org.eclipse.emf.common.util
Class BasicEList

java.lang.Object
  extended byjava.util.AbstractCollection
      extended byjava.util.AbstractList
          extended byorg.eclipse.emf.common.util.BasicEList
All Implemented Interfaces:
Cloneable, Collection, EList, List, RandomAccess, Serializable
Direct Known Subclasses:
AbstractTreeIterator, BasicEList.FastCompare, BasicEList.UnmodifiableEList, BasicInternalEList, BasicNotifierImpl.EAdapterList, NotificationChainImpl, NotifyingListImpl, StringSegment, UniqueEList, XMLHandler.MyStack

public class BasicEList
extends AbstractList
implements EList, RandomAccess, Cloneable, Serializable

A highly extensible list implementation.

See Also:
Serialized Form

Nested Class Summary
protected static class BasicEList.BasicIndexOutOfBoundsException
          An IndexOutOfBoundsException that constructs a message from the argument data.
protected  class BasicEList.EIterator
          An extensible iterator implementation.
protected  class BasicEList.EListIterator
          An extensible list iterator implementation.
static class BasicEList.FastCompare
          A BasicEList that uses == instead of equals to compare members.
protected  class BasicEList.NonResolvingEIterator
          An extended read-only iterator that does not resolve objects.
protected  class BasicEList.NonResolvingEListIterator
          An extended read-only list iterator that does not resolve objects.
static class BasicEList.UnmodifiableEList
          An unmodifiable version of BasicEList.
 
Field Summary
protected  Object[] data
          The underlying data storage of the list.
protected  int size
          The size of the list.
 
Fields inherited from class java.util.AbstractList
modCount
 
Constructor Summary
  BasicEList()
          Creates an empty instance with no initial capacity.
  BasicEList(Collection collection)
          Creates an instance that is a copy of the collection.
  BasicEList(int initialCapacity)
          Creates an empty instance with the given capacity.
protected BasicEList(int size, Object[] data)
          Creates an initialized instance that directly uses the given arguments.
 
