MutableObjectList

Artifact: androidx.collection:collection

Added in 1.4.0

Kotlin |Java

public final class MutableObjectList<E extends Object> extends ObjectList

java.lang.Object
↳	androidx.collection.ObjectList
	↳	androidx.collection.MutableObjectList

MutableObjectList is a MutableList-like collection for reference types. It is optimized for fast access, avoiding virtual and interface method access. Methods avoid allocation whenever possible. For example forEach does not need allocate an Iterator.

This implementation is not thread-safe: if multiple threads access this container concurrently, and one or more threads modify the structure of the list (insertion or removal for instance), the calling code must provide the appropriate synchronization. It is also not safe to mutate during reentrancy -- in the middle of a forEach, for example. However, concurrent reads are safe.

Note List access is available through asList when developers need access to the common API.

Note MutableList access is available through asMutableList when developers need access to the common API.

It is best to use this for all internal implementations where a list of reference types is needed. Use MutableList in public API to take advantage of the commonly-used interface. It is common to use MutableObjectList internally and use asMutableList or asList to get a MutableList or List interface for interacting with public APIs.

MutableLongList

See also
`ObjectList`
`MutableFloatList`
`MutableIntList`

Summary

Public constructors
`<E extends Object> MutableObjectList(int initialCapacity)`

Public methods
`final boolean`	`add(@NonNull E element)` Adds `element` to the `MutableObjectList` and returns `true`.
`final void`	`add(@IntRange(from = 0) int index, @NonNull E element)` Adds `element` to the `MutableObjectList` at the given `index`, shifting over any elements at `index` and after, if any.
`final boolean`	`addAll(@NonNull E[] elements)` Adds all `elements` to the end of the `MutableObjectList` and returns `true` if the `MutableObjectList` was changed or `false` if `elements` was empty.
`final boolean`	`addAll(@NonNull Iterable<@NonNull E> elements)` Adds all `elements` to the end of the `MutableObjectList` and returns `true` if the `MutableObjectList` was changed or `false` if `elements` was empty.
`final boolean`	`addAll(@NonNull List<@NonNull E> elements)` Adds all `elements` to the end of the `MutableObjectList` and returns `true` if the `MutableObjectList` was changed or `false` if `elements` was empty.
`final boolean`	`addAll(@NonNull ObjectList<@NonNull E> elements)` Adds all `elements` to the end of the `MutableObjectList` and returns `true` if the `MutableObjectList` was changed or `false` if `elements` was empty.
`final boolean`	`addAll(@NonNull ScatterSet<@NonNull E> elements)` Adds all `elements` to the end of the `MutableObjectList` and returns `true` if the `MutableObjectList` was changed or `false` if `elements` was empty.
`final boolean`	`addAll(@NonNull Sequence<@NonNull E> elements)` Adds all `elements` to the end of the `MutableObjectList` and returns `true` if the `MutableObjectList` was changed or `false` if `elements` was empty.
`final boolean`	`addAll(@IntRange(from = 0) int index, @NonNull E[] elements)` Adds all `elements` to the `MutableObjectList` at the given `index`, shifting over any elements at `index` and after, if any.
`final boolean`	`addAll(@IntRange(from = 0) int index, @NonNull Collection<@NonNull E> elements)` Adds all `elements` to the `MutableObjectList` at the given `index`, shifting over any elements at `index` and after, if any.
`final boolean`	`addAll(@IntRange(from = 0) int index, @NonNull ObjectList<@NonNull E> elements)` Adds all `elements` to the `MutableObjectList` at the given `index`, shifting over any elements at `index` and after, if any.
`@NonNull List<@NonNull E>`	`asList()` Returns a `List` view into the `ObjectList`.
`final @NonNull List<@NonNull E>`	`asMutableList()` Returns a `MutableList` view into the `MutableObjectList`.
`final void`	`clear()` Removes all elements in the `MutableObjectList`.
`final void`	`ensureCapacity(int capacity)` Ensures that there is enough space to store `capacity` elements in the `MutableObjectList`.
