public class

Vector

extends AbstractList<E>
implements List<E> RandomAccess

java.lang.Object
↳	java.util.AbstractCollection<E>
	↳	java.util.AbstractList<E>
		↳	java.util.Vector<E>

Known Direct Subclasses

Stack<T>

Class Overview

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.

Note: To conserve space, the CLDC implementation is based on JDK 1.1.8, not JDK 1.3.

Summary

Fields
protected int	capacityIncrement	The amount by which the capacity of the vector is automatically incremented when its size becomes greater than its capacity.
protected int	elementCount	The number of valid components in the vector.
protected E[]	elementData	The array buffer into which the components of the vector are stored.

[Expand]

Inherited Fields

From class java.util.AbstractList

Public Constructors
	Vector(int initialCapacity, int capacityIncrement) Constructs an empty vector with the specified initial capacity and capacity increment.
	Vector(int initialCapacity) Constructs an empty vector with the specified initial capacity.
	Vector() Constructs an empty vector.

Public Methods
synchronized void	addElement(E obj) Adds the specified component to the end of this vector, increasing its size by one.
int	capacity() Returns the current capacity of this vector.
boolean	contains(Object elem) Tests if the specified object is a component in this vector.
synchronized void	copyInto(Object[] anArray) Copies the components of this vector into the specified array.
synchronized E	elementAt(int index) Returns the component at the specified index.
synchronized Enumeration<E>	elements() Returns an enumeration of the components of this vector.
synchronized 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.
synchronized E	firstElement() Returns the first component of this vector.
E	get(int index) Returns the element at the specified position in this Vector.
int	indexOf(Object elem) Searches for the first occurrence of the given argument, testing for equality using the `equals` method.
synchronized int	indexOf(Object elem, int index) Searches for the first occurrence of the given argument, beginning the search at `index`, and testing for equality using the `equals` method.
synchronized void	insertElementAt(E obj, int index) Inserts the specified object as a component in this vector at the specified `index`.
boolean	isEmpty() Tests if this vector has no components.
synchronized E	lastElement() Returns the last component of the vector.
int	lastIndexOf(Object elem) Returns the index of the last occurrence of the specified object in this vector.
synchronized int	lastIndexOf(Object elem, int index) Searches backwards for the specified object, starting from the specified index, and returns an index to it.
synchronized void	removeAllElements() Removes all components from this vector and sets its size to zero.
synchronized boolean	removeElement(Object obj) Removes the first occurrence of the argument from this vector.
synchronized void	removeElementAt(int index) Deletes the component at the specified index.
synchronized void	setElementAt(E obj, int index) Sets the component at the specified `index` of this vector to be the specified object.
synchronized void	setSize(int newSize) Sets the size of this vector.
int	size() Returns the number of components in this vector.
synchronized Object[]	toArray() Returns an array containing all of the elements in this Vector in the correct order.
synchronized String	toString() Returns a string representation of this vector.
synchronized void	trimToSize() Trims the capacity of this vector to be the vector's current size.

[Expand]

Inherited Methods

From class java.util.AbstractList

void	add(int location, E object) Inserts the specified object into this List at the specified location.
boolean	add(E object) Adds the specified object at the end of this List.
boolean	addAll(int location, Collection<? extends E> collection) Inserts the objects in the specified Collection at the specified location in this List.
void	clear() Removes all elements from this list, leaving it empty.
boolean	equals(Object object) Compares the specified object to this list and return true if they are equal.
abstract E	get(int location) Returns the element at the specified location in this list.
int	hashCode() Returns the hash code of this list.
int	indexOf(Object object) Searches this list for the specified object and returns the index of the first occurrence.
Iterator<E>	iterator() Returns an iterator on the elements of this list.
int	lastIndexOf(Object object) Searches this list for the specified object and returns the index of the last occurrence.
ListIterator<E>	listIterator(int location) Returns a list iterator on the elements of this list.
ListIterator<E>	listIterator() Returns a ListIterator on the elements of this list.
E	remove(int location) Removes the object at the specified location from this list.
void	removeRange(int start, int end) Removes the objects in the specified range from the start to the end index minus one.
E	set(int location, E object) Replaces the element at the specified location in this list with the specified object.
List<E>	subList(int start, int end) Returns a part of consecutive elements of this list as a view.
Object[]	toArray() Returns a new array containing all elements contained in this `ArrayList`.

