java.util
Class Vector<E>
java.lang.Objectjava.util.AbstractCollection<E>
java.util.AbstractList<E>
java.util.Vector<E>
- All Implemented Interfaces:
- Serializable, Cloneable, Iterable<E>, Collection<E>, List<E>, RandomAccess
- Direct Known Subclasses:
- Stack
public class Vector<E>
- extends AbstractList<E>
- implements List<E>, RandomAccess, Cloneable, Serializable
- extends AbstractList<E>
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 Vector's iterator and listIterator 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 remove or add methods, the Iterator will throw a 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 Enumerations returned by Vector's elements method are not fail-fast.
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 List interface, making it a member of the
Java
Collections Framework. Unlike the new collection
implementations, Vector is synchronized.
- Since:
- JDK1.0
- See Also:
Collection,List,ArrayList,LinkedList, Serialized Form
| Field Summary | |
|---|---|
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 this Vector object. |
protected Object[] |
elementData
The array buffer into which the components of the vector are stored. |
| Fields inherited from class java.util.AbstractList |
|---|
modCount |
| Constructor Summary | |
|---|---|
Vector()
Constructs an empty vector so that its internal data array has size 10 and its standard capacity increment is
zero. |
|
Vector(Collection<? extends E> c)
Constructs a vector containing the elements of the specified collection, in the order they are returned by the collection's iterator. |
|
Vector(int initialCapacity)
Constructs an empty vector with the specified initial capacity and with its capacity increment equal to zero. |
|
Vector(int initialCapacity,
int capacityIncrement)
Constructs an empty vector with the specified initial capacity and capacity increment. |
|
| Method Summary | ||
|---|---|---|
boolean |
add(E e)
Appends the specified element to the end of this Vector. |
|
void |
add(int index,
E element)
Inserts the specified element at the specified position in this Vector. |
|
boolean |
addAll(Collection<? extends E> 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. |
|
boolean |
addAll(int index,
Collection<? extends E> c)
Inserts all of the elements in the specified Collection into this Vector at the specified position. |
|
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. |
|
void |
clear()
Removes all of the elements from this Vector. |
|
Object |
clone()
Returns a clone of this vector. |
|
boolean |
contains(Object o)
Returns true if this vector contains the specified element. |
|
boolean |
containsAll(Collection<?> c)
Returns true if this Vector contains all of the elements in the specified Collection. |
|
void |
copyInto(Object[] anArray)
Copies the components of this vector into the specified array. |
|
E |
elementAt(int index)
Returns the component at the specified index. |
|
Enumeration<E> |
elements()
Returns an enumeration of the components of this vector. |
|
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. |
|
boolean |
equals(Object o)
Compares the specified Object with this Vector for equality. |
|
E |
firstElement()
Returns the first component (the item at index 0) of
this vector. |
|
E |
get(int index)
Returns the element at the specified position in this Vector. |
|
int |
hashCode()
Returns the hash code value for this Vector. |
|
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. |
|
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. |
|
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. |
|
E |
lastElement()
Returns the last component of the vector. |
|
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. |
|
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. |
|
E |
remove(int index)
Removes the element at the specified position in this Vector. |
|
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. |
|
boolean |
removeAll(Collection<?> c)
Removes from this Vector all of its elements that are contained in the specified Collection. |
|
void |
removeAllElements()
Removes all components from this vector and sets its size to zero. |
|
boolean |
removeElement(Object obj)
Removes the first (lowest-indexed) occurrence of the argument from this vector. |
|
void |
removeElementAt(int index)
Deletes the component at the specified index. |
|
protected void |
removeRange(int fromIndex,
int toIndex)
Removes from this List all of the elements whose index is between fromIndex, inclusive and toIndex, exclusive. |
|
boolean |
retainAll(Collection<?> c)
Retains only the elements in this Vector that are contained in the specified Collection. |
|
E |
set(int index,
E element)
Replaces the element at the specified position in this Vector with the specified element. |
|
void |
setElementAt(E obj,
int index)
Sets the component at the specified index of this
vector to be the specified object. |
|
void |
setSize(int newSize)
Sets the size of this vector. |
|
int |
size()
Returns the number of components in this vector. |
|
List<E> |
subList(int fromIndex,
int toIndex)
Returns a view of the portion of this List between fromIndex, inclusive, and toIndex, exclusive. |
|
Object[] |
toArray()
Returns an array containing all of the elements in this Vector in the correct order. |
|
|
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. |
|
String |
toString()
Returns a string representation of this Vector, containing the String representation of each element. |
|
void |
trimToSize()
Trims the capacity of this vector to be the vector's current size. |
|
| Methods inherited from class java.util.AbstractList |
|---|
iterator, listIterator, listIterator |
| Methods inherited from class java.lang.Object |
|---|
finalize, getClass, notify, notifyAll, wait, wait, wait |
| Methods inherited from interface java.util.List |
|---|
iterator, listIterator, listIterator |
| Field Detail |
|---|
elementData
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.
