jdk.util.concurrent.CopyOnWriteArrayList — clojure-interop/java.util.concurrent 1.0.5

A thread-safe variant of ArrayList in which all mutative operations (add, set, and so on) are implemented by making a fresh copy of the underlying array.

This is ordinarily too costly, but may be more efficient than alternatives when traversal operations vastly outnumber mutations, and is useful when you cannot or don't want to synchronize traversals, yet need to preclude interference among concurrent threads. The "snapshot" style iterator method uses a reference to the state of the array at the point that the iterator was created. This array never changes during the lifetime of the iterator, so interference is impossible and the iterator is guaranteed not to throw ConcurrentModificationException. The iterator will not reflect additions, removals, or changes to the list since the iterator was created. Element-changing operations on iterators themselves (remove, set, and add) are not supported. These methods throw UnsupportedOperationException.

All elements are permitted, including null.

Memory consistency effects: As with other concurrent collections, actions in a thread prior to placing an object into a CopyOnWriteArrayList happen-before actions subsequent to the access or removal of that element from the CopyOnWriteArrayList in another thread.

This class is a member of the

Java Collections Framework.

->copy-on-write-array-list clj

(->copy-on-write-array-list)

(->copy-on-write-array-list c)

Constructor.

Creates a list containing the elements of the specified collection, in the order they are returned by the collection's iterator.

c - the collection of initially held elements - java.util.Collection

throws: java.lang.NullPointerException - if the specified collection is null

add clj

(add this e)

(add this index element)

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

index - index at which the specified element is to be inserted - int element - element to be inserted - E

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

add-all clj

(add-all this c)

(add-all this index c)

Inserts all of the elements in the specified collection into this list, starting at the specified position. 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.

index - index at which to insert the first element from the specified collection - int c - collection containing elements to be added to this list - java.util.Collection

returns: true if this list changed as a result of the call - boolean

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

add-all-absent clj

(add-all-absent this c)

Appends all of the elements in the specified collection that are not already contained in this list, to the end of this list, in the order that they are returned by the specified collection's iterator.

c - collection containing elements to be added to this list - java.util.Collection

returns: the number of elements added - int

throws: java.lang.NullPointerException - if the specified collection is null

add-if-absent clj

(add-if-absent this e)

Appends the element, if not present.

e - element to be added to this list, if absent - E

returns: true if the element was added - boolean

clear clj

(clear this)

Removes all of the elements from this list. The list will be empty after this call returns.

clone clj

(clone this)

Returns a shallow copy of this list. (The elements themselves are not copied.)

returns: a clone of this list - java.lang.Object

contains clj

(contains this 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)).

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

returns: true if this list contains the specified element - boolean

contains-all clj

(contains-all this c)

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

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

returns: true if this list contains all of the elements of the specified collection - boolean

throws: java.lang.NullPointerException - if the specified collection is null

empty? clj

(empty? this)

Returns true if this list contains no elements.

returns: true if this list contains no elements - boolean

equals clj

(equals this o)

Compares the specified object with this list for equality. Returns true if the specified object is the same object as this object, or if it is also a List and the sequence of elements returned by an iterator over the specified list is the same as the sequence returned by an iterator over this list. The two sequences are considered to be the same if they have the same length and corresponding elements at the same position in the sequence are equal. Two elements e1 and e2 are considered equal if (e1==null ? e2==null : e1.equals(e2)).

o - the object to be compared for equality with this list - java.lang.Object

returns: true if the specified object is equal to this list - boolean

for-each clj

(for-each this action)

Description copied from interface: Iterable

action - The action to be performed for each element - java.util.function.Consumer

get clj

(get this index)

Returns the element at the specified position in this list.

index - index of the element to return - int

returns: the element at the specified position in this list - E

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

hash-code clj

(hash-code this)

Returns the hash code value for this list.

This implementation uses the definition in List.hashCode().

returns: the hash code value for this list - int

index-of clj

(index-of this o)

(index-of this e index)

Returns the index of the first occurrence of the specified element in this list, searching forwards from index, or returns -1 if the element is not found. More formally, returns the lowest index i such that (i >= index && (e==null ? get(i)==null : e.equals(get(i)))), or -1 if there is no such index.

e - element to search for - E index - index to start searching from - int

returns: the index of the first occurrence of the element in this list at position index or later in the list; -1 if the element is not found. - int

throws: java.lang.IndexOutOfBoundsException - if the specified index is negative

iterator clj

(iterator this)

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

The returned iterator provides a snapshot of the state of the list when the iterator was constructed. No synchronization is needed while traversing the iterator. The iterator does NOT support the remove method.