From class java.util.AbstractCollection

boolean	add(E object) Attempts to add `object` to the contents of this `Collection` (optional).
boolean	addAll(Collection<? extends E> collection) Attempts to add all of the objects contained in `collection` to the contents of this `Collection` (optional).
void	clear() Removes all elements from this `Collection`, leaving it empty (optional).
boolean	contains(Object object) Tests whether this `Collection` contains the specified object.
boolean	containsAll(Collection<?> collection) Tests whether this `Collection` contains all objects contained in the specified `Collection`.
boolean	isEmpty() Returns if this `Collection` contains no elements.
abstract Iterator<E>	iterator() Returns an instance of `Iterator` that may be used to access the objects contained by this `Collection`.
boolean	remove(Object object) Removes one instance of the specified object from this `Collection` if one is contained (optional).
boolean	removeAll(Collection<?> collection) Removes all occurrences in this `Collection` of each object in the specified `Collection` (optional).
boolean	retainAll(Collection<?> collection) Removes all objects from this `Collection` that are not also found in the `Collection` passed (optional).
abstract int	size() Returns a count of how many objects this `Collection` contains.
Object[]	toArray() Returns a new array containing all elements contained in this `ArrayList`.
String	toString() Returns the string representation of this `Collection`.

From class java.lang.Object

boolean	equals(Object obj) Indicates whether some other object is "equal to" this one.
final Class<?>	getClass() Returns the runtime class of an object.
int	hashCode() Returns a hash code value for the object.
final void	notify() Wakes up a single thread that is waiting on this object's monitor.
final void	notifyAll() Wakes up all threads that are waiting on this object's monitor.
String	toString() Returns a string representation of the object.
final void	wait(long timeout, int nanos) Causes current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object, or some other thread interrupts the current thread, or a certain amount of real time has elapsed.
final void	wait(long timeout) Causes current thread to wait until either another thread invokes the `notify()` method or the `notifyAll()` method for this object, or a specified amount of time has elapsed.
final void	wait() Causes current thread to wait until another thread invokes the `notify()` method or the `notifyAll()` method for this object.

From interface java.lang.Iterable

From interface java.util.Collection

abstract boolean	add(E object) Attempts to add `object` to the contents of this `Collection` (optional).
abstract boolean	addAll(Collection<? extends E> collection) Attempts to add all of the objects contained in `Collection` to the contents of this `Collection` (optional).
abstract void	clear() Removes all elements from this `Collection`, leaving it empty (optional).
abstract boolean	contains(Object object) Tests whether this `Collection` contains the specified object.
abstract boolean	containsAll(Collection<?> collection) Tests whether this `Collection` contains all objects contained in the specified `Collection`.
abstract boolean	equals(Object object) Compares the argument to the receiver, and returns true if they represent the same object using a class specific comparison.
abstract int	hashCode() Returns an integer hash code for the receiver.
abstract boolean	isEmpty() Returns if this `Collection` contains no elements.
abstract Iterator<E>	iterator() Returns an instance of `Iterator` that may be used to access the objects contained by this `Collection`.
abstract boolean	remove(Object object) Removes one instance of the specified object from this `Collection` if one is contained (optional).
abstract boolean	removeAll(Collection<?> collection) Removes all occurrences in this `Collection` of each object in the specified `Collection` (optional).
abstract boolean	retainAll(Collection<?> collection) Removes all objects from this `Collection` that are not also found in the `Collection` passed (optional).
abstract int	size() Returns a count of how many objects this `Collection` contains.
abstract <T> T[]	toArray(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 Object[]	toArray() Returns an array containing all of the elements in this collection.

