Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) Summary: [Fields](https://developer.android.com/reference/java/util/Vector#lfields) \| [Inherited Fields](https://developer.android.com/reference/java/util/Vector#inhfields) \| [Ctors](https://developer.android.com/reference/java/util/Vector#pubctors) \| [Methods](https://developer.android.com/reference/java/util/Vector#pubmethods) \| [Protected Methods](https://developer.android.com/reference/java/util/Vector#promethods) \| [Inherited Methods](https://developer.android.com/reference/java/util/Vector#inhmethods) # Vector ` public class Vector ` ` ` ` ` ` extends https://developer.android.com/reference/java/util/AbstractList ` ` implements https://developer.android.com/reference/java/lang/Cloneable, https://developer.android.com/reference/java/util/List, https://developer.android.com/reference/java/util/RandomAccess, https://developer.android.com/reference/java/io/Serializable ` |---|---|---|---| | [java.lang.Object](https://developer.android.com/reference/java/lang/Object) |||| | ↳ | [java.util.AbstractCollection](https://developer.android.com/reference/java/util/AbstractCollection)\ ||| | | ↳ | [java.util.AbstractList](https://developer.android.com/reference/java/util/AbstractList)\ || | | | ↳ | java.util.Vector\ | |---| | Known direct subclasses [Stack](https://developer.android.com/reference/java/util/Stack)\ |---|---| | [Stack](https://developer.android.com/reference/java/util/Stack)\ | The `Stack` class represents a last-in-first-out (LIFO) stack of objects. | |
*** ** * ** *** The `Vector` class implements a growable array of objects. Like an array, it contains components that can be accessed using an integer index. However, the size of a `Vector` can grow or shrink as needed to accommodate adding and removing items after the `Vector` has been created. Each vector tries to optimize storage management by maintaining a `capacity` and a `capacityIncrement`. The `capacity` is always at least as large as the vector size; it is usually larger because as components are added to the vector, the vector's storage increases in chunks the size of `capacityIncrement`. An application can increase the capacity of a vector before inserting a large number of components; this reduces the amount of incremental reallocation. The iterators returned by this class's `https://developer.android.com/reference/java/util/Vector#iterator()` and `https://developer.android.com/reference/java/util/Vector#listIterator(int)` methods are *fail-fast* : if the vector is structurally modified at any time after the iterator is created, in any way except through the iterator's own `https://developer.android.com/reference/java/util/ListIterator#remove()` or `https://developer.android.com/reference/java/util/ListIterator#add(E)` methods, the iterator will throw a `https://developer.android.com/reference/java/util/ConcurrentModificationException`. Thus, in the face of concurrent modification, the iterator fails quickly and cleanly, rather than risking arbitrary, non-deterministic behavior at an undetermined time in the future. The `https://developer.android.com/reference/java/util/Enumeration` returned by the `https://developer.android.com/reference/java/util/Vector#elements()` method are *not* fail-fast; if the Vector is structurally modified at any time after the enumeration is created then the results of enumerating are undefined. Note that the fail-fast behavior of an iterator cannot be guaranteed as it is, generally speaking, impossible to make any hard guarantees in the presence of unsynchronized concurrent modification. Fail-fast iterators throw `ConcurrentModificationException` on a best-effort basis. Therefore, it would be wrong to write a program that depended on this exception for its correctness: *the fail-fast behavior of iterators should be used only to detect bugs.* As of the Java 2 platform v1.2, this class was retrofitted to implement the `https://developer.android.com/reference/java/util/List` interface, making it a member of the [Java Collections Framework](https://reference/java/util/package-summary.html#CollectionsFramework). Unlike the new collection implementations, `Vector` is synchronized. If a thread-safe implementation is not needed, it is recommended to use `https://developer.android.com/reference/java/util/ArrayList` in place of `Vector`. **See also:** - `https://developer.android.com/reference/java/util/Collection` - `https://developer.android.com/reference/java/util/LinkedList` ## Summary | ### Fields || |---|---| | ` protected int` | `https://developer.android.com/reference/java/util/Vector#capacityIncrement` The amount by which the capacity of the vector is automatically incremented when its size becomes greater than its capacity. | | ` protected int` | `https://developer.android.com/reference/java/util/Vector#elementCount` The number of valid components in this `Vector` object. | | ` protected https://developer.android.com/reference/java/lang/Object` | `https://developer.android.com/reference/java/util/Vector#elementData` The array buffer into which the components of the vector are stored. | | ### Inherited fields | |---| | From class `https://developer.android.com/reference/java/util/AbstractList` |---|---| | ` protected int` | `https://developer.android.com/reference/java/util/AbstractList#modCount` The number of times this list has been *structurally modified*. | | | ### Public constructors || |---|---| | ` https://developer.android.com/reference/java/util/Vector#Vector()() ` Constructs an empty vector so that its internal data array has size `10` and its standard capacity increment is zero. | | ` https://developer.android.com/reference/java/util/Vector#Vector(int)(int initialCapacity) ` Constructs an empty vector with the specified initial capacity and with its capacity increment equal to zero. | | ` https://developer.android.com/reference/java/util/Vector#Vector(int,%20int)(int initialCapacity, int capacityIncrement) ` Constructs an empty vector with the specified initial capacity and capacity increment. | | ` https://developer.android.com/reference/java/util/Vector#Vector(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Constructs a vector containing the elements of the specified collection, in the order they are returned by the collection's iterator. | | ### Public methods || |---|---| | ` void` | ` https://developer.android.com/reference/java/util/Vector#add(int,%20E)(int index, E element) ` Inserts the specified element at the specified position in this Vector. | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#add(E)(E e) ` Appends the specified element to the end of this Vector. | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#addAll(int,%20java.util.Collection)(int index, https://developer.android.com/reference/java/util/Collection c) ` Inserts all of the elements in the specified Collection into this Vector at the specified position. | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#addAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Appends all of the elements in the specified Collection to the end of this Vector, in the order that they are returned by the specified Collection's Iterator. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#addElement(E)(E obj) ` Adds the specified component to the end of this vector, increasing its size by one. | | ` int` | ` https://developer.android.com/reference/java/util/Vector#capacity()() ` Returns the current capacity of this vector. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#clear()() ` Removes all of the elements from this Vector. | | ` https://developer.android.com/reference/java/lang/Object` | ` https://developer.android.com/reference/java/util/Vector#clone()() ` Returns a clone of this vector. | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#contains(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Returns `true` if this vector contains the specified element. | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#containsAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Returns true if this Vector contains all of the elements in the specified Collection. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#copyInto(java.lang.Object[])(https://developer.android.com/reference/java/lang/Object anArray) ` Copies the components of this vector into the specified array. | | ` E` | ` https://developer.android.com/reference/java/util/Vector#elementAt(int)(int index) ` Returns the component at the specified index. | | ` https://developer.android.com/reference/java/util/Enumeration` | ` https://developer.android.com/reference/java/util/Vector#elements()() ` Returns an enumeration of the components of this vector. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#ensureCapacity(int)(int minCapacity) ` Increases the capacity of this vector, if necessary, to ensure that it can hold at least the number of components specified by the minimum capacity argument. | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Compares the specified Object with this Vector for equality. | | ` E` | ` https://developer.android.com/reference/java/util/Vector#firstElement()() ` Returns the first component (the item at index `0`) of this vector. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#forEach(java.util.function.Consumer)(https://developer.android.com/reference/java/util/function/Consumer action) ` | | ` E` | ` https://developer.android.com/reference/java/util/Vector#get(int)(int index) ` Returns the element at the specified position in this Vector. | | ` int` | ` https://developer.android.com/reference/java/util/Vector#hashCode()() ` Returns the hash code value for this Vector. | | ` int` | ` https://developer.android.com/reference/java/util/Vector#indexOf(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Returns the index of the first occurrence of the specified element in this vector, or -1 if this vector does not contain the element. | | ` int` | ` https://developer.android.com/reference/java/util/Vector#indexOf(java.lang.Object,%20int)(https://developer.android.com/reference/java/lang/Object o, int index) ` Returns the index of the first occurrence of the specified element in this vector, searching forwards from `index`, or returns -1 if the element is not found. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#insertElementAt(E,%20int)(E obj, int index) ` Inserts the specified object as a component in this vector at the specified `index`. | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#isEmpty()() ` Tests if this vector has no components. | | ` https://developer.android.com/reference/java/util/Iterator` | ` https://developer.android.com/reference/java/util/Vector#iterator()() ` Returns an iterator over the elements in this list in proper sequence. | | ` E` | ` https://developer.android.com/reference/java/util/Vector#lastElement()() ` Returns the last component of the vector. | | ` int` | ` https://developer.android.com/reference/java/util/Vector#lastIndexOf(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Returns the index of the last occurrence of the specified element in this vector, or -1 if this vector does not contain the element. | | ` int` | ` https://developer.android.com/reference/java/util/Vector#lastIndexOf(java.lang.Object,%20int)(https://developer.android.com/reference/java/lang/Object o, int index) ` Returns the index of the last occurrence of the specified element in this vector, searching backwards from `index`, or returns -1 if the element is not found. | | ` https://developer.android.com/reference/java/util/ListIterator` | ` https://developer.android.com/reference/java/util/Vector#listIterator(int)(int index) ` Returns a list iterator over the elements in this list (in proper sequence), starting at the specified position in the list. | | ` https://developer.android.com/reference/java/util/ListIterator` | ` https://developer.android.com/reference/java/util/Vector#listIterator()() ` Returns a list iterator over the elements in this list (in proper sequence). | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#remove(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Removes the first occurrence of the specified element in this Vector If the Vector does not contain the element, it is unchanged. | | ` E` | ` https://developer.android.com/reference/java/util/Vector#remove(int)(int index) ` Removes the element at the specified position in this Vector. | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#removeAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Removes from this Vector all of its elements that are contained in the specified Collection. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#removeAllElements()() ` Removes all components from this vector and sets its size to zero. | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#removeElement(java.lang.Object)(https://developer.android.com/reference/java/lang/Object obj) ` Removes the first (lowest-indexed) occurrence of the argument from this vector. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#removeElementAt(int)(int index) ` Deletes the component at the specified index. | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#removeIf(java.util.function.Predicate)(https://developer.android.com/reference/java/util/function/Predicate filter) ` Removes all of the elements of this collection that satisfy the given predicate (optional operation). | | ` void` | ` https://developer.android.com/reference/java/util/Vector#replaceAll(java.util.function.UnaryOperator)(https://developer.android.com/reference/java/util/function/UnaryOperator operator) ` Replaces each element of this list with the result of applying the operator to that element (optional operation). | | ` boolean` | ` https://developer.android.com/reference/java/util/Vector#retainAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Retains only the elements in this Vector that are contained in the specified Collection. | | ` E` | ` https://developer.android.com/reference/java/util/Vector#set(int,%20E)(int index, E element) ` Replaces the element at the specified position in this Vector with the specified element. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#setElementAt(E,%20int)(E obj, int index) ` Sets the component at the specified `index` of this vector to be the specified object. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#setSize(int)(int newSize) ` Sets the size of this vector. | | ` int` | ` https://developer.android.com/reference/java/util/Vector#size()() ` Returns the number of components in this vector. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#sort(java.util.Comparator)(https://developer.android.com/reference/java/util/Comparator c) ` Sorts this list according to the order induced by the specified `https://developer.android.com/reference/java/util/Comparator` (optional operation). | | ` https://developer.android.com/reference/java/util/Spliterator` | ` https://developer.android.com/reference/java/util/Vector#spliterator()() ` Creates a *[late-binding](https://developer.android.com/reference/java/util/Spliterator#binding)* and *fail-fast* `https://developer.android.com/reference/java/util/Spliterator` over the elements in this list. | | ` https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/Vector#subList(int,%20int)(int fromIndex, int toIndex) ` Returns a view of the portion of this List between fromIndex, inclusive, and toIndex, exclusive. | | ` https://developer.android.com/reference/java/lang/Object` | ` https://developer.android.com/reference/java/util/Vector#toArray()() ` Returns an array containing all of the elements in this Vector in the correct order. | | ` T[]` | ` https://developer.android.com/reference/java/util/Vector#toArray(T[])(T[] a) ` Returns an array containing all of the elements in this Vector in the correct order; the runtime type of the returned array is that of the specified array. | | ` https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/java/util/Vector#toString()() ` Returns a string representation of this Vector, containing the String representation of each element. | | ` void` | ` https://developer.android.com/reference/java/util/Vector#trimToSize()() ` Trims the capacity of this vector to be the vector's current size. | | ### Protected methods || |---|---| | ` void` | ` https://developer.android.com/reference/java/util/Vector#removeRange(int,%20int)(int fromIndex, int toIndex) ` Removes from this list all of the elements whose index is between `fromIndex`, inclusive, and `toIndex`, exclusive. | | ### Inherited methods | |---|---| | From class ` https://developer.android.com/reference/java/util/AbstractList ` |---|---| | ` void` | ` https://developer.android.com/reference/java/util/AbstractList#add(int,%20E)(int index, E element) ` Inserts the specified element at the specified position in this list (optional operation). | | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractList#add(E)(E e) ` Appends the specified element to the end of this list (optional operation). | | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractList#addAll(int,%20java.util.Collection)(int index, https://developer.android.com/reference/java/util/Collection c) ` Inserts all of the elements in the specified collection into this list at the specified position (optional operation). | | ` void` | ` https://developer.android.com/reference/java/util/AbstractList#clear()() ` Removes all of the elements from this list (optional operation). | | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractList#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Compares the specified object with this list for equality. | | ` abstract E` | ` https://developer.android.com/reference/java/util/AbstractList#get(int)(int index) ` Returns the element at the specified position in this list. | | ` int` | ` https://developer.android.com/reference/java/util/AbstractList#hashCode()() ` Returns the hash code value for this list. | | ` int` | ` https://developer.android.com/reference/java/util/AbstractList#indexOf(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element. | | ` https://developer.android.com/reference/java/util/Iterator` | ` https://developer.android.com/reference/java/util/AbstractList#iterator()() ` Returns an iterator over the elements in this list in proper sequence. | | ` int` | ` https://developer.android.com/reference/java/util/AbstractList#lastIndexOf(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Returns the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element. | | ` https://developer.android.com/reference/java/util/ListIterator` | ` https://developer.android.com/reference/java/util/AbstractList#listIterator(int)(int index) ` Returns a list iterator over the elements in this list (in proper sequence), starting at the specified position in the list. | | ` https://developer.android.com/reference/java/util/ListIterator` | ` https://developer.android.com/reference/java/util/AbstractList#listIterator()() ` Returns a list