elementCount
protected int elementCount
- The number of valid components in this
Vectorobject. ComponentselementData[0]throughelementData[elementCount-1]are the actual items.
capacityIncrement
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.
| Constructor Detail |
|---|
Vector
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 vectorcapacityIncrement- the amount by which the capacity is increased when the vector overflows- Throws:
IllegalArgumentException- if the specified initial capacity is negative
Vector
public Vector(int initialCapacity)
- Constructs an empty vector with the specified initial capacity and
with its capacity increment equal to zero.
- Parameters:
initialCapacity- the initial capacity of the vector- Throws:
IllegalArgumentException- if the specified initial capacity is negative
Vector
public Vector()
- Constructs an empty vector so that its internal data array
has size
10and its standard capacity increment is zero.
Vector
public Vector(Collection<? extends E> c)
- Constructs a vector containing the elements of the specified
collection, in the order they are returned by the collection's
iterator.
- Parameters:
c- the collection whose elements are to be placed into this vector- Throws:
NullPointerException- if the specified collection is null- Since:
- 1.2
| Method Detail |
|---|
copyInto
public void copyInto(Object[] anArray)
- Copies the components of this vector into the specified array.
The item at index
kin this vector is copied into componentkofanArray.- Parameters:
anArray- the array into which the components get copied- Throws:
NullPointerException- if the given array is nullIndexOutOfBoundsException- if the specified array is not large enough to hold all the components of this vectorArrayStoreException- if a component of this vector is not of a runtime type that can be stored in the specified array- See Also:
toArray(Object[])
trimToSize
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.
ensureCapacity
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 fieldelementData, with a larger one. The size of the new data array will be the old size pluscapacityIncrement, unless the value ofcapacityIncrementis 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 thanminCapacity, then the new capacity will beminCapacity.- Parameters:
minCapacity- the desired minimum capacity
setSize
public void setSize(int newSize)
- Sets the size of this vector. If the new size is greater than the
current size, new
nullitems are added to the end of the vector. If the new size is less than the current size, all components at indexnewSizeand greater are discarded.- Parameters:
newSize- the new size of this vector- Throws:
ArrayIndexOutOfBoundsException- if the new size is negative
capacity
public int capacity()
- Returns the current capacity of this vector.
- Returns:
- the current capacity (the length of its internal
data array, kept in the field
elementDataof this vector)
size
public int size()
- Returns the number of components in this vector.
- Specified by:
sizein interfaceCollection<E>- Specified by:
sizein interfaceList<E>- Specified by:
sizein classAbstractCollection<E>
- Returns:
- the number of components in this vector
isEmpty
public boolean isEmpty()
- Tests if this vector has no components.