Method Summary
 void add(int index, Object object)
          Adds the object at the given index in the list.
 boolean add(Object object)
          Adds the object at the end of the list and returns whether the object was added; if uniqueness is required, duplicates will be ignored and false will be returned.
 boolean addAll(Collection collection)
          Adds each object of the collection to the end of the list.
 boolean addAll(int index, Collection collection)
          Adds each object of the collection at each successive index in the list and returns whether any objects were added.
 boolean addAllUnique(Collection collection)
          Adds each object of the collection to the end of the list; it does no uniqueness checking.
 boolean addAllUnique(int index, Collection collection)
          Adds each object of the collection at each successive index in the list and returns whether any objects were added; it does no ranging checking or uniqueness checking.
 boolean addAllUnique(int index, Object[] objects, int start, int end)
          Adds each object from start to end of the array at each successive index in the list and returns whether any objects were added; it does no ranging checking or uniqueness checking.
 boolean addAllUnique(Object[] objects, int start, int end)
          Adds each object from start to end of the array at the index of list and returns whether any objects were added; it does no ranging checking or uniqueness checking.
 void addUnique(int index, Object object)
          Adds the object at the given index in the list; it does no ranging checking or uniqueness checking.
 void addUnique(Object object)
          Adds the object at the end of the list; it does no uniqueness checking.
protected  Object assign(int index, Object object)
          Assigns the object into the data storage at the given index and returns the object that's been stored.
 Object basicGet(int index)
          Returns the object at the index without resolving it.
protected  Iterator basicIterator()
          Returns a read-only iterator that does not resolve objects.
protected  List basicList()
          Returns an unsafe list that provides a non-resolving view of the underlying data storage.
protected  ListIterator basicListIterator()
          Returns a read-only list iterator that does not resolve objects.
protected  ListIterator basicListIterator(int index)
          Returns a read-only list iterator advanced to the given index that does not resolve objects.
protected  boolean canContainNull()
          Returns whether null is a valid object for the list.
 void clear()
          Clears the list of all objects.
 Object clone()
          Returns a shallow copy of this list.
 boolean contains(Object object)
          Returns whether the list contains the object.
 boolean containsAll(Collection collection)
          Returns whether the list contains each object in the collection.
 Object[] data()
          Returns direct unsafe access to the underlying data storage.
protected  void didAdd(int index, Object newObject)
          Called to indicate that an object has been added to the data storage.
protected  void didChange()
          Called to indicate that the data storage has been changed.
protected  void didClear(int size, Object[] oldObjects)
          Called to indicate that the data storage has been cleared.
protected  void didMove(int index, Object movedObject, int oldIndex)
          Called to indicate that an object has been moved in the data storage.
protected  void didRemove(int index, Object oldObject)
          Called to indicate that an object has been removed from the data storage.
protected  void didSet(int index, Object newObject, Object oldObject)
          Called to indicate that the data storage has been set.
protected  boolean equalObjects(Object firstObject, Object secondObject)
          Returns whether two objects are equal using the appropriate comparison mechanism.
 boolean equals(Object object)
          Returns whether the object is a list with corresponding equal objects.
 Object get(int index)
          Returns the object at the index.
protected  Collection getDuplicates(Collection collection)
          Returns the collection of objects in the given collection that are also contained by this list.
protected  Collection getNonDuplicates(Collection collection)
          Returns the collection of objects in the given collection that are not also contained by this list.
 void grow(int minimumCapacity)
          Grows the capacity of the list to ensure that no additional growth is needed until the size exceeds the specified minimun capacity.
 int hashCode()
          Returns a hash code computed from each object's hash code.
 int indexOf(Object object)
          Returns the position of the first occurrence of the object in the list.
 boolean isEmpty()
          Returns whether the list has zero size.
protected  boolean isUnique()
          Returns whether objects are constrained to appear at most once in the list.
 Iterator iterator()
          Returns an iterator.
 int lastIndexOf(Object object)
          Returns the position of the last occurrence of the object in the list.
 ListIterator listIterator()
          Returns a list iterator.
 ListIterator listIterator(int index)
          Returns a list iterator advanced to the given index.
 Object move(int targetIndex, int sourceIndex)
          Moves the object at the source index of the list to the target index of the list and returns the moved object.
 void move(int index, Object object)
          Moves the object to the index of the list.
protected  Object[] newData(int capacity)
          Returns new allocated data storage.
 Object remove(int index)
          Removes the object at the index from the list and returns it.
 boolean remove(Object object)
          Removes the object from the list and returns whether the object was actually contained by the list.
 boolean removeAll(Collection collection)
          Removes each object of the collection from the list and returns whether any object was actually contained by the list.
protected  Object resolve(int index, Object object)
          Resolves the object at the index and returns the result.
 boolean retainAll(Collection collection)
          Removes from the list each object not contained by the collection and returns whether any object was actually removed.
 Object set(int index, Object object)
          Sets the object at the index and returns the old object at the index.
 void setData(int size, Object[] data)
          Updates directly and unsafely the underlying data storage.
 Object setUnique(int index, Object object)
          Sets the object at the index and returns the old object at the index; it does no ranging checking or uniqueness checking.
 void shrink()
          Shrinks the capacity of the list to the minimal requirements.
 int size()
          Returns the number of objects in the list.
 Object[] toArray()
          Returns an array containing all the objects in sequence.
 Object[] toArray(Object[] array)
          Returns an array containing all the objects in sequence.
 String toString()
          Returns a string of the form "[object1, object2]".
protected  boolean useEquals()
          Returns whether equals rather than == should be used to compare members.
protected  Object validate(int index, Object object)
          Validates a new content object and returns the validated object.
 
Methods inherited from class java.util.AbstractList
removeRange, subList
 
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait
 
Methods inherited from interface java.util.List
subList
 

Field Detail

size

protected int size
The size of the list.


data

protected transient Object[] data
The underlying data storage of the list.

Constructor Detail

BasicEList

public BasicEList()
Creates an empty instance with no initial capacity. The data storage will be null.


BasicEList

public BasicEList(int initialCapacity)
Creates an empty instance with the given capacity.

Parameters:
initialCapacity - the initial capacity of the list before it must grow.
Throws:
IllegalArgumentException - if the initialCapacity is negative.

BasicEList

public BasicEList(Collection collection)
Creates an instance that is a copy of the collection.

Parameters:
collection - the initial contents of the list.

