com.levigo.util.base.glazedlists
Class AbstractEventList<E>

java.lang.Object
  com.levigo.util.base.glazedlists.AbstractEventList<E>

All Implemented Interfaces:

EventList<E>, Iterable<E>, Collection<E>, List<E>

Direct Known Subclasses:

BasicEventList, DebugList, TransformedList

public abstract class AbstractEventList<E>
extends Object
implements EventList<E>

A convenience class that implements common functionality for all EventLists.

If you are creating a custom EventList, consider extending the more feature-rich TransformedList.

Documentation Note: Javadoc tags have been copied from the List API because the javadoc tool does not inherit external descriptions.

Author:

Jesse Wilson

Field Summary

protected ListEventPublisher	publisher the publisher manages the distribution of changes
protected ReadWriteLock	readWriteLock the read/write lock provides mutual exclusion to access
protected ListEventAssembler<E>	updates the change event and notification system

Constructor Summary

protected	AbstractEventList() Create an AbstractEventList that sends events with the default ListEventPublisher.
protected	AbstractEventList(ListEventPublisher publisher) Creates an AbstractEventList that sends events using the specified ListEventPublisher.

Method Summary

boolean	add(E value) Appends the specified element to the end of this list (optional operation).
void	add(int index, E value) Inserts the specified element at the specified position in this list (optional operation).
boolean	addAll(Collection<? extends E> values) Appends all of the elements in the specified collection to the end of this list, in the order that they are returned by the specified collection's iterator (optional operation).
boolean	addAll(int index, Collection<? extends E> values) Inserts all of the elements in the specified collection into this list at the specified position (optional operation).
void	addListEventListener(ListEventListener<? super E> listChangeListener) Registers the specified listener to receive change updates for this list.
void	clear() Removes all of the elements from this list (optional operation).
boolean	contains(Object object) Returns true if this list contains the specified element.
boolean	containsAll(Collection<?> values) Returns true if this list contains all of the elements of the specified collection.
boolean	equals(Object object) Compares the specified object with this list for equality.
abstract E	get(int index) Returns the element at the specified position in this list.
ListEventPublisher	getPublisher() Get the publisher used to distribute ListEvents.
ReadWriteLock	getReadWriteLock() Gets the lock required to share this list between multiple threads.
int	hashCode() Returns the hash code value for this list.
int	indexOf(Object object) Returns the index in this list of the first occurrence of the specified element, or -1 if this list does not contain this element.
boolean	isEmpty() Returns true if this list contains no elements.
Iterator<E>	iterator() Returns an iterator over the elements in this list in proper sequence.
int	lastIndexOf(Object object) Returns the index in this list of the last occurrence of the specified element, or -1 if this list does not contain this element.
ListIterator<E>	listIterator() Returns a list iterator of the elements in this list (in proper sequence).
ListIterator<E>	listIterator(int index) Returns a list iterator of the elements in this list (in proper sequence), starting at the specified position in this list.
E	remove(int index) Removes the element at the specified position in this list (optional operation).
boolean	remove(Object toRemove) Removes the first occurrence in this list of the specified element (optional operation).
boolean	removeAll(Collection<?> values) Removes from this list all the elements that are contained in the specified collection (optional operation).
void	removeListEventListener(ListEventListener<? super E> listChangeListener) Removes the specified listener from receiving change updates for this list.
boolean	retainAll(Collection<?> values) Retains only the elements in this list that are contained in the specified collection (optional operation).
E	set(int index, E value) Replaces the element at the specified position in this list with the specified element (optional operation).
abstract int	size() Returns the number of elements in this list.
List<E>	subList(int fromIndex, int toIndex) Returns a view of the portion of this list between the specified fromIndex, inclusive, and toIndex, exclusive.
Object[]	toArray() Returns an array containing all of the elements in this list in proper sequence.
<T> T[]	toArray(T[] array) Returns an array containing all of the elements in this list in proper sequence; the runtime type of the returned array is that of the specified array.
String	toString() Returns a string representation of this collection.