`final int`	`getCapacity()` Returns the total number of elements that can be held before the `MutableObjectList` must grow.
`final void`	`minusAssign(@NonNull E element)` `remove` from the `MutableObjectList`
`final void`	`minusAssign(@NonNull E[] elements)` Removes all `elements` from the `MutableObjectList`.
`final void`	`minusAssign(@NonNull Iterable<@NonNull E> elements)` Removes all `elements` from the `MutableObjectList`.
`final void`	`minusAssign(@NonNull List<@NonNull E> elements)` Removes all `elements` from the `MutableObjectList`.
`final void`	`minusAssign(@NonNull ObjectList<@NonNull E> elements)` Removes all `elements` from the `MutableObjectList`.
`final void`	`minusAssign(@NonNull ScatterSet<@NonNull E> elements)` Removes all `elements` from the `MutableObjectList`.
`final void`	`minusAssign(@NonNull Sequence<@NonNull E> elements)` Removes all `elements` from the `MutableObjectList`.
`final void`	`plusAssign(@NonNull E element)` `add` to the `MutableObjectList`.
`final void`	`plusAssign(@NonNull E[] elements)` Adds all `elements` to the end of the `MutableObjectList`.
`final void`	`plusAssign(@NonNull Iterable<@NonNull E> elements)` Adds all `elements` to the end of the `MutableObjectList`.
`final void`	`plusAssign(@NonNull List<@NonNull E> elements)` Adds all `elements` to the end of the `MutableObjectList`.
`final void`	`plusAssign(@NonNull ObjectList<@NonNull E> elements)` Adds all `elements` to the end of the `MutableObjectList`.
`final void`	`plusAssign(@NonNull ScatterSet<@NonNull E> elements)` Adds all `elements` to the end of the `MutableObjectList`.
`final void`	`plusAssign(@NonNull Sequence<@NonNull E> elements)` Adds all `elements` to the end of the `MutableObjectList`.
`final boolean`	`remove(@NonNull E element)` Removes `element` from the `MutableObjectList`.
`final boolean`	`removeAll(@NonNull E[] elements)` Removes all `elements` from the `MutableObjectList` and returns `true` if anything was removed.
`final boolean`	`removeAll(@NonNull Iterable<@NonNull E> elements)` Removes all `elements` from the `MutableObjectList` and returns `true` if anything was removed.
`final boolean`	`removeAll(@NonNull List<@NonNull E> elements)` Removes all `elements` from the `MutableObjectList` and returns `true` if anything was removed.
`final boolean`	`removeAll(@NonNull ObjectList<@NonNull E> elements)` Removes all `elements` from the `MutableObjectList` and returns `true` if anything was removed.
`final boolean`	`removeAll(@NonNull ScatterSet<@NonNull E> elements)` Removes all `elements` from the `MutableObjectList` and returns `true` if anything was removed.
`final boolean`	`removeAll(@NonNull Sequence<@NonNull E> elements)` Removes all `elements` from the `MutableObjectList` and returns `true` if anything was removed.
`final @NonNull E`	`removeAt(@IntRange(from = 0) int index)` Removes the element at the given `index` and returns it.
`final void`	`removeIf(@NonNull Function1<@NonNull element, @NonNull Boolean> predicate)` Removes all elements in this list for which `predicate` returns `true`.
`final void`	`removeRange(@IntRange(from = 0) int start, @IntRange(from = 0) int end)` Removes elements from index `start` (inclusive) to `end` (exclusive).
`final boolean`	`retainAll(@NonNull E[] elements)` Keeps only `elements` in the `MutableObjectList` and removes all other values.
`final boolean`	`retainAll(@NonNull Collection<@NonNull E> elements)` Keeps only `elements` in the `MutableObjectList` and removes all other values.
`final boolean`	`retainAll(@NonNull Iterable<@NonNull E> elements)` Keeps only `elements` in the `MutableObjectList` and removes all other values.
`final boolean`	`retainAll(@NonNull ObjectList<@NonNull E> elements)` Keeps only `elements` in the `MutableObjectList` and removes all other values.
`final boolean`	`retainAll(@NonNull Sequence<@NonNull E> elements)` Keeps only `elements` in the `MutableObjectList` and removes all other values.
`final @NonNull E`	`set(@IntRange(from = 0) int index, @NonNull E element)` Sets the value at `index` to `element`.
`final void`	`trim(int minCapacity)` Reduces the internal storage.