BasicEList

protected BasicEList(int size,
                     Object[] data)
Creates an initialized instance that directly uses the given arguments.

Parameters:
size - the size of the list.
data - the underlying storage of the list.
Method Detail

newData

protected Object[] newData(int capacity)
Returns new allocated data storage. Clients may override this to create typed storage. The cost of type checking via a typed array is negligable.

Returns:
new data storage.

useEquals

protected boolean useEquals()
Returns whether equals rather than == should be used to compare members. The default is to return true but clients can optimize performance by returning false. The performance difference is highly significant.

Returns:
whether equals rather than == should be used.

equalObjects

protected boolean equalObjects(Object firstObject,
                               Object secondObject)
Returns whether two objects are equal using the appropriate comparison mechanism.

Returns:
whether two objects are equal.

canContainNull

protected boolean canContainNull()
Returns whether null is a valid object for the list. The default is to return true, but clients can override this to exclude null.

Returns:
whether null is a valid object for the list.

isUnique

protected boolean isUnique()
Returns whether objects are constrained to appear at most once in the list. The default is to return false, but clients can override this to ensure uniqueness of contents. The performance impact is signifcant: operations such as add are O(n) as a result requiring uniqueness.

Returns:
whether objects are constrained to appear at most once in the list.

validate

protected Object validate(int index,
                          Object object)
Validates a new content object and returns the validated object. This implementation checks for null, if necessary and returns the argument object. Clients may throw additional types of runtime exceptions in order to handle constraint violations.

Parameters:
index - the position of the new content.
object - the new content.
Returns:
the validated content.
Throws:
IllegalArgumentException - if a constraint prevents the object from being added.

assign

protected Object assign(int index,
                        Object object)
Assigns the object into the data storage at the given index and returns the object that's been stored. Clients can monitor access to the storage via this method.

Parameters:
index - the position of the new content.
object - the new content.
Returns:
the object that's been stored.

resolve

protected Object resolve(int index,
                         Object object)
Resolves the object at the index and returns the result. This implementation simply returns the object; clients can use this to transform objects as they are fetched.

Parameters:
index - the position of the content.
object - the content.
Returns:
the resolved object.

didSet

protected void didSet(int index,
                      Object newObject,
                      Object oldObject)
Called to indicate that the data storage has been set. This implementation does nothing; clients can use this to monitor settings to the data storage.

Parameters:
index - the position that was set.
newObject - the new object at the position.
oldObject - the old object at the position.

didAdd

protected void didAdd(int index,
                      Object newObject)
Called to indicate that an object has been added to the data storage. This implementation does nothing; clients can use this to monitor additions to the data storage.

Parameters:
index - the position object the new object.
newObject - the new object at the position.

didRemove

protected void didRemove(int index,
                         Object oldObject)
Called to indicate that an object has been removed from the data storage. This implementation does nothing; clients can use this to monitor removals from the data storage.

Parameters:
index - the position of the old object.
oldObject - the old object at the position.

didClear

protected void didClear(int size,
                        Object[] oldObjects)
Called to indicate that the data storage has been cleared. This implementation calls didRemove for each object; clients can use this to monitor clearing of the data storage.

Parameters:
size - the original size of the list.
oldObjects - the old data storage being discarded.
See Also:
didRemove(int, java.lang.Object)

didMove

protected void didMove(int index,
                       Object movedObject,
                       int oldIndex)
Called to indicate that an object has been moved in the data storage. This implementation does nothing; clients can use this to monitor movement in the data storage.

Parameters:
index - the position of the moved object.
movedObject - the moved object at the position.
oldIndex - the position the object was at before the move.

didChange

protected void didChange()
Called to indicate that the data storage has been changed. This implementation does nothing; clients can use this to monitor change in the data storage.


size

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

Specified by:
size in interface List
Returns:
the number of objects in the list.

isEmpty

public boolean isEmpty()
Returns whether the list has zero size.

Specified by:
isEmpty in interface List
Returns:
whether the list has zero size.

contains

public boolean contains(Object object)
Returns whether the list contains the object. This implementation uses either equals or "==" depending on useEquals.