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface com.levigo.util.base.glazedlists.EventList

dispose

Field Detail

updates

protected ListEventAssembler<E> updates

the change event and notification system

readWriteLock

protected ReadWriteLock readWriteLock

the read/write lock provides mutual exclusion to access

publisher

protected ListEventPublisher publisher

the publisher manages the distribution of changes

Constructor Detail

AbstractEventList

protected AbstractEventList(ListEventPublisher publisher)

Creates an AbstractEventList that sends events using the specified ListEventPublisher.

Parameters:

publisher - the channel for event distribution. If this is null, then a new ListEventPublisher will be created.

AbstractEventList

protected AbstractEventList()

Create an AbstractEventList that sends events with the default ListEventPublisher.

Method Detail

getPublisher

public ListEventPublisher getPublisher()

Get the publisher used to distribute ListEvents.

Specified by:

getPublisher in interface EventList<E>

getReadWriteLock

public ReadWriteLock getReadWriteLock()

Gets the lock required to share this list between multiple threads.

Specified by:

getReadWriteLock in interface EventList<E>

Returns:

a re-entrant ReadWriteLock that guarantees thread safe access to this list.

addListEventListener

public void addListEventListener(ListEventListener<? super E> listChangeListener)

Registers the specified listener to receive change updates for this list.

Specified by:

addListEventListener in interface EventList<E>

removeListEventListener

public void removeListEventListener(ListEventListener<? super E> listChangeListener)

Removes the specified listener from receiving change updates for this list.

Specified by:

removeListEventListener in interface EventList<E>

size

public abstract int size()

Returns the number of elements in this list. If this list contains more than Integer.MAX_VALUE elements, returns Integer.MAX_VALUE.

Specified by:

size in interface Collection<E>

Specified by:

size in interface List<E>

Returns:

the number of elements in this list.

isEmpty

public boolean isEmpty()

Returns true if this list contains no elements.

Specified by:

isEmpty in interface Collection<E>

Specified by:

isEmpty in interface List<E>

Returns:

true if this list contains no elements.

contains

public boolean contains(Object object)

Returns true if this list contains the specified element. More formally, returns true if and only if this list contains at least one element e such that (o==null ? e==null : o.equals(e)).

Specified by:

contains in interface Collection<E>

Specified by:

contains in interface List<E>

Parameters:

object - element whose presence in this list is to be tested.

Returns:

true if this list contains the specified element.

Throws:

ClassCastException - if the type of the specified element is incompatible with this list (optional).

NullPointerException - if the specified element is null and this list does not support null elements (optional).

iterator

public Iterator<E> iterator()

Returns an iterator over the elements in this list in proper sequence.

The returned Iterator will become inconsistent if the EventList that it views is modified. To overcome this problem, use listIterator(). When used concurrently, the returned Iterator requires locking via this list's ReadWriteLock.

Specified by:

iterator in interface Iterable<E>

Specified by:

iterator in interface Collection<E>

Specified by:

iterator in interface List<E>

Returns:

an iterator over the elements in this list in proper sequence.

toArray

public Object[] toArray()

Returns an array containing all of the elements in this list in proper sequence. Obeys the general contract of the Collection.toArray method.

Specified by:

toArray in interface Collection<E>

Specified by:

toArray in interface List<E>

Returns:

an array containing all of the elements in this list in proper sequence.

See Also:

Arrays.asList(T...)

toArray

public <T> T[] toArray(T[] array)

Returns an array containing all of the elements in this list in proper sequence; the runtime type of the returned array is that of the specified array. Obeys the general contract of the Collection.toArray(Object[]) method.

Specified by:

toArray in interface Collection<E>

Specified by:

toArray in interface List<E>

Parameters:

array - the array into which the elements of this list are to be stored, if it is big enough; otherwise, a new array of the same runtime type is allocated for this purpose.

Returns:

an array containing the elements of this list.

Throws:

ArrayStoreException - if the runtime type of the specified array is not a supertype of the runtime type of every element in this list.

NullPointerException - if the specified array is null.

add

public boolean add(E value)

Appends the specified element to the end of this list (optional operation).

Lists that support this operation may place limitations on what elements may be added to this list. In particular, some lists will refuse to add null elements, and others will impose restrictions on the type of elements that may be added. List classes should clearly specify in their documentation any restrictions on what elements may be added.

Specified by:

add in interface Collection<E>

Specified by:

add in interface List<E>

Parameters:

value - element to be appended to this list.