iterator over the elements in this list (in proper sequence). | | ` E` | ` https://developer.android.com/reference/java/util/AbstractList#remove(int)(int index) ` Removes the element at the specified position in this list (optional operation). | | ` void` | ` https://developer.android.com/reference/java/util/AbstractList#removeRange(int,%20int)(int fromIndex, int toIndex) ` Removes from this list all of the elements whose index is between `fromIndex`, inclusive, and `toIndex`, exclusive. | | ` E` | ` https://developer.android.com/reference/java/util/AbstractList#set(int,%20E)(int index, E element) ` Replaces the element at the specified position in this list with the specified element (optional operation). | | ` https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/AbstractList#subList(int,%20int)(int fromIndex, int toIndex) ` Returns a view of the portion of this list between the specified `fromIndex`, inclusive, and `toIndex`, exclusive. | || | From class ` https://developer.android.com/reference/java/util/AbstractCollection ` |---|---| | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractCollection#add(E)(E e) ` Ensures that this collection contains the specified element (optional operation). | | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractCollection#addAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Adds all of the elements in the specified collection to this collection (optional operation). | | ` void` | ` https://developer.android.com/reference/java/util/AbstractCollection#clear()() ` Removes all of the elements from this collection (optional operation). | | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractCollection#contains(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Returns `true` if this collection contains the specified element. | | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractCollection#containsAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Returns `true` if this collection contains all of the elements in the specified collection. | | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractCollection#isEmpty()() ` Returns `true` if this collection contains no elements. | | ` abstract https://developer.android.com/reference/java/util/Iterator` | ` https://developer.android.com/reference/java/util/AbstractCollection#iterator()() ` Returns an iterator over the elements contained in this collection. | | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractCollection#remove(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Removes a single instance of the specified element from this collection, if it is present (optional operation). | | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractCollection#removeAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Removes all of this collection's elements that are also contained in the specified collection (optional operation). | | ` boolean` | ` https://developer.android.com/reference/java/util/AbstractCollection#retainAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Retains only the elements in this collection that are contained in the specified collection (optional operation). | | ` abstract int` | ` https://developer.android.com/reference/java/util/AbstractCollection#size()() ` Returns the number of elements in this collection. | | ` T[]` | ` https://developer.android.com/reference/java/util/AbstractCollection#toArray(T[])(T[] a) ` Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array. | | ` https://developer.android.com/reference/java/lang/Object` | ` https://developer.android.com/reference/java/util/AbstractCollection#toArray()() ` Returns an array containing all of the elements in this collection. | | ` https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/java/util/AbstractCollection#toString()() ` Returns a string representation of this collection. | || | From class ` https://developer.android.com/reference/java/lang/Object ` |---|---| | ` https://developer.android.com/reference/java/lang/Object` | ` https://developer.android.com/reference/java/lang/Object#clone()() ` Creates and returns a copy of this object. | | ` boolean` | ` https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object obj) ` Indicates whether some other object is "equal to" this one. | | ` void` | ` https://developer.android.com/reference/java/lang/Object#finalize()() ` Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. | | ` final https://developer.android.com/reference/java/lang/Class` | ` https://developer.android.com/reference/java/lang/Object#getClass()() ` Returns the runtime class of this `Object`. | | ` int` | ` https://developer.android.com/reference/java/lang/Object#hashCode()() ` Returns a hash code value for the object. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#notify()() ` Wakes up a single thread that is waiting on this object's monitor. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#notifyAll()() ` Wakes up all threads that are waiting on this object's monitor. | | ` https://developer.android.com/reference/java/lang/String` | ` https://developer.android.com/reference/java/lang/Object#toString()() ` Returns a string representation of the object. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#wait(long,%20int)(long timeoutMillis, int nanos) ` Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*, or until a certain amount of real time has elapsed. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#wait(long)(long timeoutMillis) ` Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*, or until a certain amount of real time has elapsed. | | ` final void` | ` https://developer.android.com/reference/java/lang/Object#wait()() ` Causes the current thread to wait until it is awakened, typically by being *notified* or *interrupted*. | || | From interface ` https://developer.android.com/reference/java/util/List ` |---|---| | ` abstract boolean` | ` https://developer.android.com/reference/java/util/List#add(E)(E e) ` Appends the specified element to the end of this list (optional operation). | | ` abstract void` | ` https://developer.android.com/reference/java/util/List#add(int,%20E)(int index, E element) ` Inserts the specified element at the specified position in this list (optional operation). | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/List#addAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection 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). | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/List#addAll(int,%20java.util.Collection)(int index, https://developer.android.com/reference/java/util/Collection c) ` Inserts all of the elements in the specified collection into this list at the specified position (optional operation). | | ` default void` | ` https://developer.android.com/reference/java/util/List#addFirst(E)(E e) ` Adds an element as the first element of this collection (optional operation). | | ` default void` | ` https://developer.android.com/reference/java/util/List#addLast(E)(E e) ` Adds an element as the last element of this collection (optional operation). | | ` abstract void` | ` https://developer.android.com/reference/java/util/List#clear()() ` Removes all of the elements from this list (optional operation). | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/List#contains(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Returns `true` if this list contains the specified element. | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/List#containsAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Returns `true` if this list contains all of the elements of the specified collection. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#copyOf(java.util.Collection)(https://developer.android.com/reference/java/util/Collection coll) ` Returns an [unmodifiable List](https://developer.android.com/reference/java/util/Vector#unmodifiable) containing the elements of the given Collection, in its iteration order. | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/List#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Compares the specified object with this list for equality. | | ` abstract E` | ` https://developer.android.com/reference/java/util/List#get(int)(int index) ` Returns the element at the specified position in this list. | | ` default E` | ` https://developer.android.com/reference/java/util/List#getFirst()() ` Gets the first element of this collection. | | ` default E` | ` https://developer.android.com/reference/java/util/List#getLast()() ` Gets the last element of this collection. | | ` abstract int` | ` https://developer.android.com/reference/java/util/List#hashCode()() ` Returns the hash code value for this list. | | ` abstract int` | ` https://developer.android.com/reference/java/util/List#indexOf(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Returns the index of the first occurrence of the specified element in this list, or -1 if this list does not contain the element. | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/List#isEmpty()() ` Returns `true` if this list contains no elements. | | ` abstract https://developer.android.com/reference/java/util/Iterator` | ` https://developer.android.com/reference/java/util/List#iterator()() ` Returns an iterator over the elements in this list in proper sequence. | | ` abstract int` | ` https://developer.android.com/reference/java/util/List#lastIndexOf(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Returns the index of the last occurrence of the specified element in this list, or -1 if this