From interface java.util.List

abstract boolean	add(E object) Adds the specified object at the end of this `List`.
abstract void	add(int location, E object) Inserts the specified object into this `List` at the specified location.
abstract boolean	addAll(Collection<? extends E> collection) Adds the objects in the specified collection to the end of this `List`.
abstract boolean	addAll(int location, Collection<? extends E> collection) Inserts the objects in the specified collection at the specified location in this `List`.
abstract void	clear() Removes all elements from this `List`, leaving it empty.
abstract boolean	contains(Object object) Tests whether this `List` contains the specified object.
abstract boolean	containsAll(Collection<?> collection) Tests whether this `List` contains all objects contained in the specified collection.
abstract boolean	equals(Object object) Compares the given object with the `List`, and returns true if they represent the same object using a class specific comparison.
abstract E	get(int location) Returns the element at the specified location in this `List`.
abstract int	hashCode() Returns the hash code for this `List`.
abstract int	indexOf(Object object) Searches this `List` for the specified object and returns the index of the first occurrence.
abstract boolean	isEmpty() Returns whether this `List` contains no elements.
abstract Iterator<E>	iterator() Returns an iterator on the elements of this `List`.
abstract int	lastIndexOf(Object object) Searches this `List` for the specified object and returns the index of the last occurrence.
abstract ListIterator<E>	listIterator(int location) Returns a list iterator on the elements of this `List`.
abstract ListIterator<E>	listIterator() Returns a `List` iterator on the elements of this `List`.
abstract E	remove(int location) Removes the object at the specified location from this `List`.
abstract boolean	remove(Object object) Removes the first occurrence of the specified object from this `List`.
abstract boolean	removeAll(Collection<?> collection) Removes all occurrences in this `List` of each object in the specified collection.
abstract boolean	retainAll(Collection<?> collection) Removes all objects from this `List` that are not contained in the specified collection.
abstract E	set(int location, E object) Replaces the element at the specified location in this `List` with the specified object.
abstract int	size() Returns the number of elements in this `List`.
abstract List<E>	subList(int start, int end) Returns a `List` of the specified portion of this `List` from the given start index to the end index minus one.
abstract Object[]	toArray() Returns an array containing all of the elements in this list in proper sequence (from first to last element).
abstract <T> T[]	toArray(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.

Fields

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 0, the capacity of the vector is doubled each time it needs to grow.

protected int elementCount

The number of valid components in the vector.

protected E[] 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.

Public Constructors

public Vector (int initialCapacity, int capacityIncrement)

Constructs an empty vector with the specified initial capacity and capacity increment.

Parameters

initialCapacity	the initial capacity of the vector.
capacityIncrement	the amount by which the capacity is increased when the vector overflows.

Throws

IllegalArgumentException	if the specified initial capacity is negative

public Vector (int initialCapacity)

Constructs an empty vector with the specified initial capacity.

Parameters

initialCapacity	the initial capacity of the vector.

public Vector ()

Constructs an empty vector.

Public Methods

public synchronized 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.

Parameters

obj	the component to be added.

public int capacity ()

Returns the current capacity of this vector.

Returns

the current capacity of this vector.

public boolean contains (Object elem)

Tests if the specified object is a component in this vector.

Parameters

elem	an object.

Returns

true if the specified object is a component in this vector; false otherwise.

public synchronized void copyInto (Object[] anArray)

Copies the components of this vector into the specified array. The array must be big enough to hold all the objects in this vector.

Parameters

anArray	the array into which the components get copied.

public synchronized E elementAt (int index)

Returns the component at the specified index.

Parameters

index	an index into this vector.

Returns

the component at the specified index.

Throws

ArrayIndexOutOfBoundsException	if an invalid index was given.

public synchronized Enumeration<E> elements ()

Returns an enumeration of the components of this vector.

Returns

an enumeration of the components of this vector.

public synchronized 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.

Parameters

minCapacity	the desired minimum capacity.

public synchronized E firstElement ()

Returns the first component of this vector.

Returns

the first component of this vector.

Throws

NoSuchElementException	if this vector has no components.

public E get (int index)

Returns the element at the specified position in this Vector.

Parameters

index	index of the element to return

Returns

object at the specified index

Throws

ArrayIndexOutOfBoundsException	if the index is out of range (`index < 0 \|\| index >= size()`)

public int indexOf (Object elem)

Searches for the first occurrence of the given argument, testing for equality using the equals method.

Parameters

elem	an object.