Specified by:
contains in interface List
Parameters:
object - the object in question.
Returns:
whether the list contains the object.
See Also:
useEquals()

containsAll

public boolean containsAll(Collection collection)
Returns whether the list contains each object in the collection. This implementation delegates to contains, which may use either equals or "==" depending on useEquals.

Specified by:
containsAll in interface List
Parameters:
collection - the collection of objects in question.
Returns:
whether the list contains each object in the collection.
See Also:
contains(java.lang.Object), useEquals()

indexOf

public int indexOf(Object object)
Returns the position of the first occurrence of the object in the list. This implementation uses either equals or "==" depending on useEquals.

Specified by:
indexOf in interface List
Parameters:
object - the object in question.
Returns:
the position of the first occurrence of the object in the list.

lastIndexOf

public int lastIndexOf(Object object)
Returns the position of the last occurrence of the object in the list. This implementation uses either equals or "==" depending on useEquals.

Specified by:
lastIndexOf in interface List
Parameters:
object - the object in question.
Returns:
the position of the last occurrence of the object in the list.

toArray

public Object[] toArray()
Returns an array containing all the objects in sequence. Clients may override newData to create typed storage in this case.

Specified by:
toArray in interface List
Returns:
an array containing all the objects in sequence.
See Also:
newData(int)

toArray

public Object[] toArray(Object[] array)
Returns an array containing all the objects in sequence.

Specified by:
toArray in interface List
Parameters:
array - the array that will be filled and returned, if it's big enough; otherwise, a suitably large array of the same type will be allocated and used instead.
Returns:
an array containing all the objects in sequence.
See Also:
newData(int)

data

public Object[] data()
Returns direct unsafe access to the underlying data storage. Clients may not modify this and may not assume that the array remains valid as the list is modified.

Returns:
direct unsafe access to the underlying data storage.

setData

public void setData(int size,
                    Object[] data)
Updates directly and unsafely the underlying data storage. Clients must be aware that this subverts all callbacks and hence possibly the integrity of the list.


get

public Object get(int index)
Returns the object at the index. This implementation delegates to resolve so that clients may transform the fetched object.

Specified by:
get in interface List
Parameters:
index - the position in question.
Returns:
the object at the index.
Throws:
BasicEList.BasicIndexOutOfBoundsException - if the index isn't within the size range.
See Also:
resolve(int, java.lang.Object), basicGet(int)

basicGet

public Object basicGet(int index)
Returns the object at the index without resolving it.

Parameters:
index - the position in question.
Returns:
the object at the index.
Throws:
BasicEList.BasicIndexOutOfBoundsException - if the index isn't within the size range.
See Also:
resolve(int, java.lang.Object), get(int)

set

public Object set(int index,
                  Object object)
Sets the object at the index and returns the old object at the index. This implementation delegates to setUnique after range checking and after uniqueness checking.

Specified by:
set in interface List
Parameters:
index - the position in question.
object - the object to set.
Returns:
the old object at the index.
Throws:
BasicEList.BasicIndexOutOfBoundsException - if the index isn't within the size range.
IllegalArgumentException - if there is a constraint violation, e.g., non-uniqueness.
See Also:
setUnique(int, java.lang.Object)

setUnique

public Object setUnique(int index,
                        Object object)
Sets the object at the index and returns the old object at the index; it does no ranging checking or uniqueness checking. This implementation delegates to assign, didSet, and didChange.

Parameters:
index - the position in question.
object - the object to set.
Returns:
the old object at the index.
See Also:
set(int, java.lang.Object)

add

public boolean add(Object object)
Adds the object at the end of the list and returns whether the object was added; if uniqueness is required, duplicates will be ignored and false will be returned. This implementation delegates to addUnique(Object) after uniqueness checking.

Specified by:
add in interface List
Parameters:
object - the object to be added.
Returns:
whether the object was added.
See Also:
addUnique(Object)

addUnique

public void addUnique(Object object)
Adds the object at the end of the list; it does no uniqueness checking. This implementation delegates to assign, didAdd, and didChange. after uniqueness checking.

Parameters:
object - the object to be added.
See Also:
add(Object)

add

public void add(int index,
                Object object)
Adds the object at the given index in the list. If uniqueness is required, duplicates will be ignored. This implementation delegates to addUnique(int, Object) after uniqueness checking.