- Specified by:
isEmptyin interfaceCollection<E>- Specified by:
isEmptyin interfaceList<E>- Overrides:
isEmptyin classAbstractCollection<E>
- Returns:
trueif and only if this vector has no components, that is, its size is zero;falseotherwise.
elements
public Enumeration<E> elements()
- Returns an enumeration of the components of this vector. The
returned
Enumerationobject will generate all items in this vector. The first item generated is the item at index0, then the item at index1, and so on.- Returns:
- an enumeration of the components of this vector
- See Also:
Iterator
contains
public boolean contains(Object o)
- Returns
trueif this vector contains the specified element. More formally, returnstrueif and only if this vector contains at least one elementesuch that (o==null ? e==null : o.equals(e)).- Specified by:
containsin interfaceCollection<E>- Specified by:
containsin interfaceList<E>- Overrides:
containsin classAbstractCollection<E>
- Parameters:
o- element whose presence in this vector is to be tested- Returns:
trueif this vector contains the specified element
indexOf
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
isuch that (o==null ? get(i)==null : o.equals(get(i))), or -1 if there is no such index.- Parameters:
o- element to search for- Returns:
- the index of the first occurrence of the specified element in this vector, or -1 if this vector does not contain the element
indexOf
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 indexisuch that (i >= index && (o==null ? get(i)==null : o.equals(get(i)))), or -1 if there is no such index.- Parameters:
o- element to search forindex- index to start searching from- Returns:
- the index of the first occurrence of the element in
this vector at position
indexor later in the vector;-1if the element is not found. - Throws:
IndexOutOfBoundsException- if the specified index is negative- See Also:
Object.equals(Object)
lastIndexOf
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
isuch that (o==null ? get(i)==null : o.equals(get(i))), or -1 if there is no such index.- Specified by:
lastIndexOfin interfaceList<E>- Overrides:
lastIndexOfin classAbstractList<E>
- Parameters:
o- element to search for- Returns:
- the index of the last occurrence of the specified element in this vector, or -1 if this vector does not contain the element
lastIndexOf
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 indexisuch that (i <= index && (o==null ? get(i)==null : o.equals(get(i)))), or -1 if there is no such index.- Parameters:
o- element to search forindex- index to start searching backwards from- Returns:
- the index of the last occurrence of the element at position
less than or equal to
indexin this vector; -1 if the element is not found. - Throws:
IndexOutOfBoundsException- if the specified index is greater than or equal to the current size of this vector
elementAt
public E elementAt(int index)
- Returns the component at the specified index.
This method is identical in functionality to the
get(int)method (which is part of theListinterface).- Parameters:
index- an index into this vector- Returns:
- the component at the specified index
- Throws:
ArrayIndexOutOfBoundsException- if the index is out of range (index < 0 || index >= size())
firstElement
public E firstElement()
- Returns the first component (the item at index
0) of this vector.- Returns:
- the first component of this vector
- Throws:
NoSuchElementException- if this vector has no components
lastElement
public 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
setElementAt
public void setElementAt(E obj, int index)
- Sets the component at the specified
indexof 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
0and less than the current size of the vector.This method is identical in functionality to the
set(int, E)method (which is part of theListinterface). Note that thesetmethod reverses the order of the parameters, to more closely match array usage. Note also that thesetmethod returns the old value that was stored at the specified position.- Parameters:
obj- what the component is to be set toindex- the specified index- Throws:
ArrayIndexOutOfBoundsException- if the index is out of range (index < 0 || index >= size())
removeElementAt
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
indexis shifted downward to have an index one smaller than the value it had previously. The size of this vector is decreased by1.The index must be a value greater than or equal to
0and less than the current size of the vector.This method is identical in functionality to the
remove(int)method (which is part of theListinterface). Note that theremovemethod returns the old value that was stored at the specified position.- Parameters:
index- the index of the object to remove- Throws:
ArrayIndexOutOfBoundsException- if the index is out of range (index < 0 || index >= size())
insertElementAt
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 specifiedindexis 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
0and 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
add(int, E)method (which is part of theListinterface). Note that theaddmethod reverses the order of the parameters, to more closely match array usage.- Parameters:
obj- the component to insertindex- where to insert the new component- Throws:
ArrayIndexOutOfBoundsException- if the index is out of range (index < 0 || index > size())
addElement
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
add(E)method (which is part of theListinterface).- Parameters:
obj- the component to be added
removeElement
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
remove(Object)method (which is part of theListinterface).- Parameters:
obj- the component to be removed- Returns:
trueif the argument was a component of this vector;falseotherwise.
