jadex.commons.collection

Class WeakList<E>

java.lang.Object

jadex.commons.collection.WeakList<E>

All Implemented Interfaces:

java.io.Serializable, java.lang.Iterable<E>, java.util.Collection<E>, java.util.List<E>

public class WeakList<E>
extends java.lang.Object
implements java.util.List<E>, java.io.Serializable

A list with weak entries.

See Also:

Serialized Form

Field Summary

Fields

Modifier and Type	Field and Description
protected java.lang.ref.Reference<E>[]	array The list of elements.
protected java.lang.ref.ReferenceQueue	queue Reference queue for garbage-collected elements.
protected java.util.List<E>	serialized_list
protected int	size The number of elements.
protected int	state The state (to check for modifications).

Constructor Summary

Constructors

Constructor and Description
WeakList() Create a new list.

Method Summary

Modifier and Type	Method and Description
boolean	add(E o) Appends the specified element to the end of this list (optional operation).
void	add(int index, java.lang.Object o) Inserts the specified element at the specified position in this list (optional operation).
boolean	addAll(java.util.Collection collection) 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 collection) Inserts all of the elements in the specified collection into this list at the specified position (optional operation).
protected static void	checkForEmptySlots(java.util.List list) Check for empty slots in list.
void	clear() Removes all of the elements from this list (optional operation).
boolean	contains(java.lang.Object o) Returns
boolean	containsAll(java.util.Collection c) Returns
protected static java.lang.String[]	createTestvalues(java.lang.String teststring, int size) Create some string values for testing.
E	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
java.util.Iterator<E>	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<E>	listIterator() Returns a list iterator of the elements in this list (in proper sequence).
java.util.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.
static void	main(java.lang.String[] args) Main method for testing.
protected java.lang.Object	readResolve() Perform special handling on deserialization.
E	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).
java.lang.Object	set(int index, java.lang.Object o) 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<E>	subList(int fromIndex, int toIndex) Returns a view of the portion of this list between the specified
java.lang.Object[]	toArray() Returns an array containing all of the elements in this list in proper sequence.
java.lang.Object[]	toArray(java.lang.Object[] ret) 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.
java.lang.String	toString() Get the string representation.
protected java.lang.Object	writeReplace() Perform special handling on serialization.

Methods inherited from class java.lang.Object

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

Field Detail

array

protected transient java.lang.ref.Reference<E>[] array

The list of elements.

size

protected int size

The number of elements.

state

protected int state

The state (to check for modifications).

queue

protected transient java.lang.ref.ReferenceQueue queue

Reference queue for garbage-collected elements.

serialized_list

protected java.util.List<E> serialized_list

Constructor Detail

WeakList

public WeakList()

Create a new list.

Method Detail

size

public int size()

Returns the number of elements in this list. If this list contains more than

Specified by:

size in interface java.util.Collection<E>

Specified by:

size in interface java.util.List<E>

Returns:

the number of elements in this list.

isEmpty

public boolean isEmpty()

Returns

Specified by:

isEmpty in interface java.util.Collection<E>

Specified by:

isEmpty in interface java.util.List<E>

Returns:

contains

public boolean contains(java.lang.Object o)

Returns

Specified by:

contains in interface java.util.Collection<E>

Specified by:

contains in interface java.util.List<E>

Parameters:

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

Returns:

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.

iterator

public java.util.Iterator<E> iterator()

Returns an iterator over the elements in this list in proper sequence. Can handle garbage collection of elements, but fails fast in the presence of concurrent modifications.

Specified by:

iterator in interface java.lang.Iterable<E>

Specified by:

iterator in interface java.util.Collection<E>

Specified by:

iterator in interface java.util.List<E>

Returns:

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

toArray

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

Specified by:

toArray in interface java.util.Collection<E>

Specified by:

toArray in interface java.util.List<E>

Returns:

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

See Also:

Arrays.asList(Object[])

toArray

public java.lang.Object[] toArray(java.lang.Object[] ret)

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

Specified by:

toArray in interface java.util.Collection<E>

Specified by:

toArray in interface java.util.List<E>

Parameters:

ret - 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

add

public boolean add(E o)

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

Specified by:

add in interface java.util.Collection<E>

Specified by:

add in interface java.util.List<E>

Parameters:

o - element to be appended to this list.