Returns:

true (as per the general contract of the Collection.add method).

Throws:

UnsupportedOperationException - if the add method is not supported by this list.

ClassCastException - if the class of the specified element prevents it from being added to this list.

NullPointerException - if the specified element is null and this list does not support null elements.

IllegalArgumentException - if some aspect of this element prevents it from being added to this list.

remove

public boolean remove(Object toRemove)

Removes the first occurrence in this list of the specified element (optional operation). If this list does not contain the element, it is unchanged. More formally, removes the element with the lowest index i such that (o==null ? get(i)==null : o.equals(get(i))) (if such an element exists).

Specified by:

remove in interface Collection<E>

Specified by:

remove in interface List<E>

Parameters:

toRemove - element to be removed from this list, if present.

Returns:

true if this list contained the specified element.

Throws:

ClassCastException - if the type of the specified element is incompatible with this list (optional).

NullPointerException - if the specified element is null and this list does not support null elements (optional).

UnsupportedOperationException - if the remove method is not supported by this list.

containsAll

public boolean containsAll(Collection<?> values)

Returns true if this list contains all of the elements of the specified collection.

Specified by:

containsAll in interface Collection<E>

Specified by:

containsAll in interface List<E>

Parameters:

values - collection to be checked for containment in this list.

Returns:

true if this list contains all of the elements of the specified collection.

Throws:

ClassCastException - if the types of one or more elements in the specified collection are incompatible with this list (optional).

NullPointerException - if the specified collection contains one or more null elements and this list does not support null elements (optional).

NullPointerException - if the specified collection is null.

See Also:

contains(Object)

addAll

public boolean addAll(Collection<? extends E> values)

Appends all of the elements in the specified collection to the end of this list, in the order that they are returned by the specified collection's iterator (optional operation). The behavior of this operation is unspecified if the specified collection is modified while the operation is in progress. (Note that this will occur if the specified collection is this list, and it's nonempty.)

Specified by:

addAll in interface Collection<E>

Specified by:

addAll in interface List<E>

Parameters:

values - collection whose elements are to be added to this list.

Returns:

true if this list changed as a result of the call.

Throws:

UnsupportedOperationException - if the addAll method is not supported by this list.

ClassCastException - if the class of an element in the specified collection prevents it from being added to this list.

NullPointerException - if the specified collection contains one or more null elements and this list does not support null elements, or if the specified collection is null.

IllegalArgumentException - if some aspect of an element in the specified collection prevents it from being added to this list.

See Also:

add(Object)

addAll

public boolean addAll(int index,
                      Collection<? extends E> values)

Inserts all of the elements in the specified collection into this list at the specified position (optional operation). Shifts the element currently at that position (if any) and any subsequent elements to the right (increases their indices). The new elements will appear in this list in the order that they are returned by the specified collection's iterator. The behavior of this operation is unspecified if the specified collection is modified while the operation is in progress. (Note that this will occur if the specified collection is this list, and it's nonempty.)

Specified by:

addAll in interface List<E>

Parameters:

index - index at which to insert first element from the specified collection.

values - elements to be inserted into this list.

Returns:

true if this list changed as a result of the call.

Throws:

UnsupportedOperationException - if the addAll method is not supported by this list.

ClassCastException - if the class of one of elements of the specified collection prevents it from being added to this list.

NullPointerException - if the specified collection contains one or more null elements and this list does not support null elements, or if the specified collection is null.

IllegalArgumentException - if some aspect of one of elements of the specified collection prevents it from being added to this list.

IndexOutOfBoundsException - if the index is out of range (index < 0 || index > size()).

removeAll

public boolean removeAll(Collection<?> values)

Removes from this list all the elements that are contained in the specified collection (optional operation).

Specified by:

removeAll in interface Collection<E>

Specified by:

removeAll in interface List<E>

Parameters:

values - collection that defines which elements will be removed from this list.

Returns:

true if this list changed as a result of the call.

Throws:

UnsupportedOperationException - if the removeAll method is not supported by this list.

ClassCastException - if the types of one or more elements in this list are incompatible with the specified collection (optional).

NullPointerException - if this list contains one or more null elements and the specified collection does not support null elements (optional).

NullPointerException - if the specified collection is null.