removeAllElements
public void removeAllElements()
- Removes all components from this vector and sets its size to zero.
This method is identical in functionality to the
clear()method (which is part of theListinterface).
clone
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
Vectorobject.- Returns:
- a clone of this vector
- See Also:
Cloneable
toArray
public Object[] toArray()
- Returns an array containing all of the elements in this Vector
in the correct order.
- Specified by:
toArrayin interfaceCollection<E>- Specified by:
toArrayin interfaceList<E>- Overrides:
toArrayin classAbstractCollection<E>
- Returns:
- an array containing all of the elements in this collection
- Since:
- 1.2
- See Also:
Arrays.asList(Object[])
toArray
public <T> 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.)
- Specified by:
toArrayin interfaceCollection<E>- Specified by:
toArrayin interfaceList<E>- Overrides:
toArrayin classAbstractCollection<E>
- Parameters:
a- 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:
- an array containing the elements of the Vector
- Throws:
ArrayStoreException- if the runtime type of a is not a supertype of the runtime type of every element in this VectorNullPointerException- if the given array is null- Since:
- 1.2
get
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())- Since:
- 1.2
set
public E set(int index, E element)
- Replaces the element at the specified position in this Vector with the
specified element.
- Parameters:
index- index of the element to replaceelement- element to be stored at the specified position- Returns:
- the element previously at the specified position
- Throws:
ArrayIndexOutOfBoundsException- if the index is out of range (index < 0 || index >= size())- Since:
- 1.2
add
public boolean add(E e)
- Appends the specified element to the end of this Vector.
- Specified by:
addin interfaceCollection<E>- Specified by:
addin interfaceList<E>- Overrides:
addin classAbstractList<E>
- Parameters:
e- element to be appended to this Vector- Returns:
true(as specified byCollection.add(E))- Since:
- 1.2
remove
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
(o==null ? get(i)==null : o.equals(get(i)))(if such an element exists).- Specified by:
removein interfaceCollection<E>- Specified by:
removein interfaceList<E>- Overrides:
removein classAbstractCollection<E>
- Parameters:
o- element to be removed from this Vector, if present- Returns:
- true if the Vector contained the specified element
- Since:
- 1.2
add
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- index at which the specified element is to be insertedelement- element to be inserted- Throws:
ArrayIndexOutOfBoundsException- if the index is out of range (index < 0 || index > size())- Since:
- 1.2
remove
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- the index of the element to be removed- Returns:
- element that was removed
- Throws:
ArrayIndexOutOfBoundsException- if the index is out of range (index < 0 || index >= size())- Since:
- 1.2
clear
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).
- Specified by:
clearin interfaceCollection<E>- Specified by:
clearin interfaceList<E>- Overrides:
clearin classAbstractList<E>
- Since:
- 1.2
containsAll
public boolean containsAll(Collection<?> c)
- Returns true if this Vector contains all of the elements in the
specified Collection.
- Specified by:
containsAllin interfaceCollection<E>- Specified by:
containsAllin interfaceList<E>- Overrides:
containsAllin classAbstractCollection<E>
- Parameters:
c- a collection whose elements will be tested for containment in this Vector- Returns:
- true if this Vector contains all of the elements in the specified collection
- Throws:
NullPointerException- if the specified collection is null- See Also:
AbstractCollection.contains(Object)
addAll
public boolean addAll(Collection<? extends E> 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.)