Specified by:
add in interface List
Parameters:
object - the object to be added.
Throws:
IllegalArgumentException - if uniqueness is required, and the object is a duplicate.
See Also:
addUnique(int, Object)

addUnique

public void addUnique(int index,
                      Object object)
Adds the object at the given index in the list; it does no ranging checking or uniqueness checking. This implementation delegates to assign, didAdd, and didChange.

Parameters:
object - the object to be added.
See Also:
add(int, Object)

addAll

public boolean addAll(Collection collection)
Adds each object of the collection to the end of the list. If uniqueness is required, duplicates will be removed from the collection, which could even result in an empty collection. This implementation delegates to addAllUnique(Collection) after uniqueness checking.

Specified by:
addAll in interface List
Parameters:
collection - the collection of objects to be added.
See Also:
addAllUnique(Collection)

addAllUnique

public boolean addAllUnique(Collection collection)
Adds each object of the collection to the end of the list; it does no uniqueness checking. This implementation delegates to assign, didAdd, and didChange.

Parameters:
collection - the collection of objects to be added.
See Also:
addAll(Collection)

addAll

public boolean addAll(int index,
                      Collection collection)
Adds each object of the collection at each successive index in the list and returns whether any objects were added. If uniqueness is required, duplicates will be removed from the collection, which could even result in an empty collection. This implementation delegates to addAllUnique(int, Collection) after uniqueness checking.

Specified by:
addAll in interface List
Parameters:
index - the index at which to add.
collection - the collection of objects to be added.
Returns:
whether any objects were added.
See Also:
addAllUnique(int, Collection)

addAllUnique

public boolean addAllUnique(int index,
                            Collection collection)
Adds each object of the collection at each successive index in the list and returns whether any objects were added; it does no ranging checking or uniqueness checking. This implementation delegates to assign, didAdd, and didChange.

Parameters:
index - the index at which to add.
collection - the collection of objects to be added.
Returns:
whether any objects were added.
See Also:
addAll(int, Collection)

addAllUnique

public boolean addAllUnique(Object[] objects,
                            int start,
                            int end)
Adds each object from start to end of the array at the index of list and returns whether any objects were added; it does no ranging checking or uniqueness checking. This implementation delegates to assign, didAdd, and didChange.

Parameters:
objects - the objects to be added.
start - the index of first object to be added.
end - the index past teh last object to be added.
Returns:
whether any objects were added.
See Also:
#addAllUnique(int Object[], int, int)

addAllUnique

public boolean addAllUnique(int index,
                            Object[] objects,
                            int start,
                            int end)
Adds each object from start to end of the array at each successive index in the list and returns whether any objects were added; it does no ranging checking or uniqueness checking. This implementation delegates to assign, didAdd, and didChange.

Parameters:
index - the index at which to add.
objects - the objects to be added.
start - the index of first object to be added.
end - the index past the last object to be added.
Returns:
whether any objects were added.
See Also:
addAllUnique(Object[], int, int)

remove

public boolean remove(Object object)
Removes the object from the list and returns whether the object was actually contained by the list. This implementation uses indexOf to find the object and delegates to remove(int) in the case that it finds the object.

Specified by:
remove in interface List
Parameters:
object - the object to be removed.
Returns:
whether the object was actually contained by the list.

removeAll

public boolean removeAll(Collection collection)
Removes each object of the collection from the list and returns whether any object was actually contained by the list.

Specified by:
removeAll in interface List
Parameters:
collection - the collection of objects to be removed.
Returns:
whether any object was actually contained by the list.

remove

public Object remove(int index)
Removes the object at the index from the list and returns it. This implementation delegates to didRemove and didChange.

Specified by:
remove in interface List
Parameters:
index - the position of the object to remove.
Returns:
the removed object.
Throws:
BasicEList.BasicIndexOutOfBoundsException - if the index isn't within the size range.

retainAll

public boolean retainAll(Collection collection)
Removes from the list each object not contained by the collection and returns whether any object was actually removed. This delegates to remove(int) in the case that it finds an object that isn't retained.

Specified by:
retainAll in interface List
Parameters:
collection - the collection of objects to be retained.
Returns:
whether any object was actually removed.

clear

public void clear()
Clears the list of all objects. This implementation discards the data storage without modifying it and delegates to didClear and didChange.