Returns

the index of the first occurrence of the argument in this vector; returns -1 if the object is not found.

public synchronized int indexOf (Object elem, int index)

Searches for the first occurrence of the given argument, beginning the search at index, and testing for equality using the equals method.

Parameters

elem	an object.
index	the index to start searching from.

Returns

the index of the first occurrence of the object argument in this vector at position index or later in the vector; returns -1 if the object is not found.

public synchronized 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.

Parameters

obj	the component to insert.
index	where to insert the new component.

Throws

ArrayIndexOutOfBoundsException	if the index was invalid.

public boolean isEmpty ()

Tests if this vector has no components.

Returns

true if this vector has no components; false otherwise.

public synchronized E lastElement ()

Returns the last component of the vector.

Returns

the last component of the vector, i.e., the component at index size() - 1.

Throws

NoSuchElementException	if this vector is empty.

public int lastIndexOf (Object elem)

Returns the index of the last occurrence of the specified object in this vector.

Parameters

elem	the desired component.

Returns

the index of the last occurrence of the specified object in this vector; returns -1 if the object is not found.

public synchronized int lastIndexOf (Object elem, int index)

Searches backwards for the specified object, starting from the specified index, and returns an index to it.

Parameters

elem	the desired component.
index	the index to start searching from.

Returns

the index of the last occurrence of the specified object in this vector at position less than index in the vector; -1 if the object is not found.

Throws

IndexOutOfBoundsException	if `index` is greater than or equal to the current size of this vector.

public synchronized void removeAllElements ()

Removes all components from this vector and sets its size to zero.

public synchronized boolean removeElement (Object obj)

Removes the first 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.

Parameters

obj	the component to be removed.

Returns

true if the argument was a component of this vector; false otherwise.

public synchronized 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 index must be a value greater than or equal to 0 and less than the current size of the vector.

Parameters

index	the index of the object to remove.

Throws

ArrayIndexOutOfBoundsException	if the index was invalid.

public synchronized 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.

Parameters

obj	what the component is to be set to.
index	the specified index.

Throws

ArrayIndexOutOfBoundsException	if the index was invalid.

public synchronized 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	the new size of this vector.

public int size ()

Returns the number of components in this vector.

Returns

the number of components in this vector.

public synchronized Object[] toArray ()

Returns an array containing all of the elements in this Vector in the correct order.

Returns

an array of the elements from this ArrayList

public synchronized String toString ()

Returns a string representation of this vector.

Returns

a string representation of this vector.

public synchronized void trimToSize ()

Trims the capacity of this vector to be the vector's current size. An application can use this operation to minimize the storage of a vector.

Interfaces

Classes

Exceptions

Vector

Class Overview

Summary

Fields

protected int capacityIncrement

protected int elementCount

protected E[] elementData

Public Constructors

public Vector (int initialCapacity, int capacityIncrement)

Parameters

Throws

public Vector (int initialCapacity)

Parameters

public Vector ()

Public Methods

public synchronized void addElement (E obj)

Parameters

public int capacity ()

Returns

public boolean contains (Object elem)

Parameters

Returns

public synchronized void copyInto (Object[] anArray)

Parameters

public synchronized E elementAt (int index)

Parameters

Returns

Throws

public synchronized Enumeration<E> elements ()

Returns

See Also

public synchronized void ensureCapacity (int minCapacity)

Parameters

public synchronized E firstElement ()

Returns

Throws

public E get (int index)

Parameters

Returns

Throws

public int indexOf (Object elem)

Parameters

Returns

See Also

public synchronized int indexOf (Object elem, int index)

Parameters

Returns

See Also

public synchronized void insertElementAt (E obj, int index)

Parameters

Throws

See Also

public boolean isEmpty ()

Returns

public synchronized E lastElement ()

Returns

Throws

public int lastIndexOf (Object elem)

Parameters

Returns

public synchronized int lastIndexOf (Object elem, int index)

Parameters

Returns

Throws

public synchronized void removeAllElements ()

public synchronized boolean removeElement (Object obj)

Parameters

Returns

public synchronized void removeElementAt (int index)

Parameters

Throws

See Also

public synchronized void setElementAt (E obj, int index)

Parameters

Throws

See Also

public synchronized void setSize (int newSize)