# Class DefaultListModel<E>

java.lang.Object
javax.swing.AbstractListModel<E>
javax.swing.DefaultListModel<E>

Type Parameters:
  `E` - the type of the elements of this model

All Implemented Interfaces:
  `Serializable, ListModel<E>`

public class DefaultListModel<E> extends AbstractListModel<E>
This class loosely implements the `java.util.Vector` API, in that it implements the 1.1.x version of `java.util.Vector`, has no collection class support, and notifies the `ListDataListener`s when changes occur. Presently it delegates to a `Vector`, in a future release it will be a real Collection implementation.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans has been added to the `java.beans` package. Please see `XMLEncoder`.

Since:
  1.2

## Field Summary

### Fields declared in class AbstractListModel

`listenerList`

## Constructor Summary

Constructors
Constructor
Description
`DefaultListModel()`
Constructs a `DefaultListModel`.

## Method Summary

Modifier and Type
Method
Description
`void`
`add(int index, E element)`
Inserts the specified element at the specified position in this list.
`void`
`addAll(int index, Collection<? extends E> c)`
Adds all of the elements present in the collection, starting from the specified index.
`void`
`addAll(Collection<? extends E> c)`
Adds all of the elements present in the collection to the list.
`void`
`addElement(E element)`
Adds the specified component to the end of this list.
`int`
`capacity()`
Returns the current capacity of this list.
`void`
`clear()`
Removes all of the elements from this list.
`boolean`
`contains(Object elem)`
Tests whether the specified object is a component in this list.
`void`
`copyInto(Object[] anArray)`
Copies the components of this list into the specified array.
`E`
`elementAt(int index)`
Returns the component at the specified index.
`Enumeration<E>`
`elements()`
Returns an enumeration of the components of this list.
`void`
`ensureCapacity(int minCapacity)`
Increases the capacity of this list, if necessary, to ensure that it can hold at least the number of components specified by the minimum capacity argument.
`E`
`firstElement()`
Returns the first component of this list.
`E`
`get(int index)`
Returns the element at the specified position in this list.
`E`
`getElementAt(int index)`
Returns the component at the specified index.
`int`
`getSize()`
Returns the number of components in this list.
`int`
`indexOf(Object elem)`
Searches for the first occurrence of `elem`.
`int`
`indexOf(Object elem, int index)`
Searches for the first occurrence of `elem`, beginning the search at `index`.
`void`
`insertElementAt(E element, int index)`
Inserts the specified element as a component in this list at the specified `index`.
`boolean`
`isEmpty()`
Tests whether this list has any components.
`E`
`lastElement()`
Returns the last component of the list.
`int`
`lastIndexOf(Object elem)`
Returns the index of the last occurrence of `elem`.
`int`
`lastIndexOf(Object elem, int index)`
Searches backwards for `elem`, starting from the specified index, and returns an index to it.
`E`
`remove(int index)`
Removes the element at the specified position in this list.
`void`
`removeAllElements()`
Removes all components from this list and sets its size to zero.
`boolean`
`removeElement(Object obj)`
Removes the first (lowest-indexed) occurrence of the argument from this list.
`void`
`removeElementAt(int index)`
Deletes the component at the specified index.
`void`
`removeRange(int fromIndex, int toIndex)`
Deletes the components at the specified range of indexes.
`E`
`set(int index, E element)`
Replaces the element at the specified position in this list with the specified element.
`void`
`setElementAt(E element, int index)`
Sets the component at the specified `index` of this list to be the specified element.
`void`
`setSize(int newSize)`
Sets the size of this list.
`int`
`size()`
Returns the number of components in this list.
`Object[]`
`toArray()`
Returns an array containing all of the elements in this list in the correct order.
`String`
`toString()`
Returns a string that displays and identifies this object's properties.
`void`
`trimToSize()`
Trims the capacity of this list to be the list's current size.

### Methods declared in class AbstractListModel

`addListDataListener, fireContentsChanged, fireIntervalAdded, fireIntervalRemoved, getListDataListeners, getListeners, removeListDataListener`

### Methods declared in class Object

`clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

## Constructor Details

### DefaultListModel

public DefaultListModel()
Constructs a `DefaultListModel`.

## Method Details

### getSize

public int getSize()
Returns the number of components in this list.

This method is identical to `size`, which implements the `List` interface defined in the 1.2 Collections framework. This method exists in conjunction with `setSize` so that `size` is identifiable as a JavaBean property.

Returns:
  the number of components in this list
See Also:
  - `size()`

### getElementAt

public E getElementAt(int index)
Returns the component at the specified index.

> Note: Although this method is not deprecated, the preferred method to use is `get(int)`, which implements the `List` interface defined in the 1.2 Collections framework.