Inherited methods

From androidx.collection.ObjectList

`final boolean`	`any()` Returns `true` if there's at least one element in the collection.
`final boolean`	`any(@NonNull Function1<@NonNull element, @NonNull Boolean> predicate)` Returns `true` if any of the elements give a `true` return value for `predicate`.
`final boolean`	`contains(@NonNull E element)` Returns `true` if the `ObjectList` contains `element` or `false` otherwise.
`final boolean`	`containsAll(@NonNull E[] elements)` Returns `true` if the `ObjectList` contains all elements in `elements` or `false` if one or more are missing.
`final boolean`	`containsAll(@NonNull Iterable<@NonNull E> elements)` Returns `true` if the `ObjectList` contains all elements in `elements` or `false` if one or more are missing.
`final boolean`	`containsAll(@NonNull List<@NonNull E> elements)` Returns `true` if the `ObjectList` contains all elements in `elements` or `false` if one or more are missing.
`final boolean`	`containsAll(@NonNull ObjectList<@NonNull E> elements)` Returns `true` if the `ObjectList` contains all elements in `elements` or `false` if one or more are missing.
`final int`	`count()` Returns the number of elements in this list.
`final int`	`count(@NonNull Function1<@NonNull element, @NonNull Boolean> predicate)` Counts the number of elements matching `predicate`.
`final @NonNull E`	`elementAt(@IntRange(from = 0) int index)` Returns the element at the given `index` or throws `IndexOutOfBoundsException` if the `index` is out of bounds of this collection.
`final @NonNull E`	`elementAtOrElse( @IntRange(from = 0) int index, @NonNull Function1<@NonNull Integer, @NonNull E> defaultValue )` Returns the element at the given `index` or `defaultValue` if `index` is out of bounds of the collection.
`boolean`	`equals(Object other)` Returns `true` if `other` is a `ObjectList` and the contents of this and `other` are the same.
`final @NonNull E`	`first()` Returns the first element in the `ObjectList` or throws a `NoSuchElementException` if it `isEmpty`.
`final @NonNull E`	`first(@NonNull Function1<@NonNull element, @NonNull Boolean> predicate)` Returns the first element in the `ObjectList` for which `predicate` returns `true` or throws `NoSuchElementException` if nothing matches.
`final E`	`firstOrNull()` Returns the first element in the `ObjectList` or `null` if it `isEmpty`.
`final E`	`firstOrNull( @NonNull Function1<@NonNull element, @NonNull Boolean> predicate )` Returns the first element in the `ObjectList` for which `predicate` returns `true` or `null` if nothing matches.
`final @NonNull R`	`<R extends Object> fold( @NonNull R initial, @NonNull Function2<@NonNull acc, @NonNull element, @NonNull R> operation )` Accumulates values, starting with `initial`, and applying `operation` to each element in the `ObjectList` in order.
`final @NonNull R`	`<R extends Object> foldIndexed( @NonNull R initial, @NonNull Function3<@NonNull Integer, @NonNull acc, @NonNull element, @NonNull R> operation )` Accumulates values, starting with `initial`, and applying `operation` to each element in the `ObjectList` in order.
`final @NonNull R`	`<R extends Object> foldRight( @NonNull R initial, @NonNull Function2<@NonNull element, @NonNull acc, @NonNull R> operation )` Accumulates values, starting with `initial`, and applying `operation` to each element in the `ObjectList` in reverse order.
`final @NonNull R`	`<R extends Object> foldRightIndexed( @NonNull R initial, @NonNull Function3<@NonNull Integer, @NonNull element, @NonNull acc, @NonNull R> operation )` Accumulates values, starting with `initial`, and applying `operation` to each element in the `ObjectList` in reverse order.
`final void`	`forEach(@NonNull Function1<@NonNull element, Unit> block)` Calls `block` for each element in the `ObjectList`, in order.
`final void`	`forEachIndexed( @NonNull Function2<@NonNull Integer, @NonNull element, Unit> block )` Calls `block` for each element in the `ObjectList` along with its index, in order.
`final void`	`forEachReversed(@NonNull Function1<@NonNull element, Unit> block)` Calls `block` for each element in the `ObjectList` in reverse order.
`final void`	`forEachReversedIndexed( @NonNull Function2<@NonNull Integer, @NonNull element, Unit> block )` Calls `block` for each element in the `ObjectList` along with its index, in reverse order.
`final @NonNull E`	`get(@IntRange(from = 0) int index)` Returns the element at the given `index` or throws `IndexOutOfBoundsException` if the `index` is out of bounds of this collection.
`final @NonNull IntRange`	`getIndices()` Returns an `IntRange` of the valid indices for this `ObjectList`.
`final @IntRange(from = -1) int`	`getLastIndex()` Returns the last valid index in the `ObjectList`.
`final @IntRange(from = 0) int`	`getSize()` The number of elements in the `ObjectList`.
`int`	`hashCode()` Returns a hash code based on the contents of the `ObjectList`.
`final int`	`indexOf(@NonNull E element)` Returns the index of `element` in the `ObjectList` or `-1` if `element` is not there.
`final int`	`indexOfFirst( @NonNull Function1<@NonNull element, @NonNull Boolean> predicate )` Returns the index if the first element in the `ObjectList` for which `predicate` returns `true` or -1 if there was no element for which predicate returned `true`.
`final int`	`indexOfLast( @NonNull Function1<@NonNull element, @NonNull Boolean> predicate )` Returns the index if the last element in the `ObjectList` for which `predicate` returns `true` or -1 if there was no element for which predicate returned `true`.
`final boolean`	`isEmpty()` Returns `true` if the `ObjectList` has no elements in it or `false` otherwise.
`final boolean`	`isNotEmpty()` Returns `true` if there are elements in the `ObjectList` or `false` if it is empty.
`final @NonNull String`	`joinToString( @NonNull CharSequence separator, @NonNull CharSequence prefix, @NonNull CharSequence postfix, int limit, @NonNull CharSequence truncated, Function1<@NonNull E, @NonNull CharSequence> transform )` Creates a String from the elements separated by `separator` and using `prefix` before and `postfix` after, if supplied.
`final @NonNull E`	`last()` Returns the last element in the `ObjectList` or throws a `NoSuchElementException` if it `isEmpty`.
`final @NonNull E`	`last(@NonNull Function1<@NonNull element, @NonNull Boolean> predicate)` Returns the last element in the `ObjectList` for which `predicate` returns `true` or throws `NoSuchElementException` if nothing matches.
`final int`	`lastIndexOf(@NonNull E element)` Returns the index of the last element in the `ObjectList` that is the same as `element` or `-1` if no elements match.
`final E`	`lastOrNull()` Returns the last element in the `ObjectList` or `null` if it `isEmpty`.
`final E`	`lastOrNull(@NonNull Function1<@NonNull element, @NonNull Boolean> predicate)` Returns the last element in the `ObjectList` for which `predicate` returns `true` or `null` if nothing matches.
`final boolean`	`none()` Returns `true` if the collection has no elements in it.
`final boolean`	`reversedAny( @NonNull Function1<@NonNull element, @NonNull Boolean> predicate )` Returns `true` if any of the elements give a `true` return value for `predicate` while iterating in the reverse order.
`@NonNull String`	`toString()` Returns a String representation of the list, surrounded by "[]" and each element separated by ", ".

