de.caff.generics

Class RefWrapperList<V>

java.lang.Object

de.caff.generics.RefWrapperList<V>

All Implemented Interfaces:

java.lang.Iterable<V>, java.util.Collection<V>, java.util.List<V>

public class RefWrapperList<V>
extends java.lang.Object
implements java.util.List<V>

A list which holds its elements as references. The list will be automatically cleaned up when an iterator is constructed.

Author:

Rammi

Constructor Summary

Constructors

Modifier	Constructor and Description
	RefWrapperList(ReferenceCreator<? extends java.lang.ref.Reference<V>,V> creator) Default constructor.
	RefWrapperList(ReferenceCreator<? extends java.lang.ref.Reference<V>,V> creator, java.util.Collection<? extends V> c) Create a reference wrapper list from a collection.
protected	RefWrapperList(ReferenceCreator<? extends java.lang.ref.Reference<V>,V> creator, java.util.List<java.lang.ref.Reference<V>> wrappedList) Constructor.

Method Summary

Modifier and Type	Method and Description
void	add(int index, V element) Inserts the specified element at the specified position in this list (optional operation).
boolean	add(V o) Appends the specified element to the end of this list (optional operation).
boolean	addAll(java.util.Collection<? extends V> c) 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, java.util.Collection<? extends V> c) Inserts all of the elements in the specified collection into this list at the specified position (optional operation).
void	clear() Removes all of the elements from this list (optional operation).
boolean	contains(java.lang.Object o) Returns true if this list contains the specified element.
boolean	containsAll(java.util.Collection<?> c) Returns true if this list contains all of the elements of the specified collection.
static <W> RefWrapperList<W>	create(ReferenceCreator<? extends java.lang.ref.Reference<W>,W> creator, java.util.List<java.lang.ref.Reference<W>> baseList) Factory method which allows to define a given underlying list.
V	get(int index) Returns the element at the specified position in this list.
int	indexOf(java.lang.Object o) 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.
java.util.Iterator<V>	iterator() Returns an iterator over the elements in this list in proper sequence.
int	lastIndexOf(java.lang.Object o) Returns the index in this list of the last occurrence of the specified element, or -1 if this list does not contain this element.
java.util.ListIterator<V>	listIterator() Returns a list iterator of the elements in this list (in proper sequence).
java.util.ListIterator<V>	listIterator(int index) Returns a list iterator of the elements in this list (in proper sequence), starting at the specified position in this list.
V	remove(int index) Removes the element at the specified position in this list (optional operation).
boolean	remove(java.lang.Object o) Removes the first occurrence in this list of the specified element (optional operation).
boolean	removeAll(java.util.Collection<?> c) Removes from this list all the elements that are contained in the specified collection (optional operation).
boolean	retainAll(java.util.Collection<?> c) Retains only the elements in this list that are contained in the specified collection (optional operation).
V	set(int index, V element) Replaces the element at the specified position in this list with the specified element (optional operation).
int	size() Returns the number of elements in this list.
java.util.List<V>	subList(int fromIndex, int toIndex) Returns a view of the portion of this list between the specified fromIndex, inclusive, and toIndex, exclusive.
java.lang.Object[]	toArray() Returns an array containing all of the elements in this list in proper sequence.
<T> T[]	toArray(T[] a) 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.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.List

equals, hashCode, replaceAll, sort, spliterator

Methods inherited from interface java.util.Collection

parallelStream, removeIf, stream

Methods inherited from interface java.lang.Iterable

forEach

Constructor Detail

RefWrapperList

public RefWrapperList(@NotNull
                      ReferenceCreator<? extends java.lang.ref.Reference<V>,V> creator)

Default constructor. This will use a wrapped linked list.

Parameters:

creator - reference creator used to create the internally stored references

RefWrapperList

public RefWrapperList(@NotNull
                      ReferenceCreator<? extends java.lang.ref.Reference<V>,V> creator,
                      java.util.Collection<? extends V> c)

Create a reference wrapper list from a collection. This will use a wrapped linked list.

Parameters:

creator - reference creator used to create the internally stored references

c - collection the collection elements will be wrapped in the given reference type and added to this list

RefWrapperList

protected RefWrapperList(@NotNull
                         ReferenceCreator<? extends java.lang.ref.Reference<V>,V> creator,
                         @NotNull
                         java.util.List<java.lang.ref.Reference<V>> wrappedList)

Constructor. This allows to define a dedicated underlying list. As this wrapper has to have complete control of this list it should not be used elsewhere.

Parameters:

creator - reference creator used to create the internally stored references

wrappedList - wrapped list

Method Detail

size

public 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 java.util.Collection<V>

Specified by:

size in interface java.util.List<V>

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 java.util.Collection<V>

Specified by:

isEmpty in interface java.util.List<V>

Returns:

true if this list contains no elements.

contains

public boolean contains(java.lang.Object o)

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 java.util.Collection<V>

Specified by:

contains in interface java.util.List<V>

Parameters:

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

Returns:

true if this list contains the specified element.