Parameters:
  `index` - an index into this list
Returns:
  the component at the specified index
Throws:
  `ArrayIndexOutOfBoundsException` - if the `index` is negative or greater than the current size of this list
See Also:
  - `get(int)`

### copyInto

public void copyInto(Object[] anArray)
Copies the components of this list into the specified array. The array must be big enough to hold all the objects in this list, else an `IndexOutOfBoundsException` is thrown.

Parameters:
  `anArray` - the array into which the components get copied
See Also:
  - `Vector.copyInto(Object[])`

### trimToSize

public void trimToSize()
Trims the capacity of this list to be the list's current size.

See Also:
  - `Vector.trimToSize()`

### ensureCapacity

public void ensureCapacity(int minCapacity)
Increases the capacity of this list, if necessary, to ensure that it can hold at least the number of components specified by the minimum capacity argument.

Parameters:
  `minCapacity` - the desired minimum capacity
See Also:
  - `Vector.ensureCapacity(int)`

### setSize

public void setSize(int newSize)
Sets the size of this list.

Parameters:
  `newSize` - the new size of this list
See Also:
  - `Vector.setSize(int)`

### capacity

public int capacity()
Returns the current capacity of this list.

Returns:
  the current capacity
See Also:
  - `Vector.capacity()`

### size

public int size()
Returns the number of components in this list.

Returns:
  the number of components in this list
See Also:
  - `Vector.size()`

### isEmpty

public boolean isEmpty()
Tests whether this list has any components.

Returns:
  `true` if and only if this list has no components, that is, its size is zero; `false` otherwise
See Also:
  - `Vector.isEmpty()`

### elements

public Enumeration<E> elements()
Returns an enumeration of the components of this list.

Returns:
  an enumeration of the components of this list
See Also:
  - `Vector.elements()`

### contains

public boolean contains(Object elem)
Tests whether the specified object is a component in this list.

Parameters:
  `elem` - an object
Returns:
  `true` if the specified object is the same as a component in this list
See Also:
  - `Vector.contains(Object)`

### indexOf

public int indexOf(Object elem)
Searches for the first occurrence of `elem`.

Parameters:
  `elem` - an object
Returns:
  the index of the first occurrence of the argument in this list; returns `-1` if the object is not found
See Also:
  - `Vector.indexOf(Object)`

### indexOf

public int indexOf(Object elem, int index)
Searches for the first occurrence of `elem`, beginning the search at `index`.

Parameters:
  `elem` - the desired component
  `index` - the index from which to begin searching
Returns:
  the index where the first occurrence of `elem` is found after `index`; returns `-1` if the `elem` is not found in the list
See Also:
  - `Vector.indexOf(Object,int)`

### lastIndexOf

public int lastIndexOf(Object elem)
Returns the index of the last occurrence of `elem`.

Parameters:
  `elem` - the desired component
Returns:
  the index of the last occurrence of `elem` in the list; returns `elem` if the object is not found
See Also:
  - `Vector.lastIndexOf(Object)`

### lastIndexOf

public int lastIndexOf(Object elem, int index)
Searches backwards for `elem`, starting from the specified index, and returns an index to it.

Parameters:
  `elem` - the desired component
  `index` - the index to start searching from
Returns:
  the index of the last occurrence of the `elem` in this list at position less than `index`; returns `-1` if the object is not found
See Also:
  - `Vector.lastIndexOf(Object,int)`

### elementAt

public E elementAt(int index)
Returns the component at the specified index.

> Note: Although this method is not deprecated, the preferred method to use is `get(int)`, which implements the `List` interface defined in the 1.2 Collections framework.

Parameters:
  `index` - an index into this list
Returns:
  the component at the specified index
Throws:
  `ArrayIndexOutOfBoundsException` - if the index is negative or not less than the size of the list
See Also:
  - `get(int)`
  - `Vector.elementAt(int)`

### firstElement

public E firstElement()
Returns the first component of this list.

Returns:
  the first component of this list
Throws:
  `NoSuchElementException` - if this vector has no components
See Also:
  - `Vector.firstElement()`

### lastElement

public E lastElement()
Returns the last component of the list.

Returns:
  the last component of the list
Throws:
  `NoSuchElementException` - if this vector has no components
See Also:
  - `Vector.lastElement()`

### setElementAt

public void setElementAt(E element, int index)
Sets the component at the specified `index` of this list to be the specified element. The previous component at that position is discarded.

> Note: Although this method is not deprecated, the preferred method to use is `set(int,Object)`, which implements the `List` interface defined in the 1.2 Collections framework.