Returns:

Throws:

java.lang.UnsupportedOperationException - if the

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 nul.

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

Specified by:

remove in interface java.util.Collection<E>

Specified by:

remove in interface java.util.List<E>

Parameters:

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

Returns:

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.

java.lang.UnsupportedOperationException - if the

containsAll

public boolean containsAll(java.util.Collection c)

Returns

Specified by:

containsAll in interface java.util.Collection<E>

Specified by:

containsAll in interface java.util.List<E>

Parameters:

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

Returns:

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).

java.lang.NullPointerException - if the specified collection is

See Also:

contains(Object)

addAll

public boolean addAll(java.util.Collection collection)

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<E>

Specified by:

addAll in interface java.util.List<E>

Parameters:

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

Returns:

Throws:

java.lang.UnsupportedOperationException - if the

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

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,
                      java.util.Collection collection)

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<E>

Parameters:

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

collection - elements to be inserted into this list.

Returns:

Throws:

java.lang.UnsupportedOperationException - if the

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

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(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<E>

Specified by:

removeAll in interface java.util.List<E>

Parameters:

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

Returns:

Throws:

java.lang.UnsupportedOperationException - if the

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).

java.lang.NullPointerException - if the specified collection is

See Also:

remove(Object), contains(Object)

retainAll

public boolean retainAll(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<E>

Specified by:

retainAll in interface java.util.List<E>

Parameters:

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

Returns:

Throws:

java.lang.UnsupportedOperationException - if the

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).

java.lang.NullPointerException - if the specified collection is

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<E>

Specified by:

clear in interface java.util.List<E>

get

public E get(int index)

Returns the element at the specified position in this list.

Specified by:

get in interface java.util.List<E>

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 java.lang.Object set(int index,
                            java.lang.Object o)

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

Specified by:

set in interface java.util.List<E>

Parameters:

index - index of element to replace.

o - element to be stored at the specified position.

Returns:

the element previously at the specified position.

Throws:

java.lang.UnsupportedOperationException - if the

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,
                java.lang.Object o)

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<E>

Parameters:

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

o - element to be inserted.

Throws:

java.lang.UnsupportedOperationException - if the

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 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 java.util.List<E>

Parameters:

index - the index of the element to removed.

Returns:

the element previously at the specified position.

Throws:

java.lang.UnsupportedOperationException - if the

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

Specified by:

indexOf in interface java.util.List<E>

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.

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

Specified by:

lastIndexOf in interface java.util.List<E>

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.

listIterator

public java.util.ListIterator<E> listIterator()

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

Specified by:

listIterator in interface java.util.List<E>

Returns:

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

listIterator

public java.util.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

Specified by:

listIterator in interface java.util.List<E>

Parameters:

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

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

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

Returns a view of the portion of this list between the specified

Specified by:

subList in interface java.util.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:

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

toString

public java.lang.String toString()

Get the string representation.

Overrides:

toString in class java.lang.Object

writeReplace

protected java.lang.Object writeReplace()
                                 throws java.io.ObjectStreamException

Perform special handling on serialization.

Throws:

java.io.ObjectStreamException

readResolve

protected java.lang.Object readResolve()
                                throws java.io.ObjectStreamException

Perform special handling on deserialization.

Throws:

java.io.ObjectStreamException

main

public static void main(java.lang.String[] args)

Main method for testing.

createTestvalues

protected static java.lang.String[] createTestvalues(java.lang.String teststring,
                                                     int size)

Create some string values for testing.

checkForEmptySlots

protected static void checkForEmptySlots(java.util.List list)

Check for empty slots in list.