

Rob Harrop, Juergen Hoeller

See Also:

Serialized Form

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`static interface`	`AutoPopulatingList.ElementFactory<E>` Factory interface for creating elements for an index-based access data structure such as a <code>List</code>.
`static class`	`AutoPopulatingList.ElementInstantiationException` Exception to be thrown from ElementFactory.
`private static class`	`AutoPopulatingList.ReflectiveElementFactory<E>` Reflective implementation of the ElementFactory interface, using `Class.newInstance()` on a given element class.

Field Summary

Fields
Modifier and Type	Field and Description
`private java.util.List<E>`	`backingList` The <code>List</code> that all operations are eventually delegated to.
`private AutoPopulatingList.ElementFactory<E>`	`elementFactory` The `AutoPopulatingList.ElementFactory` to use to create new <code>List</code> elements on demand.

Constructor Summary

Constructors
Constructor and Description
`AutoPopulatingList(AutoPopulatingList.ElementFactory<E> elementFactory)` Creates a new `AutoPopulatingList` that is backed by a standard <code>ArrayList</code> and creates new elements on demand using the supplied `AutoPopulatingList.ElementFactory`.
`AutoPopulatingList(java.lang.Class<? extends E> elementClass)` Creates a new `AutoPopulatingList` that is backed by a standard <code>ArrayList</code> and adds new instances of the supplied <code>element Class</code> to the backing <code>List</code> on demand.
`AutoPopulatingList(java.util.List<E> backingList, AutoPopulatingList.ElementFactory<E> elementFactory)` Creates a new `AutoPopulatingList` that is backed by the supplied <code>List</code> and creates new elements on demand using the supplied `AutoPopulatingList.ElementFactory`.
`AutoPopulatingList(java.util.List<E> backingList, java.lang.Class<? extends E> elementClass)` Creates a new `AutoPopulatingList` that is backed by the supplied <code>List</code> and adds new instances of the supplied <code>element Class</code> to the backing <code>List</code> on demand.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`add(E o)`
`void`	`add(int index, E element)`
`boolean`	`addAll(java.util.Collection<? extends E> c)`
`boolean`	`addAll(int index, java.util.Collection<? extends E> c)`
`void`	`clear()`
`boolean`	`contains(java.lang.Object o)`
`boolean`	`containsAll(java.util.Collection c)`
`boolean`	`equals(java.lang.Object other)`
`E`	`get(int index)` Get the element at the supplied index, creating it if there is no element at that index.
`int`	`hashCode()`
`int`	`indexOf(java.lang.Object o)`
`boolean`	`isEmpty()`
`java.util.Iterator<E>`	`iterator()`
`int`	`lastIndexOf(java.lang.Object o)`
`java.util.ListIterator<E>`	`listIterator()`
`java.util.ListIterator<E>`	`listIterator(int index)`
`E`	`remove(int index)`
`boolean`	`remove(java.lang.Object o)`
`boolean`	`removeAll(java.util.Collection<?> c)`
`boolean`	`retainAll(java.util.Collection<?> c)`
`E`	`set(int index, E element)`
`int`	`size()`
`java.util.List<E>`	`subList(int fromIndex, int toIndex)`
`java.lang.Object[]`	`toArray()`
`<T> T[]`	`toArray(T[] a)`

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.List
replaceAll, sort, spliterator

Methods inherited from interface java.util.Collection
parallelStream, removeIf, stream

Methods inherited from interface java.lang.Iterable
forEach

- Field Detail
  - backingList
```
private final java.util.List<E> backingList
```
    The <code>List</code> that all operations are eventually delegated to.
  - elementFactory
```
private final AutoPopulatingList.ElementFactory<E> elementFactory
```
    The AutoPopulatingList.ElementFactory to use to create new <code>List</code> elements on demand.
- Constructor Detail
  - AutoPopulatingList
```
public AutoPopulatingList(java.lang.Class<? extends E> elementClass)
```
    Creates a new AutoPopulatingList that is backed by a standard <code>ArrayList</code> and adds new instances of the supplied <code>element Class</code> to the backing <code>List</code> on demand.
  - AutoPopulatingList
```
public AutoPopulatingList(java.util.List<E> backingList,
                          java.lang.Class<? extends E> elementClass)
```
    Creates a new AutoPopulatingList that is backed by the supplied <code>List</code> and adds new instances of the supplied <code>element Class</code> to the backing <code>List</code> on demand.
  - AutoPopulatingList
```
public AutoPopulatingList(AutoPopulatingList.ElementFactory<E> elementFactory)
```
    Creates a new AutoPopulatingList that is backed by a standard <code>ArrayList</code> and creates new elements on demand using the supplied AutoPopulatingList.ElementFactory.
  - AutoPopulatingList
```
public AutoPopulatingList(java.util.List<E> backingList,
                          AutoPopulatingList.ElementFactory<E> elementFactory)
```
    Creates a new AutoPopulatingList that is backed by the supplied <code>List</code> and creates new elements on demand using the supplied AutoPopulatingList.ElementFactory.
- Method Detail
  - add
```
public void add(int index,
                E element)
```
    Specified by:
    