list does not contain the element. | | ` abstract https://developer.android.com/reference/java/util/ListIterator` | ` https://developer.android.com/reference/java/util/List#listIterator(int)(int index) ` Returns a list iterator over the elements in this list (in proper sequence), starting at the specified position in the list. | | ` abstract https://developer.android.com/reference/java/util/ListIterator` | ` https://developer.android.com/reference/java/util/List#listIterator()() ` Returns a list iterator over the elements in this list (in proper sequence). | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E,%20E,%20E)(E e1, E e2, E e3) ` Returns an unmodifiable list containing three elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E,%20E,%20E,%20E,%20E,%20E,%20E,%20E,%20E)(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9) ` Returns an unmodifiable list containing nine elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E,%20E,%20E,%20E,%20E)(E e1, E e2, E e3, E e4, E e5) ` Returns an unmodifiable list containing five elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E,%20E,%20E,%20E,%20E,%20E)(E e1, E e2, E e3, E e4, E e5, E e6) ` Returns an unmodifiable list containing six elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E,%20E,%20E,%20E,%20E,%20E,%20E,%20E)(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8) ` Returns an unmodifiable list containing eight elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E[])(E... elements) ` Returns an unmodifiable list containing an arbitrary number of elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of()() ` Returns an unmodifiable list containing zero elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E,%20E,%20E,%20E,%20E,%20E,%20E,%20E,%20E,%20E)(E e1, E e2, E e3, E e4, E e5, E e6, E e7, E e8, E e9, E e10) ` Returns an unmodifiable list containing ten elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E,%20E)(E e1, E e2) ` Returns an unmodifiable list containing two elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E,%20E,%20E,%20E,%20E,%20E,%20E)(E e1, E e2, E e3, E e4, E e5, E e6, E e7) ` Returns an unmodifiable list containing seven elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E,%20E,%20E,%20E)(E e1, E e2, E e3, E e4) ` Returns an unmodifiable list containing four elements. | | ` static https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#of(E)(E e1) ` Returns an unmodifiable list containing one element. | | ` abstract E` | ` https://developer.android.com/reference/java/util/List#remove(int)(int index) ` Removes the element at the specified position in this list (optional operation). | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/List#remove(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Removes the first occurrence of the specified element from this list, if it is present (optional operation). | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/List#removeAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Removes from this list all of its elements that are contained in the specified collection (optional operation). | | ` default E` | ` https://developer.android.com/reference/java/util/List#removeFirst()() ` Removes and returns the first element of this collection (optional operation). | | ` default E` | ` https://developer.android.com/reference/java/util/List#removeLast()() ` Removes and returns the last element of this collection (optional operation). | | ` default void` | ` https://developer.android.com/reference/java/util/List#replaceAll(java.util.function.UnaryOperator)(https://developer.android.com/reference/java/util/function/UnaryOperator operator) ` Replaces each element of this list with the result of applying the operator to that element (optional operation). | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/List#retainAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Retains only the elements in this list that are contained in the specified collection (optional operation). | | ` default https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#reversed()() ` Returns a reverse-ordered [view](https://developer.android.com/reference/java/util/Collection#view) of this collection. | | ` abstract E` | ` https://developer.android.com/reference/java/util/List#set(int,%20E)(int index, E element) ` Replaces the element at the specified position in this list with the specified element (optional operation). | | ` abstract int` | ` https://developer.android.com/reference/java/util/List#size()() ` Returns the number of elements in this list. | | ` default void` | ` https://developer.android.com/reference/java/util/List#sort(java.util.Comparator)(https://developer.android.com/reference/java/util/Comparator c) ` Sorts this list according to the order induced by the specified `https://developer.android.com/reference/java/util/Comparator` (optional operation). | | ` default https://developer.android.com/reference/java/util/Spliterator` | ` https://developer.android.com/reference/java/util/List#spliterator()() ` Creates a `https://developer.android.com/reference/java/util/Spliterator` over the elements in this list. | | ` abstract https://developer.android.com/reference/java/util/List` | ` https://developer.android.com/reference/java/util/List#subList(int,%20int)(int fromIndex, int toIndex) ` Returns a view of the portion of this list between the specified `fromIndex`, inclusive, and `toIndex`, exclusive. | | ` abstract https://developer.android.com/reference/java/lang/Object` | ` https://developer.android.com/reference/java/util/List#toArray()() ` Returns an array containing all of the elements in this list in proper sequence (from first to last element). | | ` abstract T[]` | ` https://developer.android.com/reference/java/util/List#toArray(T[])(T[] 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. | || | From interface ` https://developer.android.com/reference/java/util/Collection ` |---|---| | ` abstract boolean` | ` https://developer.android.com/reference/java/util/Collection#add(E)(E e) ` Ensures that this collection contains the specified element (optional operation). | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/Collection#addAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Adds all of the elements in the specified collection to this collection (optional operation). | | ` abstract void` | ` https://developer.android.com/reference/java/util/Collection#clear()() ` Removes all of the elements from this collection (optional operation). | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/Collection#contains(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Returns `true` if this collection contains the specified element. | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/Collection#containsAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Returns `true` if this collection contains all of the elements in the specified collection. | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/Collection#equals(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Compares the specified object with this collection for equality. | | ` abstract int` | ` https://developer.android.com/reference/java/util/Collection#hashCode()() ` Returns the hash code value for this collection. | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/Collection#isEmpty()() ` Returns `true` if this collection contains no elements. | | ` abstract https://developer.android.com/reference/java/util/Iterator` | ` https://developer.android.com/reference/java/util/Collection#iterator()() ` Returns an iterator over the elements in this collection. | | ` default https://developer.android.com/reference/java/util/stream/Stream` | ` https://developer.android.com/reference/java/util/Collection#parallelStream()() ` Returns a possibly parallel `Stream` with this collection as its source. | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/Collection#remove(java.lang.Object)(https://developer.android.com/reference/java/lang/Object o) ` Removes a single instance of the specified element from this collection, if it is present (optional operation). | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/Collection#removeAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Removes all of this collection's elements that are also contained in the specified collection (optional operation). | | ` default boolean` | ` https://developer.android.com/reference/java/util/Collection#removeIf(java.util.function.Predicate)(https://developer.android.com/reference/java/util/function/Predicate filter) ` Removes all of the elements of this collection that satisfy the given predicate (optional operation). | | ` abstract boolean` | ` https://developer.android.com/reference/java/util/Collection#retainAll(java.util.Collection)(https://developer.android.com/reference/java/util/Collection c) ` Retains only the elements in this collection that are contained in the specified collection (optional operation). | | ` abstract int` | ` https://developer.android.com/reference/java/util/Collection#size()() ` Returns the number of elements in this collection. | | ` default https://developer.android.com/reference/java/util/Spliterator` | ` https://developer.android.com/reference/java/util/Collection#spliterator()() ` Creates a `https://developer.android.com/reference/java/util/Spliterator` over the elements in this collection. | | ` default https://developer.android.com/reference/java/util/stream/Stream` | ` https://developer.android.com/reference/java/util/Collection#stream()() ` Returns