returns: an iterator over the elements in this list in proper sequence - java.util.Iterator<E>

last-index-of clj

(last-index-of this o)

(last-index-of this e index)

Returns the index of the last occurrence of the specified element in this list, searching backwards from index, or returns -1 if the element is not found. More formally, returns the highest index i such that (i <= index && (e==null ? get(i)==null : e.equals(get(i)))), or -1 if there is no such index.

e - element to search for - E index - index to start searching backwards from - int

returns: the index of the last occurrence of the element at position less than or equal to index in this list; -1 if the element is not found. - int

throws: java.lang.IndexOutOfBoundsException - if the specified index is greater than or equal to the current size of this list

list-iterator clj

(list-iterator this)

(list-iterator this index)

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

The returned iterator provides a snapshot of the state of the list when the iterator was constructed. No synchronization is needed while traversing the iterator. The iterator does NOT support the remove, set or add methods.

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

returns: a list iterator over the elements in this list (in proper sequence), starting at the specified position in the list - java.util.ListIterator<E>

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

remove clj

(remove this index)

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

index - the index of the element to be removed - int

returns: the element previously at the specified position - E

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

remove-all clj

(remove-all this c)

Removes from this list all of its elements that are contained in the specified collection. This is a particularly expensive operation in this class because of the need for an internal temporary array.

c - collection containing elements to be removed from this list - java.util.Collection

returns: true if this list changed as a result of the call - boolean

throws: java.lang.ClassCastException - if the class of an element of this list is incompatible with the specified collection (optional)

remove-if clj

(remove-if this filter)

Description copied from interface: Collection

filter - a predicate which returns true for elements to be removed - java.util.function.Predicate

returns: true if any elements were removed - boolean

replace-all clj

(replace-all this operator)

Description copied from interface: List

operator - the operator to apply to each element - java.util.function.UnaryOperator

retain-all clj

(retain-all this c)

Retains only the elements in this list that are contained in the specified collection. In other words, removes from this list all of its elements that are not contained in the specified collection.

c - collection containing elements to be retained in this list - java.util.Collection

returns: true if this list changed as a result of the call - boolean

throws: java.lang.ClassCastException - if the class of an element of this list is incompatible with the specified collection (optional)

set clj

(set this index element)

Replaces the element at the specified position in this list with the specified element.

index - index of the element to replace - int element - element to be stored at the specified position - E

returns: the element previously at the specified position - E

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

size clj

(size this)

Returns the number of elements in this list.

returns: the number of elements in this list - int

sort clj

(sort this c)

Description copied from interface: List

c - the Comparator used to compare list elements. A null value indicates that the elements' java.lang.natural ordering should be used - java.util.Comparator

spliterator clj

(spliterator this)

Returns a Spliterator over the elements in this list.

The Spliterator reports Spliterator.IMMUTABLE, Spliterator.ORDERED, Spliterator.SIZED, and Spliterator.SUBSIZED.

The spliterator provides a snapshot of the state of the list when the spliterator was constructed. No synchronization is needed while operating on the spliterator.

returns: a Spliterator over the elements in this list - java.util.Spliterator<E>

sub-list clj

(sub-list this from-index to-index)

Returns a view of the portion of this list between fromIndex, inclusive, and toIndex, exclusive. The returned list is backed by this list, so changes in the returned list are reflected in this list.

The semantics of the list returned by this method become undefined if the backing list (i.e., this list) is modified in any way other than via the returned list.

from-index - low endpoint (inclusive) of the subList - int to-index - high endpoint (exclusive) of the subList - int

returns: a view of the specified range within this list - java.util.List<E>

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

to-array clj

(to-array this)

(to-array this a)

Returns an array containing all of the elements in this list in proper sequence (from first to last element); the runtime type of the returned array is that of the specified array. If the list fits in the specified array, it is returned therein. Otherwise, a new array is allocated with the runtime type of the specified array and the size of this list.

If this list fits in the specified array with room to spare (i.e., the array has more elements than this list), the element in the array immediately following the end of the list is set to null. (This is useful in determining the length of this list only if the caller knows that this list does not contain any null elements.)

Like the toArray() method, this method acts as bridge between array-based and collection-based APIs. Further, this method allows precise control over the runtime type of the output array, and may, under certain circumstances, be used to save allocation costs.

Suppose x is a list known to contain only strings. The following code can be used to dump the list into a newly allocated array of String:

String[] y = x.toArray(new String[0]);

Note that toArray(new Object[0]) is identical in function to toArray().

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

returns: an array containing all the elements in this list - <T> T[]

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

to-string clj

(to-string this)

Returns a string representation of this list. The string representation consists of the string representations of the list'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).

returns: a string representation of this list - java.lang.String