Public constructors

MutableObjectList

public <E extends Object> MutableObjectList(int initialCapacity)

Public methods

add

Added in 1.4.0

public final boolean add(@NonNull E element)

Adds element to the MutableObjectList and returns true.

add

Added in 1.4.0

public final void add(@IntRange(from = 0) int index, @NonNull E element)

Adds element to the MutableObjectList at the given index, shifting over any elements at index and after, if any.

Throws
`kotlin.IndexOutOfBoundsException`	if `index` isn't between 0 and `size`, inclusive

addAll

Added in 1.4.0

public final boolean addAll(@NonNull E[] elements)

Adds all elements to the end of the MutableObjectList and returns true if the MutableObjectList was changed or false if elements was empty.

addAll

public final boolean addAll(@NonNull Iterable<@NonNull E> elements)

Adds all elements to the end of the MutableObjectList and returns true if the MutableObjectList was changed or false if elements was empty.

addAll

public final boolean addAll(@NonNull List<@NonNull E> elements)

Adds all elements to the end of the MutableObjectList and returns true if the MutableObjectList was changed or false if elements was empty.

addAll

Added in 1.4.0

public final boolean addAll(@NonNull ObjectList<@NonNull E> elements)

Adds all elements to the end of the MutableObjectList and returns true if the MutableObjectList was changed or false if elements was empty.

addAll

Added in 1.4.0

public final boolean addAll(@NonNull ScatterSet<@NonNull E> elements)

Adds all elements to the end of the MutableObjectList and returns true if the MutableObjectList was changed or false if elements was empty.

addAll

public final boolean addAll(@NonNull Sequence<@NonNull E> elements)

Adds all elements to the end of the MutableObjectList and returns true if the MutableObjectList was changed or false if elements was empty.

addAll

Added in 1.4.0

public final boolean addAll(@IntRange(from = 0) int index, @NonNull E[] elements)

Adds all elements to the MutableObjectList at the given index, shifting over any elements at index and after, if any.