    add in interface java.util.List<E>
  - add
```
public boolean add(E o)
```
    Specified by:
    
    add in interface java.util.Collection<E>
    
    Specified by:
    
    add in interface java.util.List<E>
  - addAll
```
public boolean addAll(java.util.Collection<? extends E> c)
```
    Specified by:
    
    addAll in interface java.util.Collection<E>
    
    Specified by:
    
    addAll in interface java.util.List<E>
  - addAll
```
public boolean addAll(int index,
                      java.util.Collection<? extends E> c)
```
    Specified by:
    
    addAll in interface java.util.List<E>
  - clear
```
public void clear()
```
    Specified by:
    
    clear in interface java.util.Collection<E>
    
    Specified by:
    
    clear in interface java.util.List<E>
  - contains
```
public boolean contains(java.lang.Object o)
```
    Specified by:
    
    contains in interface java.util.Collection<E>
    
    Specified by:
    
    contains in interface java.util.List<E>
  - containsAll
```
public boolean containsAll(java.util.Collection c)
```
    Specified by:
    
    containsAll in interface java.util.Collection<E>
    
    Specified by:
    
    containsAll in interface java.util.List<E>
  - get
```
public E get(int index)
```
    Get the element at the supplied index, creating it if there is no element at that index.
    
    Specified by:
    
    get in interface java.util.List<E>
  - indexOf
```
public int indexOf(java.lang.Object o)
```
    Specified by:
    
    indexOf in interface java.util.List<E>
  - isEmpty
```
public boolean isEmpty()
```
    Specified by:
    
    isEmpty in interface java.util.Collection<E>
    
    Specified by:
    
    isEmpty in interface java.util.List<E>
  - iterator
```
public java.util.Iterator<E> iterator()
```
    Specified by:
    
    iterator in interface java.lang.Iterable<E>
    
    Specified by:
    
    iterator in interface java.util.Collection<E>
    
    Specified by:
    
    iterator in interface java.util.List<E>
  - lastIndexOf
```
public int lastIndexOf(java.lang.Object o)
```
    Specified by:
    
    lastIndexOf in interface java.util.List<E>
  - listIterator
```
public java.util.ListIterator<E> listIterator()
```
    Specified by:
    
    listIterator in interface java.util.List<E>
  - listIterator
```
public java.util.ListIterator<E> listIterator(int index)
```
    Specified by:
    
    listIterator in interface java.util.List<E>
  - remove
```
public E remove(int index)
```
    Specified by:
    
    remove in interface java.util.List<E>
  - remove
```
public boolean remove(java.lang.Object o)
```
    Specified by:
    
    remove in interface java.util.Collection<E>
    
    Specified by:
    
    remove in interface java.util.List<E>
  - removeAll
```
public boolean removeAll(java.util.Collection<?> c)
```
    Specified by:
    
    removeAll in interface java.util.Collection<E>
    
    Specified by:
    
    removeAll in interface java.util.List<E>
  - retainAll
```
public boolean retainAll(java.util.Collection<?> c)
```
    Specified by:
    
    retainAll in interface java.util.Collection<E>
    
    Specified by:
    
    retainAll in interface java.util.List<E>
  - set
```
public E set(int index,
             E element)
```
    Specified by:
    
    set in interface java.util.List<E>
  - size
```
public int size()
```
    Specified by:
    
    size in interface java.util.Collection<E>
    
    Specified by:
    
    size in interface java.util.List<E>
  - subList
```
public java.util.List<E> subList(int fromIndex,
                                 int toIndex)
```
    Specified by:
    
    subList in interface java.util.List<E>
  - toArray
```
public java.lang.Object[] toArray()
```
    Specified by:
    
    toArray in interface java.util.Collection<E>
    
    Specified by:
    
    toArray in interface java.util.List<E>
  - toArray
```
public <T> T[] toArray(T[] a)
```
    Specified by:
    
    toArray in interface java.util.Collection<E>
    
    Specified by:
    
    toArray in interface java.util.List<E>
  - equals
```
public boolean equals(java.lang.Object other)
```
    Specified by:
    
    equals in interface java.util.Collection<E>
    
    Specified by:
    
    equals in interface java.util.List<E>
    
    Overrides:
    
    equals in class java.lang.Object
  - hashCode
```
public int hashCode()
```
    Specified by:
    
    hashCode in interface java.util.Collection<E>
    
    Specified by:
    
    hashCode in interface java.util.List<E>
    
    Overrides:
    
    hashCode in class java.lang.Object

Class AutoPopulatingList<E>

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.List

Methods inherited from interface java.util.Collection

Methods inherited from interface java.lang.Iterable

Field Detail

backingList

elementFactory

Constructor Detail

AutoPopulatingList

AutoPopulatingList

AutoPopulatingList

AutoPopulatingList

Method Detail

add

add

addAll

addAll

clear

contains

containsAll

get

indexOf

isEmpty

iterator

lastIndexOf

listIterator

listIterator

remove

remove

removeAll

retainAll

set

size

subList

toArray

toArray

equals

hashCode