a sequential `Stream` with this collection as its source. | | ` abstract T[]` | ` https://developer.android.com/reference/java/util/Collection#toArray(T[])(T[] a) ` Returns an array containing all of the elements in this collection; the runtime type of the returned array is that of the specified array. | | ` abstract https://developer.android.com/reference/java/lang/Object` | ` https://developer.android.com/reference/java/util/Collection#toArray()() ` Returns an array containing all of the elements in this collection. | | ` default T[]` | ` https://developer.android.com/reference/java/util/Collection#toArray(java.util.function.IntFunction)(https://developer.android.com/reference/java/util/function/IntFunction generator) ` Returns an array containing all of the elements in this collection, using the provided `generator` function to allocate the returned array. | || | From interface ` https://developer.android.com/reference/java/util/SequencedCollection ` |---|---| | ` default void` | ` https://developer.android.com/reference/java/util/SequencedCollection#addFirst(E)(E e) ` Adds an element as the first element of this collection (optional operation). | | ` default void` | ` https://developer.android.com/reference/java/util/SequencedCollection#addLast(E)(E e) ` Adds an element as the last element of this collection (optional operation). | | ` default E` | ` https://developer.android.com/reference/java/util/SequencedCollection#getFirst()() ` Gets the first element of this collection. | | ` default E` | ` https://developer.android.com/reference/java/util/SequencedCollection#getLast()() ` Gets the last element of this collection. | | ` default E` | ` https://developer.android.com/reference/java/util/SequencedCollection#removeFirst()() ` Removes and returns the first element of this collection (optional operation). | | ` default E` | ` https://developer.android.com/reference/java/util/SequencedCollection#removeLast()() ` Removes and returns the last element of this collection (optional operation). | | ` abstract https://developer.android.com/reference/java/util/SequencedCollection` | ` https://developer.android.com/reference/java/util/SequencedCollection#reversed()() ` Returns a reverse-ordered [view](https://developer.android.com/reference/java/util/Collection#view) of this collection. | || | From interface ` https://developer.android.com/reference/java/lang/Iterable ` |---|---| | ` default void` | ` https://developer.android.com/reference/java/lang/Iterable#forEach(java.util.function.Consumer)(https://developer.android.com/reference/java/util/function/Consumer action) ` Performs the given action for each element of the `Iterable` until all elements have been processed or the action throws an exception. | | ` abstract https://developer.android.com/reference/java/util/Iterator` | ` https://developer.android.com/reference/java/lang/Iterable#iterator()() ` Returns an iterator over elements of type `T`. | | ` default https://developer.android.com/reference/java/util/Spliterator` | ` https://developer.android.com/reference/java/lang/Iterable#spliterator()() ` Creates a `https://developer.android.com/reference/java/util/Spliterator` over the elements described by this `Iterable`. | || ## Fields ### capacityIncrement Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` protected int capacityIncrement ``` The amount by which the capacity of the vector is automatically incremented when its size becomes greater than its capacity. If the capacity increment is less than or equal to zero, the capacity of the vector is doubled each time it needs to grow.
### elementCount Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` protected int elementCount ``` The number of valid components in this `Vector` object. Components `elementData[0]` through `elementData[elementCount-1]` are the actual items.
### elementData Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` protected Object[] elementData ``` The array buffer into which the components of the vector are stored. The capacity of the vector is the length of this array buffer, and is at least large enough to contain all the vector's elements. Any array elements following the last element in the Vector are null.
## Public constructors ### Vector Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public Vector () ``` Constructs an empty vector so that its internal data array has size `10` and its standard capacity increment is zero.
### Vector Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public Vector (int initialCapacity) ``` Constructs an empty vector with the specified initial capacity and with its capacity increment equal to zero.
| Parameters || |---|---| | `initialCapacity` | `int`: the initial capacity of the vector
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/IllegalArgumentException` | if the specified initial capacity is negative | ### Vector Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public Vector (int initialCapacity, int capacityIncrement) ``` Constructs an empty vector with the specified initial capacity and capacity increment.
| Parameters || |---|---| | `initialCapacity` | `int`: the initial capacity of the vector
| | `capacityIncrement` | `int`: the amount by which the capacity is increased when the vector overflows
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/IllegalArgumentException` | if the specified initial capacity is negative | ### Vector Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public Vector (Collection c) ``` Constructs a vector containing the elements of the specified collection, in the order they are returned by the collection's iterator.
| Parameters || |---|---| | `c` | `Collection`: the collection whose elements are to be placed into this vector
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/NullPointerException` | if the specified collection is null | ## Public methods ### add Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void add (int index, E element) ``` Inserts the specified element at the specified position in this Vector. Shifts the element currently at that position (if any) and any subsequent elements to the right (adds one to their indices).
| Parameters || |---|---| | `index` | `int`: index at which the specified element is to be inserted
| | `element` | `E`: element to be inserted
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayIndexOutOfBoundsException` | if the index is out of range (`index < 0 || index > size()`) | ### add Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean add (E e) ``` Appends the specified element to the end of this Vector.
| Parameters || |---|---| | `e` | `E`: element to be appended to this Vector
| | Returns || |---|---| | `boolean` | `true` (as specified by `https://developer.android.com/reference/java/util/Collection#add(E)`)
| ### addAll Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean addAll (int index, Collection c) ``` Inserts all of the elements in the specified Collection into this Vector 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 the Vector in the order that they are returned by the specified Collection's iterator.
| Parameters || |---|---| | `index` | `int`: index at which to insert the first element from the specified collection
| | `c` | `Collection`: elements to be inserted into this Vector
| | Returns || |---|---| | `boolean` | `true` if this Vector changed as a result of the call
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayIndexOutOfBoundsException` | if the index is out of range (`index < 0 || index > size()`) | | `https://developer.android.com/reference/java/lang/NullPointerException` | if the specified collection is null | ### addAll Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean addAll (Collection c) ``` Appends all of the elements in the specified Collection to the end of this Vector, in the order that they are returned by the specified Collection's Iterator. The behavior of this operation is undefined if the specified Collection is modified while the operation is in progress. (This implies that the behavior of this call is undefined if the specified Collection is this Vector, and this Vector is nonempty.)
| Parameters || |---|---| | `c` | `Collection`: elements to be inserted into this Vector
| | Returns || |---|---| | `boolean` | `true` if this Vector changed as a result of the call
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/NullPointerException` | if the specified collection is null | ### addElement Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void addElement (E obj) ``` Adds the specified component to the end of this vector, increasing its size by one. The capacity of this vector is increased if its size becomes greater than its capacity. This method is identical in functionality to the `https://developer.android.com/reference/java/util/Vector#add(E)` method (which is part of the `https://developer.android.com/reference/java/util/List` interface).
| Parameters || |---|---| | `obj` | `E`: the component to be added
| ### capacity Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public int capacity () ``` Returns the current capacity of this vector.
| Returns || |---|---| | `int` | the current capacity (the length of its internal data array, kept in the field `elementData` of this vector)
| ### clear Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void clear () ``` Removes all of the elements from this Vector. The Vector will be empty after this call returns (unless it throws an exception).