See Also:

remove(Object), contains(Object)

retainAll

public boolean retainAll(Collection<?> values)

Retains only the elements in this list that are contained in the specified collection (optional operation). In other words, removes from this list all the elements that are not contained in the specified collection.

Specified by:

retainAll in interface Collection<E>

Specified by:

retainAll in interface List<E>

Parameters:

values - collection that defines which elements this set will retain.

Returns:

true if this list changed as a result of the call.

Throws:

UnsupportedOperationException - if the retainAll method is not supported by this list.

ClassCastException - if the types of one or more elements in this list are incompatible with the specified collection (optional).

NullPointerException - if this list contains one or more null elements and the specified collection does not support null elements (optional).

NullPointerException - if the specified collection is null.

See Also:

remove(Object), contains(Object)

clear

public void clear()

Removes all of the elements from this list (optional operation). This list will be empty after this call returns (unless it throws an exception).

Specified by:

clear in interface Collection<E>

Specified by:

clear in interface List<E>

Throws:

UnsupportedOperationException - if the clear method is not supported by this list.

equals

public boolean equals(Object object)

Compares the specified object with this list for equality. Returns true if and only if the specified object is also a list, both lists have the same size, and all corresponding pairs of elements in the two lists are equal. (Two elements e1 and e2 are equal if (e1==null ? e2==null : e1.equals(e2)).) In other words, two lists are defined to be equal if they contain the same elements in the same order. This definition ensures that the equals method works properly across different implementations of the List interface.

Specified by:

equals in interface Collection<E>

Specified by:

equals in interface List<E>

Overrides:

equals in class Object

Parameters:

object - the object to be compared for equality with this list.

Returns:

true if the specified object is equal to this list.

hashCode

public int hashCode()

Returns the hash code value for this list. The hash code of a list is defined to be the result of the following calculation:

 hashCode = 1;
 Iterator i = list.iterator();
 while (i.hasNext()) {
   Object obj = i.next();
   hashCode = 31 * hashCode + (obj == null ? 0 : obj.hashCode());
 }
 

This ensures that list1.equals(list2) implies that list1.hashCode()==list2.hashCode() for any two lists, list1 and list2, as required by the general contract of Object.hashCode.

Specified by:

hashCode in interface Collection<E>

Specified by:

hashCode in interface List<E>

Overrides:

hashCode in class Object

Returns:

the hash code value for this list.

See Also:

Object.hashCode(), Object.equals(Object), equals(Object)

get

public abstract E get(int index)

Returns the element at the specified position in this list.

Specified by:

get in interface List<E>

Parameters:

index - index of element to return.

Returns:

the element at the specified position in this list.

Throws:

IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size()).

set

public E set(int index,
             E value)

Replaces the element at the specified position in this list with the specified element (optional operation).

Specified by:

set in interface List<E>

Parameters:

index - index of element to replace.

value - element to be stored at the specified position.

Returns:

the element previously at the specified position.

Throws:

UnsupportedOperationException - if the set method is not supported by this list.

ClassCastException - if the class of the specified element prevents it from being added to this list.

NullPointerException - if the specified element is null and this list does not support null elements.

IllegalArgumentException - if some aspect of the specified element prevents it from being added to this list.

IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size()).

add

public void add(int index,
                E value)

Inserts the specified element at the specified position in this list (optional operation). Shifts the element currently at that position (if any) and any subsequent elements to the right (adds one to their indices).

Specified by:

add in interface List<E>

Parameters:

index - index at which the specified element is to be inserted.

value - element to be inserted.

Throws:

UnsupportedOperationException - if the add method is not supported by this list.

ClassCastException - if the class of the specified element prevents it from being added to this list.

NullPointerException - if the specified element is null and this list does not support null elements.

IllegalArgumentException - if some aspect of the specified element prevents it from being added to this list.

IndexOutOfBoundsException - if the index is out of range (index < 0 || index > size()).

remove

public E remove(int index)

Removes the element at the specified position in this list (optional operation). Shifts any subsequent elements to the left (subtracts one from their indices). Returns the element that was removed from the list.

Specified by:

remove in interface List<E>

Parameters:

index - the index of the element to removed.

Returns:

the element previously at the specified position.

Throws:

UnsupportedOperationException - if the remove method is not supported by this list.