Parameters:
  `element` - what the component is to be set to
  `index` - the specified index
Throws:
  `ArrayIndexOutOfBoundsException` - if the index is invalid
See Also:
  - `set(int,Object)`
  - `Vector.setElementAt(Object,int)`

### removeElementAt

public void removeElementAt(int index)
Deletes the component at the specified index.

> Note: Although this method is not deprecated, the preferred method to use is `remove(int)`, which implements the `List` interface defined in the 1.2 Collections framework.

Parameters:
  `index` - the index of the object to remove
Throws:
  `ArrayIndexOutOfBoundsException` - if the index is invalid
See Also:
  - `remove(int)`
  - `Vector.removeElementAt(int)`

### insertElementAt

public void insertElementAt(E element, int index)
Inserts the specified element as a component in this list at the specified `index`.

> Note: Although this method is not deprecated, the preferred method to use is `add(int,Object)`, which implements the `List` interface defined in the 1.2 Collections framework.

Parameters:
  `element` - the component to insert
  `index` - where to insert the new component
Throws:
  `ArrayIndexOutOfBoundsException` - if the index was invalid
See Also:
  - `add(int,Object)`
  - `Vector.insertElementAt(Object,int)`

### addElement

public void addElement(E element)
Adds the specified component to the end of this list.

Parameters:
  `element` - the component to be added
See Also:
  - `Vector.addElement(Object)`

### removeElement

public boolean removeElement(Object obj)
Removes the first (lowest-indexed) occurrence of the argument from this list.

Parameters:
  `obj` - the component to be removed
Returns:
  `true` if the argument was a component of this list; `false` otherwise
See Also:
  - `Vector.removeElement(Object)`

### removeAllElements

public void removeAllElements()
Removes all components from this list and sets its size to zero.

> Note: Although this method is not deprecated, the preferred method to use is `clear`, which implements the `List` interface defined in the 1.2 Collections framework.

See Also:
  - `clear()`
  - `Vector.removeAllElements()`

### toString

public String toString()
Returns a string that displays and identifies this object's properties.

Overrides:
  `toString` in class `Object`
Returns:
  a String representation of this object

### toArray

public Object[] toArray()
Returns an array containing all of the elements in this list in the correct order.

Returns:
  an array containing the elements of the list
See Also:
  - `Vector.toArray()`

### get

public E get(int index)
Returns the element at the specified position in this list.

Parameters:
  `index` - index of element to return
Returns:
  the element at the specified position in this list
Throws:
  `ArrayIndexOutOfBoundsException` - if the index is out of range (`index &lt; 0 || index &gt;= size()`)

### set

public E set(int index, E element)
Replaces the element at the specified position in this list with the specified element.

Parameters:
  `index` - index of element to replace
  `element` - element to be stored at the specified position
Returns:
  the element previously at the specified position
Throws:
  `ArrayIndexOutOfBoundsException` - if the index is out of range (`index &lt; 0 || index &gt;= size()`)

### add

public void add(int index, E element)
Inserts the specified element at the specified position in this list.

Parameters:
  `index` - index at which the specified element is to be inserted
  `element` - element to be inserted
Throws:
  `ArrayIndexOutOfBoundsException` - if the index is out of range (`index &lt; 0 || index &gt; size()`)

### remove

public E remove(int index)
Removes the element at the specified position in this list. Returns the element that was removed from the list

Parameters:
  `index` - the index of the element to removed
Returns:
  the element previously at the specified position
Throws:
  `ArrayIndexOutOfBoundsException` - if the index is out of range (`index &lt; 0 || index &gt;= size()`)

### clear

public void clear()
Removes all of the elements from this list. The list will be empty after this call returns (unless it throws an exception).

### removeRange

public void removeRange(int fromIndex, int toIndex)
Deletes the components at the specified range of indexes. The removal is inclusive, so specifying a range of (1,5) removes the component at index 1 and the component at index 5, as well as all components in between.

Parameters:
  `fromIndex` - the index of the lower end of the range
  `toIndex` - the index of the upper end of the range
Throws:
  `ArrayIndexOutOfBoundsException` - if the index was invalid
  `IllegalArgumentException` - if `fromIndex &gt; toIndex`
See Also:
  - `remove(int)`

### addAll

public void addAll(Collection<? extends E> c)
Adds all of the elements present in the collection to the list.

Parameters:
  `c` - the collection which contains the elements to add
Throws:
  `NullPointerException` - if `c` is null
Since:
  11

### addAll

public void addAll(int index, Collection<? extends E> c)
Adds all of the elements present in the collection, starting from the specified index.

Parameters:
  `index` - index at which to insert the first element from the specified collection
  `c` - the collection which contains the elements to add
Throws:
  `ArrayIndexOutOfBoundsException` - if `index` does not fall within the range of number of elements currently held
  `NullPointerException` - if `c` is null
Since:
  11