### clone Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public Object clone () ``` Returns a clone of this vector. The copy will contain a reference to a clone of the internal data array, not a reference to the original internal data array of this `Vector` object.
| Returns || |---|---| | `https://developer.android.com/reference/java/lang/Object` | a clone of this vector
| ### contains Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean contains (Object o) ``` Returns `true` if this vector contains the specified element. More formally, returns `true` if and only if this vector contains at least one element `e` such that `Objects.equals(o, e)`.
| Parameters || |---|---| | `o` | `Object`: element whose presence in this vector is to be tested
| | Returns || |---|---| | `boolean` | `true` if this vector contains the specified element
| ### containsAll Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean containsAll (Collection c) ``` Returns true if this Vector contains all of the elements in the specified Collection.
| Parameters || |---|---| | `c` | `Collection`: a collection whose elements will be tested for containment in this Vector
| | Returns || |---|---| | `boolean` | true if this Vector contains all of the elements in the specified collection
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/NullPointerException` | if the specified collection is null | ### copyInto Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void copyInto (Object[] anArray) ``` Copies the components of this vector into the specified array. The item at index `k` in this vector is copied into component `k` of `anArray`.
| Parameters || |---|---| | `anArray` | `Object`: the array into which the components get copied
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayStoreException` | if a component of this vector is not of a runtime type that can be stored in the specified array | | `https://developer.android.com/reference/java/lang/IndexOutOfBoundsException` | if the specified array is not large enough to hold all the components of this vector | | `https://developer.android.com/reference/java/lang/NullPointerException` | if the given array is null | **See also:** - `https://developer.android.com/reference/java/util/Vector#toArray(T[])` ### elementAt Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public E elementAt (int index) ``` Returns the component at the specified index. This method is identical in functionality to the `https://developer.android.com/reference/java/util/Vector#get(int)` method (which is part of the `https://developer.android.com/reference/java/util/List` interface).
| Parameters || |---|---| | `index` | `int`: an index into this vector
| | Returns || |---|---| | `E` | the component at the specified index
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayIndexOutOfBoundsException` | if the index is out of range (`index < 0 || index >= size()`) | ### elements Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public Enumeration elements () ``` Returns an enumeration of the components of this vector. The returned `Enumeration` object will generate all items in this vector. The first item generated is the item at index `0`, then the item at index `1`, and so on. If the vector is structurally modified while enumerating over the elements then the results of enumerating are undefined.
| Returns || |---|---| | `https://developer.android.com/reference/java/util/Enumeration` | an enumeration of the components of this vector
| **See also:** - `https://developer.android.com/reference/java/util/Iterator` ### ensureCapacity Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void ensureCapacity (int minCapacity) ``` Increases the capacity of this vector, if necessary, to ensure that it can hold at least the number of components specified by the minimum capacity argument. If the current capacity of this vector is less than `minCapacity`, then its capacity is increased by replacing its internal data array, kept in the field `elementData`, with a larger one. The size of the new data array will be the old size plus `capacityIncrement`, unless the value of `capacityIncrement` is less than or equal to zero, in which case the new capacity will be twice the old capacity; but if this new size is still smaller than `minCapacity`, then the new capacity will be `minCapacity`.
| Parameters || |---|---| | `minCapacity` | `int`: the desired minimum capacity
| ### equals Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean equals (Object o) ``` Compares the specified Object with this Vector for equality. Returns true if and only if the specified Object is also a List, both Lists have the same size, and all corresponding pairs of elements in the two Lists are *equal* . (Two elements `e1` and `e2` are *equal* if `Objects.equals(e1, e2)`.) In other words, two Lists are defined to be equal if they contain the same elements in the same order.
| Parameters || |---|---| | `o` | `Object`: the Object to be compared for equality with this Vector
| | Returns || |---|---| | `boolean` | true if the specified Object is equal to this Vector
| ### firstElement Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public E firstElement () ``` Returns the first component (the item at index `0`) of this vector.
| Returns || |---|---| | `E` | the first component of this vector
| | Throws || |---|---| | `https://developer.android.com/reference/java/util/NoSuchElementException` | if this vector has no components | ### forEach Added in [API level 24](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void forEach (Consumer action) ```

| Parameters || |---|---| | `action` | `Consumer`
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/NullPointerException` | | ### get Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public E get (int index) ``` Returns the element at the specified position in this Vector.
| Parameters || |---|---| | `index` | `int`: index of the element to return
| | Returns || |---|---| | `E` | object at the specified index
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayIndexOutOfBoundsException` | if the index is out of range (`index < 0 || index >= size()`) | ### hashCode Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public int hashCode () ``` Returns the hash code value for this Vector.
| Returns || |---|---| | `int` | the hash code value for this list
| ### indexOf Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public int indexOf (Object o) ``` Returns the index of the first occurrence of the specified element in this vector, or -1 if this vector does not contain the element. More formally, returns the lowest index `i` such that `Objects.equals(o, get(i))`, or -1 if there is no such index.
| Parameters || |---|---| | `o` | `Object`: element to search for
| | Returns || |---|---| | `int` | the index of the first occurrence of the specified element in this vector, or -1 if this vector does not contain the element
| ### indexOf Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public int indexOf (Object o, int index) ``` Returns the index of the first occurrence of the specified element in this vector, searching forwards from `index`, or returns -1 if the element is not found. More formally, returns the lowest index `i` such that `(i >= index && Objects.equals(o, get(i)))`, or -1 if there is no such index.
| Parameters || |---|---| | `o` | `Object`: element to search for
| | `index` | `int`: index to start searching from
| | Returns || |---|---| | `int` | the index of the first occurrence of the element in this vector at position `index` or later in the vector; `-1` if the element is not found.
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/IndexOutOfBoundsException` | if the specified index is negative | **See also:** - `https://developer.android.com/reference/java/lang/Object#equals(java.lang.Object)` ### insertElementAt Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void insertElementAt (E obj, int index) ``` Inserts the specified object as a component in this vector at the specified `index`. Each component in this vector with an index greater or equal to the specified `index` is shifted upward to have an index one greater than the value it had previously. The index must be a value greater than or equal to `0` and less than or equal to the current size of the vector. (If the index is equal to the current size of the vector, the new element is appended to the Vector.) This method is identical in functionality to the `https://developer.android.com/reference/java/util/Vector#add(int,%20E)` method (which is part of the `https://developer.android.com/reference/java/util/List` interface). Note that the `add` method reverses the order of the parameters, to more closely match array usage.
| Parameters || |---|---| | `obj` | `E`: the component to insert
| | `index` | `int`: where to insert the new component
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayIndexOutOfBoundsException` | if the index is out of range (`index < 0 || index > size()`) | ### isEmpty Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean isEmpty () ``` Tests if this vector has no components.
| Returns || |---|---| | `boolean` | `true` if and only if this vector has no components, that is, its size is zero; `false` otherwise.
| ### iterator Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public Iterator iterator () ``` Returns an iterator over the elements in this list in proper sequence. The returned iterator is [*fail-fast*](https://developer.android.com/reference/java/util/Vector#fail-fast).