IndexOutOfBoundsException - if the index is out of range (index < 0 || index >= size()).

indexOf

public int indexOf(Object object)

Returns the index in this list of the first occurrence of the specified element, or -1 if this list does not contain this element. More formally, returns the lowest index i such that (o==null ? get(i)==null : o.equals(get(i))), or -1 if there is no such index.

Specified by:

indexOf in interface List<E>

Parameters:

object - element to search for.

Returns:

the index in this list of the first occurrence of the specified element, or -1 if this list does not contain this element.

Throws:

ClassCastException - if the type of the specified element is incompatible with this list (optional).

NullPointerException - if the specified element is null and this list does not support null elements (optional).

lastIndexOf

public int lastIndexOf(Object object)

Returns the index in this list of the last occurrence of the specified element, or -1 if this list does not contain this element. More formally, returns the highest index i such that (o==null ? get(i)==null : o.equals(get(i))), or -1 if there is no such index.

Specified by:

lastIndexOf in interface List<E>

Parameters:

object - element to search for.

Returns:

the index in this list of the last occurrence of the specified element, or -1 if this list does not contain this element.

Throws:

ClassCastException - if the type of the specified element is incompatible with this list (optional).

NullPointerException - if the specified element is null and this list does not support null elements (optional).

listIterator

public ListIterator<E> listIterator()

Returns a list iterator of the elements in this list (in proper sequence).

Unlike the ListIterator from a regular List, the EventList's ListIterator will remain consistent even if the EventList is changed externally. Note that when used concurrently, the returned ListIterator requires locking via this list's ReadWriteLock.

Specified by:

listIterator in interface List<E>

Returns:

a list iterator of the elements in this list (in proper sequence).

listIterator

public ListIterator<E> listIterator(int index)

Returns a list iterator of the elements in this list (in proper sequence), starting at the specified position in this list. The specified index indicates the first element that would be returned by an initial call to the next method. An initial call to the previous method would return the element with the specified index minus one.

Unlike the ListIterator from a regular List, the EventList's ListIterator will remain consistent even if the EventList is changed externally. Note that when used concurrently, the returned ListIterator requires locking via this list's ReadWriteLock.

Specified by:

listIterator in interface List<E>

Parameters:

index - index of first element to be returned from the list iterator (by a call to the next method).

Returns:

a list iterator of the elements in this list (in proper sequence), starting at the specified position in this list.

Throws:

IndexOutOfBoundsException - if the index is out of range (index < 0 || index > size()).

subList

public List<E> subList(int fromIndex,
                       int toIndex)

Returns a view of the portion of this list between the specified fromIndex, inclusive, and toIndex, exclusive. (If fromIndex and toIndex are equal, the returned list is empty.)

Unlike the standard List.subList() method, the List returned by this method will continue to be consistent even if the EventList it views is modified, structurally or otherwise. The returned List can always be safely cast to EventList. Note that when used concurrently, the returned List requires locking via this list's ReadWriteLock.

This method eliminates the need for explicit range operations (of the sort that commonly exist for arrays). Any operation that expects a list can be used as a range operation by passing a subList view instead of a whole list. For example, the following idiom removes a range of elements from a list:

 list.subList(from, to).clear();
 

Similar idioms may be constructed for indexOf and lastIndexOf, and all of the algorithms in the Collections class can be applied to a subList.

Specified by:

subList in interface List<E>

Parameters:

fromIndex - low endpoint (inclusive) of the subList.

toIndex - high endpoint (exclusive) of the subList.

Returns:

a view of the specified range within this list.

Throws:

IndexOutOfBoundsException - for an illegal endpoint index value (fromIndex < 0 || toIndex > size || fromIndex > toIndex).

toString

public String toString()

Returns a string representation of this collection. The string representation consists of a list of the collection's elements in the order they are returned by its iterator, enclosed in square brackets ("[]"). Adjacent elements are separated by the characters ", " (comma and space). Elements are converted to strings as by String.valueOf(Object).

This implementation creates an empty string buffer, appends a left square bracket, and iterates over the collection appending the string representation of each element in turn. After appending each element except the last, the string ", " is appended. Finally a right bracket is appended. A string is obtained from the string buffer, and returned.

Overrides:

toString in class Object

Returns:

a string representation of this collection.