Specified by:
clear in interface List

move

public void move(int index,
                 Object object)
Moves the object to the index of the list. This implementation uses indexOf(java.lang.Object) of find the object and delegates to move(int, int).

Specified by:
move in interface EList
Parameters:
index - the new position for the object in the list.
object - the object to be moved.
Throws:
BasicEList.BasicIndexOutOfBoundsException - if the index isn't within the size range or the object isn't contained by the list.

move

public Object move(int targetIndex,
                   int sourceIndex)
Moves the object at the source index of the list to the target index of the list and returns the moved object. This implementation delegates to assign, didMove, and didChange.

Specified by:
move in interface EList
Parameters:
targetIndex - the new position for the object in the list.
sourceIndex - the old position of the object in the list.
Returns:
the moved object.
Throws:
BasicEList.BasicIndexOutOfBoundsException - if either index isn't within the size range.

shrink

public void shrink()
Shrinks the capacity of the list to the minimal requirements.

See Also:
grow(int)

grow

public void grow(int minimumCapacity)
Grows the capacity of the list to ensure that no additional growth is needed until the size exceeds the specified minimun capacity.

See Also:
shrink()

clone

public Object clone()
Returns a shallow copy of this list.

Returns:
a shallow copy of this list.

equals

public boolean equals(Object object)
Returns whether the object is a list with corresponding equal objects. This implementation uses either equals or "==" depending on useEquals.

Specified by:
equals in interface List
Returns:
whether the object is a list with corresponding equal objects.
See Also:
useEquals()

hashCode

public int hashCode()
Returns a hash code computed from each object's hash code.

Specified by:
hashCode in interface List
Returns:
a hash code.

toString

public String toString()
Returns a string of the form "[object1, object2]".

Returns:
a string of the form "[object1, object2]".

iterator

public Iterator iterator()
Returns an iterator. This implementation allocates a BasicEList.EIterator.

Specified by:
iterator in interface List
Returns:
an iterator.
See Also:
BasicEList.EIterator

basicIterator

protected Iterator basicIterator()
Returns a read-only iterator that does not resolve objects. This implementation allocates a BasicEList.NonResolvingEIterator.

Returns:
a read-only iterator that does not resolve objects.

listIterator

public ListIterator listIterator()
Returns a list iterator. This implementation allocates a BasicEList.EListIterator.

Specified by:
listIterator in interface List
Returns:
a list iterator.
See Also:
BasicEList.EListIterator

listIterator

public ListIterator listIterator(int index)
Returns a list iterator advanced to the given index. This implementation allocates a BasicEList.EListIterator.

Specified by:
listIterator in interface List
Parameters:
index - the starting index.
Returns:
a list iterator advanced to the index.
Throws:
BasicEList.BasicIndexOutOfBoundsException - if the index isn't within the size range.
See Also:
BasicEList.EListIterator

basicListIterator

protected ListIterator basicListIterator()
Returns a read-only list iterator that does not resolve objects. This implementation allocates a BasicEList.NonResolvingEListIterator.

Returns:
a read-only list iterator that does not resolve objects.

basicListIterator

protected ListIterator basicListIterator(int index)
Returns a read-only list iterator advanced to the given index that does not resolve objects. This implementation allocates a BasicEList.NonResolvingEListIterator.

Parameters:
index - the starting index.
Returns:
a read-only list iterator advanced to the index.
Throws:
BasicEList.BasicIndexOutOfBoundsException - if the index isn't within the size range.

basicList

protected List basicList()
Returns an unsafe list that provides a non-resolving view of the underlying data storage.

Returns:
an unsafe list that provides a non-resolving view of the underlying data storage.

getDuplicates

protected Collection getDuplicates(Collection collection)
Returns the collection of objects in the given collection that are also contained by this list.

Parameters:
collection - the other collection.
Returns:
the collection of objects in the given collection that are also contained by this list.

getNonDuplicates

protected Collection getNonDuplicates(Collection collection)
Returns the collection of objects in the given collection that are not also contained by this list.

Parameters:
collection - the other collection.
Returns:
the collection of objects in the given collection that are not also contained by this list.

Copyright 2001-2006 IBM Corporation and others.
All Rights Reserved.