Returns
`boolean`	`true` if the `MutableObjectList` was changed or `false` if `elements` was empty

Throws
`kotlin.IndexOutOfBoundsException`	if `index` isn't between 0 and `size`, inclusive.

addAll

public final boolean addAll(@IntRange(from = 0) int index, @NonNull Collection<@NonNull E> elements)

Adds all elements to the MutableObjectList at the given index, shifting over any elements at index and after, if any.

Returns
`boolean`	`true` if the `MutableObjectList` was changed or `false` if `elements` was empty

Throws
`kotlin.IndexOutOfBoundsException`	if `index` isn't between 0 and `size`, inclusive.

addAll

Added in 1.4.0

public final boolean addAll(@IntRange(from = 0) int index, @NonNull ObjectList<@NonNull E> elements)

Adds all elements to the MutableObjectList at the given index, shifting over any elements at index and after, if any.

Returns
`boolean`	`true` if the `MutableObjectList` was changed or `false` if `elements` was empty

Throws
`kotlin.IndexOutOfBoundsException`	if `index` isn't between 0 and `size`, inclusive

asList

Added in 1.5.0-beta01

public @NonNull List<@NonNull E> asList()

Returns a List view into the ObjectList. All access to the collection will be less efficient and abides by the allocation requirements of the List. For example, List.forEach will allocate an iterator. All access will go through the more expensive interface calls. Critical performance areas should use the ObjectList API rather than List API, when possible.

asMutableList

Added in 1.4.0

public final @NonNull List<@NonNull E> asMutableList()

Returns a MutableList view into the MutableObjectList. All access to the collection will be less efficient and abides by the allocation requirements of the MutableList. For example, MutableList.forEach will allocate an iterator. All access will go through the more expensive interface calls. Critical performance areas should use the MutableObjectList API rather than MutableList API, when possible.

clear

Added in 1.4.0

public final void clear()

Removes all elements in the MutableObjectList. The storage isn't released.

See also
`trim`

ensureCapacity

Added in 1.4.0

public final void ensureCapacity(int capacity)

Ensures that there is enough space to store capacity elements in the MutableObjectList.

See also
`trim`

getCapacity

Added in 1.4.0

public final int getCapacity()

Returns the total number of elements that can be held before the MutableObjectList must grow.

See also
`ensureCapacity`

minusAssign

Added in 1.4.0

public final void minusAssign(@NonNull E element)

remove from the MutableObjectList

minusAssign

Added in 1.4.0

public final void minusAssign(@NonNull E[] elements)

Removes all elements from the MutableObjectList.

minusAssign

public final void minusAssign(@NonNull Iterable<@NonNull E> elements)

Removes all elements from the MutableObjectList.

minusAssign

public final void minusAssign(@NonNull List<@NonNull E> elements)

Removes all elements from the MutableObjectList.

minusAssign

Added in 1.4.0

public final void minusAssign(@NonNull ObjectList<@NonNull E> elements)

Removes all elements from the MutableObjectList.

minusAssign

Added in 1.4.0

public final void minusAssign(@NonNull ScatterSet<@NonNull E> elements)

Removes all elements from the MutableObjectList.

minusAssign

public final void minusAssign(@NonNull Sequence<@NonNull E> elements)

Removes all elements from the MutableObjectList.

plusAssign

Added in 1.4.0

public final void plusAssign(@NonNull E element)

add to the MutableObjectList.

plusAssign

Added in 1.4.0

public final void plusAssign(@NonNull E[] elements)

Adds all elements to the end of the MutableObjectList.

plusAssign

public final void plusAssign(@NonNull Iterable<@NonNull E> elements)

Adds all elements to the end of the MutableObjectList.

plusAssign

public final void plusAssign(@NonNull List<@NonNull E> elements)

Adds all elements to the end of the MutableObjectList.

plusAssign

Added in 1.4.0

public final void plusAssign(@NonNull ObjectList<@NonNull E> elements)

Adds all elements to the end of the MutableObjectList.

plusAssign

Added in 1.4.0

public final void plusAssign(@NonNull ScatterSet<@NonNull E> elements)

Adds all elements to the end of the MutableObjectList.

plusAssign

public final void plusAssign(@NonNull Sequence<@NonNull E> elements)

Adds all elements to the end of the MutableObjectList.

remove

Added in 1.4.0

public final boolean remove(@NonNull E element)

Removes element from the MutableObjectList. If element was in the MutableObjectList and was removed, true will be returned, or false will be returned if the element was not found.