| Returns || |---|---| | `https://developer.android.com/reference/java/util/Iterator` | an iterator over the elements in this list in proper sequence
| ### lastElement Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public E lastElement () ``` Returns the last component of the vector.
| Returns || |---|---| | `E` | the last component of the vector, i.e., the component at index `size() - 1`
| | Throws || |---|---| | `https://developer.android.com/reference/java/util/NoSuchElementException` | if this vector is empty | ### lastIndexOf Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public int lastIndexOf (Object o) ``` Returns the index of the last occurrence of the specified element in this vector, or -1 if this vector does not contain the element. More formally, returns the highest index `i` such that `Objects.equals(o, get(i))`, or -1 if there is no such index.
| Parameters || |---|---| | `o` | `Object`: element to search for
| | Returns || |---|---| | `int` | the index of the last occurrence of the specified element in this vector, or -1 if this vector does not contain the element
| ### lastIndexOf Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public int lastIndexOf (Object o, int index) ``` Returns the index of the last occurrence of the specified element in this vector, searching backwards from `index`, or returns -1 if the element is not found. More formally, returns the highest index `i` such that `(i <= index && Objects.equals(o, get(i)))`, or -1 if there is no such index.
| Parameters || |---|---| | `o` | `Object`: element to search for
| | `index` | `int`: index to start searching backwards from
| | Returns || |---|---| | `int` | the index of the last occurrence of the element at position less than or equal to `index` in this vector; -1 if the element is not found.
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/IndexOutOfBoundsException` | if the specified index is greater than or equal to the current size of this vector | ### listIterator Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public ListIterator listIterator (int 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 `https://developer.android.com/reference/java/util/ListIterator#next()`. An initial call to `https://developer.android.com/reference/java/util/ListIterator#previous()` would return the element with the specified index minus one. The returned list iterator is [*fail-fast*](https://developer.android.com/reference/java/util/Vector#fail-fast).
| Parameters || |---|---| | `index` | `int`: index of the first element to be returned from the list iterator (by a call to `https://developer.android.com/reference/java/util/ListIterator#next()`)
| | Returns || |---|---| | `https://developer.android.com/reference/java/util/ListIterator` | a list iterator over the elements in this list (in proper sequence), starting at the specified position in the list
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/IndexOutOfBoundsException` | | ### listIterator Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public ListIterator listIterator () ``` Returns a list iterator over the elements in this list (in proper sequence). The returned list iterator is [*fail-fast*](https://developer.android.com/reference/java/util/Vector#fail-fast).
| Returns || |---|---| | `https://developer.android.com/reference/java/util/ListIterator` | a list iterator over the elements in this list (in proper sequence)
| **See also:** - `https://developer.android.com/reference/java/util/Vector#listIterator(int)` ### remove Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean remove (Object o) ``` Removes the first occurrence of the specified element in this Vector If the Vector does not contain the element, it is unchanged. More formally, removes the element with the lowest index i such that `Objects.equals(o, get(i))` (if such an element exists).
| Parameters || |---|---| | `o` | `Object`: element to be removed from this Vector, if present
| | Returns || |---|---| | `boolean` | true if the Vector contained the specified element
| ### remove Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public E remove (int index) ``` Removes the element at the specified position in this Vector. Shifts any subsequent elements to the left (subtracts one from their indices). Returns the element that was removed from the Vector.
| Parameters || |---|---| | `index` | `int`: the index of the element to be removed
| | Returns || |---|---| | `E` | element that was removed
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayIndexOutOfBoundsException` | if the index is out of range (`index < 0 || index >= size()`) | ### removeAll Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean removeAll (Collection c) ``` Removes from this Vector all of its elements that are contained in the specified Collection.
| Parameters || |---|---| | `c` | `Collection`: a collection of elements to be removed from the Vector
| | Returns || |---|---| | `boolean` | true if this Vector changed as a result of the call
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ClassCastException` | if the types of one or more elements in this vector are incompatible with the specified collection ([optional](https://developer.android.com/reference/java/util/Collection#optional-restrictions)) | | `https://developer.android.com/reference/java/lang/NullPointerException` | if this vector contains one or more null elements and the specified collection does not support null elements ([optional](https://developer.android.com/reference/java/util/Collection#optional-restrictions)), or if the specified collection is null | ### removeAllElements Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void removeAllElements () ``` Removes all components from this vector and sets its size to zero. This method is identical in functionality to the `https://developer.android.com/reference/java/util/Vector#clear()` method (which is part of the `https://developer.android.com/reference/java/util/List` interface).
### removeElement Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean removeElement (Object obj) ``` Removes the first (lowest-indexed) occurrence of the argument from this vector. If the object is found in this vector, each component in the vector with an index greater or equal to the object's index is shifted downward to have an index one smaller than the value it had previously. This method is identical in functionality to the `https://developer.android.com/reference/java/util/Vector#remove(java.lang.Object)` method (which is part of the `https://developer.android.com/reference/java/util/List` interface).
| Parameters || |---|---| | `obj` | `Object`: the component to be removed
| | Returns || |---|---| | `boolean` | `true` if the argument was a component of this vector; `false` otherwise.
| ### removeElementAt Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void removeElementAt (int index) ``` Deletes the component at the specified index. Each component in this vector with an index greater or equal to the specified `index` is shifted downward to have an index one smaller than the value it had previously. The size of this vector is decreased by `1`. The index must be a value greater than or equal to `0` and less than the current size of the vector. This method is identical in functionality to the `https://developer.android.com/reference/java/util/Vector#remove(int)` method (which is part of the `https://developer.android.com/reference/java/util/List` interface). Note that the `remove` method returns the old value that was stored at the specified position.
| Parameters || |---|---| | `index` | `int`: the index of the object to remove
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayIndexOutOfBoundsException` | if the index is out of range (`index < 0 || index >= size()`) | ### removeIf Added in [API level 24](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean removeIf (Predicate filter) ``` Removes all of the elements of this collection that satisfy the given predicate (optional operation). Errors or runtime exceptions thrown during iteration or by the predicate are relayed to the caller.
| Parameters || |---|---| | `filter` | `Predicate`: a predicate which returns `true` for elements to be removed
| | Returns || |---|---| | `boolean` | `true` if any elements were removed
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/NullPointerException` | | ### replaceAll Added in [API level 24](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void replaceAll (UnaryOperator operator) ``` Replaces each element of this list with the result of applying the operator to that element (optional operation). Errors or runtime exceptions thrown by the operator are relayed to the caller.
| Parameters || |---|---| | `operator` | `UnaryOperator`: the operator to apply to each element
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/NullPointerException` | | ### retainAll Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public boolean retainAll (Collection c) ``` Retains only the elements in this Vector that are contained in the specified Collection. In other words, removes from this Vector all of its elements that are not contained in the specified Collection.
| Parameters || |---|---| | `c` | `Collection`: a collection of elements to be retained in this Vector (all other elements are removed)
| | Returns || |---|---| | `boolean` | true if this Vector changed as a result of the call
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ClassCastException` | if the types of one or more elements in this vector are incompatible with the specified collection ([optional](https://developer.android.com/reference/java/util/Collection#optional-restrictions)) | | `https://developer.android.com/reference/java/lang/NullPointerException` | if this vector contains one or more null elements and the specified collection does not support null elements ([optional](https://developer.android.com/reference/java/util/Collection#optional-restrictions)), or if the specified collection is null | ### set Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public E set (int index, E element) ``` Replaces the element at the specified position in this Vector with the specified element.