Throws:

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

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

iterator

@NotNull
public java.util.Iterator<V> iterator()

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

Specified by:

iterator in interface java.lang.Iterable<V>

Specified by:

iterator in interface java.util.Collection<V>

Specified by:

iterator in interface java.util.List<V>

Returns:

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

toArray

@NotNull
public java.lang.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 java.util.Collection<V>

Specified by:

toArray in interface java.util.List<V>

Returns:

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

See Also:

Arrays.asList(Object[])

toArray

@NotNull
public <T> T[] toArray(@NotNull
                                T[] a)

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 java.util.Collection<V>

Specified by:

toArray in interface java.util.List<V>

Parameters:

a - 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:

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

java.lang.NullPointerException - if the specified array is null.

add

public boolean add(V o)

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 java.util.Collection<V>

Specified by:

add in interface java.util.List<V>

Parameters:

o - element to be appended to this list.

Returns:

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

Throws:

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

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

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

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

remove

public boolean remove(java.lang.Object o)

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 java.util.Collection<V>

Specified by:

remove in interface java.util.List<V>

Parameters:

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

Returns:

true if this list contained the specified element.

Throws:

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

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

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

containsAll

public boolean containsAll(@NotNull
                           java.util.Collection<?> c)

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

Specified by:

containsAll in interface java.util.Collection<V>

Specified by:

containsAll in interface java.util.List<V>

Parameters:

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

Returns:

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

Throws:

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

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

See Also:

contains(Object)

addAll

public boolean addAll(@NotNull
                      java.util.Collection<? extends V> c)

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 java.util.Collection<V>

Specified by:

addAll in interface java.util.List<V>

Parameters:

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

Returns:

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

Throws:

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

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

java.lang.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.

java.lang.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,
                      @NotNull
                      java.util.Collection<? extends V> c)

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 java.util.List<V>

Parameters:

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

c - elements to be inserted into this list.

Returns:

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

Throws:

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

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

java.lang.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.

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

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

removeAll

public boolean removeAll(@NotNull
                         java.util.Collection<?> c)

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

Specified by:

removeAll in interface java.util.Collection<V>

Specified by:

removeAll in interface java.util.List<V>

Parameters:

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

Returns:

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

Throws:

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

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

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

See Also:

remove(Object), contains(Object)

retainAll

public boolean retainAll(@NotNull
                         java.util.Collection<?> c)

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 java.util.Collection<V>

Specified by:

retainAll in interface java.util.List<V>

Parameters:

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

Returns:

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

Throws:

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

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

java.lang.NullPointerException - if this list contains one or more null elements and the specified collection does not support null elements (optional); or 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 java.util.Collection<V>

Specified by:

clear in interface java.util.List<V>

Throws:

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

get

public V get(int index)

Returns the element at the specified position in this list.

Specified by:

get in interface java.util.List<V>

Parameters:

index - index of element to return.

Returns:

the element at the specified position in this list.

Throws:

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

set

public V set(int index,
             V element)

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

Specified by:

set in interface java.util.List<V>

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:

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

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

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

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

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

add

public void add(int index,
                V element)

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 java.util.List<V>

Parameters:

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

element - element to be inserted.

Throws:

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

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

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

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

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

remove

public V 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 java.util.List<V>

Parameters:

index - the index of the element to removed.

Returns:

the element previously at the specified position.

Throws:

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

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

indexOf

public int indexOf(java.lang.Object o)

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 java.util.List<V>

Parameters:

o - 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:

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

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

lastIndexOf

public int lastIndexOf(java.lang.Object o)

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 java.util.List<V>

Parameters:

o - 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:

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

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

listIterator

@NotNull
public java.util.ListIterator<V> listIterator()

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

Specified by:

listIterator in interface java.util.List<V>

Returns:

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

listIterator

@NotNull
public java.util.ListIterator<V> 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.

Specified by:

listIterator in interface java.util.List<V>

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:

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

subList

@NotNull
public java.util.List<V> 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.) The returned list is backed by this list, so non-structural changes in the returned list are reflected in this list, and vice-versa. The returned list supports all of the optional list operations supported by this list.

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.

The semantics of the list returned by this method become undefined if the backing list (i.e., this list) is structurally modified in any way other than via the returned list. (Structural modifications are those that change the size of this list, or otherwise perturb it in such a fashion that iterations in progress may yield incorrect results.)

Specified by:

subList in interface java.util.List<V>

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:

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

create

public static <W> RefWrapperList<W> create(@NotNull
                                           ReferenceCreator<? extends java.lang.ref.Reference<W>,W> creator,
                                           @NotNull
                                           java.util.List<java.lang.ref.Reference<W>> baseList)

Factory method which allows to define a given underlying list. This allows to define a dedicated underlying list. As this wrapper has to have complete control of this list it should not be used elsewhere. The recommended way of invoking this constructor is (e.g. for ArrayList)

   refWrapperList =
      RefWrapperList.create(ReferenceUtil.getSoftReferenceCreator
                            new ArrayList<Reference<XY>>());
 }
 

Type Parameters:

W - value type

Parameters:

creator - reference creator

baseList - basic list

Returns:

reference wrapper list based on baseList