- Specified by:
addAllin interfaceCollection<E>- Specified by:
addAllin interfaceList<E>- Overrides:
addAllin classAbstractCollection<E>
- Parameters:
c- elements to be inserted into this Vector- Returns:
trueif this Vector changed as a result of the call- Throws:
NullPointerException- if the specified collection is null- Since:
- 1.2
- See Also:
AbstractCollection.add(Object)
removeAll
public boolean removeAll(Collection<?> c)
- Removes from this Vector all of its elements that are contained in the
specified Collection.
- Specified by:
removeAllin interfaceCollection<E>- Specified by:
removeAllin interfaceList<E>- Overrides:
removeAllin classAbstractCollection<E>
- Parameters:
c- a collection of elements to be removed from the Vector- Returns:
- true if this Vector changed as a result of the call
- Throws:
ClassCastException- if the types of one or more elements in this vector are incompatible with the specified collection (optional)NullPointerException- if this vector contains one or more null elements and the specified collection does not support null elements (optional), or if the specified collection is null- Since:
- 1.2
- See Also:
AbstractCollection.remove(Object),AbstractCollection.contains(Object)
retainAll
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.
- Specified by:
retainAllin interfaceCollection<E>- Specified by:
retainAllin interfaceList<E>- Overrides:
retainAllin classAbstractCollection<E>
- Parameters:
c- a collection of elements to be retained in this Vector (all other elements are removed)- Returns:
- true if this Vector changed as a result of the call
- Throws:
ClassCastException- if the types of one or more elements in this vector are incompatible with the specified collection (optional)NullPointerException- if this vector contains one or more null elements and the specified collection does not support null elements (optional), or if the specified collection is null- Since:
- 1.2
- See Also:
AbstractCollection.remove(Object),AbstractCollection.contains(Object)
addAll
public boolean addAll(int index,
Collection<? extends E> 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- index at which to insert the first element from the specified collectionc- elements to be inserted into this Vector- Returns:
trueif this Vector changed as a result of the call- Throws:
ArrayIndexOutOfBoundsException- if the index is out of range (index < 0 || index > size())NullPointerException- if the specified collection is null- Since:
- 1.2
equals
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
e1ande2are equal if(e1==null ? e2==null : e1.equals(e2)).) In other words, two Lists are defined to be equal if they contain the same elements in the same order.- Specified by:
equalsin interfaceCollection<E>- Specified by:
equalsin interfaceList<E>- Overrides:
equalsin classAbstractList<E>
- Parameters:
o- the Object to be compared for equality with this Vector- Returns:
- true if the specified Object is equal to this Vector
- See Also:
Object.hashCode(),Hashtable
hashCode
public int hashCode()
- Returns the hash code value for this Vector.
- Specified by:
hashCodein interfaceCollection<E>- Specified by:
hashCodein interfaceList<E>- Overrides:
hashCodein classAbstractList<E>
- Returns:
- the hash code value for this list
- See Also:
Object.equals(java.lang.Object),Hashtable
toString
public String toString()
- Returns a string representation of this Vector, containing
the String representation of each element.
- Overrides:
toStringin classAbstractCollection<E>
- Returns:
- a string representation of this collection
subList
public List<E> 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- low endpoint (inclusive) of the subListtoIndex- high endpoint (exclusive) of the subList- Returns:
- a view of the specified range within this List
- Throws:
IndexOutOfBoundsException- if an endpoint index value is out of range(fromIndex < 0 || toIndex > size)IllegalArgumentException- if the endpoint indices are out of order(fromIndex > toIndex)
removeRange
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 ArrayList by (toIndex - fromIndex) elements. (If
toIndex==fromIndex, this operation has no effect.)
- Overrides:
removeRangein classAbstractList<E>
- Parameters:
fromIndex- index of first element to be removedtoIndex- index after last element to be removed