| Parameters || |---|---| | `index` | `int`: index of the element to replace
| | `element` | `E`: element to be stored at the specified position
| | Returns || |---|---| | `E` | the element previously at the specified position
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayIndexOutOfBoundsException` | if the index is out of range (`index < 0 || index >= size()`) | ### setElementAt Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void setElementAt (E obj, int index) ``` Sets the component at the specified `index` of this vector to be the specified object. The previous component at that position is discarded. The index must be a value greater than or equal to `0` and less than the current size of the vector. This method is identical in functionality to the `https://developer.android.com/reference/java/util/Vector#set(int,%20E)` method (which is part of the `https://developer.android.com/reference/java/util/List` interface). Note that the `set` method reverses the order of the parameters, to more closely match array usage. Note also that the `set` method returns the old value that was stored at the specified position.
| Parameters || |---|---| | `obj` | `E`: what the component is to be set to
| | `index` | `int`: the specified index
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayIndexOutOfBoundsException` | if the index is out of range (`index < 0 || index >= size()`) | ### setSize Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void setSize (int newSize) ``` Sets the size of this vector. If the new size is greater than the current size, new `null` items are added to the end of the vector. If the new size is less than the current size, all components at index `newSize` and greater are discarded.
| Parameters || |---|---| | `newSize` | `int`: the new size of this vector
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayIndexOutOfBoundsException` | if the new size is negative | ### size Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public int size () ``` Returns the number of components in this vector.
| Returns || |---|---| | `int` | the number of components in this vector
| ### sort Added in [API level 24](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void sort (Comparator c) ``` Sorts this list according to the order induced by the specified `https://developer.android.com/reference/java/util/Comparator` (optional operation). The sort is *stable*: this method must not reorder equal elements. All elements in this list must be *mutually comparable* using the specified comparator (that is, `c.compare(e1, e2)` must not throw a `ClassCastException` for any elements `e1` and `e2` in the list). If the specified comparator is `null` then all elements in this list must implement the `https://developer.android.com/reference/java/lang/Comparable` interface and the elements' [natural ordering](https://developer.android.com/reference/java/lang/Comparable) should be used. This list must be modifiable, but need not be resizable. For apps running on and targeting Android versions greater than Nougat (API level `> 25`), `https://developer.android.com/reference/java/util/Collections#sort(java.util.List)` delegates to this method. Such apps must not call `https://developer.android.com/reference/java/util/Collections#sort(java.util.List)` from this method. Instead, prefer not overriding this method at all. If you must override it, consider this implementation: ``` @Override public void sort(Comparator c) { Object[] elements = toArray(); Arrays.sort(elements, c); ListIterator iterator = (ListIterator) listIterator(); for (Object element : elements) { iterator.next(); iterator.set((E) element); } } ```

| Parameters || |---|---| | `c` | `Comparator`: the `Comparator` used to compare list elements. A `null` value indicates that the elements' [natural ordering](https://developer.android.com/reference/java/lang/Comparable) should be used
| ### spliterator Added in [API level 24](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public Spliterator spliterator () ``` Creates a *[late-binding](https://developer.android.com/reference/java/util/Spliterator#binding)* and *fail-fast* `https://developer.android.com/reference/java/util/Spliterator` over the elements in this list. The `Spliterator` reports `https://developer.android.com/reference/java/util/Spliterator#SIZED`, `https://developer.android.com/reference/java/util/Spliterator#SUBSIZED`, and `https://developer.android.com/reference/java/util/Spliterator#ORDERED`. Overriding implementations should document the reporting of additional characteristic values.
| Returns || |---|---| | `https://developer.android.com/reference/java/util/Spliterator` | a `Spliterator` over the elements in this list
| ### subList Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public List subList (int fromIndex, int toIndex) ``` Returns a view of the portion of this List between 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 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 operating on 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 the List, or otherwise perturb it in such a fashion that iterations in progress may yield incorrect results.)
| Parameters || |---|---| | `fromIndex` | `int`: low endpoint (inclusive) of the subList
| | `toIndex` | `int`: high endpoint (exclusive) of the subList
| | Returns || |---|---| | `https://developer.android.com/reference/java/util/List` | a view of the specified range within this List
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/IllegalArgumentException` | if the endpoint indices are out of order `(fromIndex > toIndex)` | | `https://developer.android.com/reference/java/lang/IndexOutOfBoundsException` | if an endpoint index value is out of range `(fromIndex < 0 || toIndex > size)` | ### toArray Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public Object[] toArray () ``` Returns an array containing all of the elements in this Vector in the correct order.
| Returns || |---|---| | `https://developer.android.com/reference/java/lang/Object` | an array, whose [runtime component type](https://developer.android.com/reference/java/lang/Class#getComponentType()) is `Object`, containing all of the elements in this collection
| ### toArray Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public T[] toArray (T[] a) ``` Returns an array containing all of the elements in this Vector in the correct order; the runtime type of the returned array is that of the specified array. If the Vector 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 Vector. If the Vector fits in the specified array with room to spare (i.e., the array has more elements than the Vector), the element in the array immediately following the end of the Vector is set to null. (This is useful in determining the length of the Vector *only* if the caller knows that the Vector does not contain any null elements.)
| Parameters || |---|---| | `a` | `T`: the array into which the elements of the Vector are to be stored, if it is big enough; otherwise, a new array of the same runtime type is allocated for this purpose.
| | Returns || |---|---| | `T[]` | an array containing the elements of the Vector
| | Throws || |---|---| | `https://developer.android.com/reference/java/lang/ArrayStoreException` | if the runtime type of a, ``, is not a supertype of the runtime type, ``, of every element in this Vector | | `https://developer.android.com/reference/java/lang/NullPointerException` | if the given array is null | ### toString Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public String toString () ``` Returns a string representation of this Vector, containing the String representation of each element.
| Returns || |---|---| | `https://developer.android.com/reference/java/lang/String` | a string representation of this collection
| ### trimToSize Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` public void trimToSize () ``` Trims the capacity of this vector to be the vector's current size. If the capacity of this vector is larger than its current size, then the capacity is changed to equal the size by replacing its internal data array, kept in the field `elementData`, with a smaller one. An application can use this operation to minimize the storage of a vector.
## Protected methods ### removeRange Added in [API level 1](https://developer.android.com/guide/topics/manifest/uses-sdk-element#ApiLevels) ``` protected void removeRange (int fromIndex, int toIndex) ``` Removes from this list all of the elements whose index is between `fromIndex`, inclusive, and `toIndex`, exclusive. Shifts any succeeding elements to the left (reduces their index). This call shortens the list by `(toIndex - fromIndex)` elements. (If `toIndex==fromIndex`, this operation has no effect.)
| Parameters || |---|---| | `fromIndex` | `int`: index of first element to be removed
| | `toIndex` | `int`: index after last element to be removed
|