This class
implements an ordered collectionessentially an arrayof
objects that can grow or shrink as necessary. In Java 1.2,
Vector has been modified to implement the
List interface. Unless the
synchronized methods of the
Vector class are actually needed,
ArrayList is preferred in Java 1.2 and later. In
Java 5.0 this class has been made generic. The type variable
E represents the type of the elements of
the vector.
Vector is useful when you need to keep track of a
number of objects, but do not know in advance how many there will be.
Use setElementAt( ) to set the object at a given
index of a Vector. Use elementAt(
) to retrieve the object stored at a specified index. Call
add( ) to append an object to the end of the
Vector or to insert an object at any specified
position. Use removeElementAt( ) to delete the
element at a specified index or removeElement( )
to remove a specified object from the vector. size(
) returns the number of objects currently in the
Vector. elements( ) returns an
Enumeration that allows you to iterate through
those objects. capacity( ) is not the same as
size( ); it returns the maximum number of objects
a Vector can hold before its internal storage must
be resized. Vector automatically resizes its
internal storage for you, but if you know in advance how many objects
a Vector will contain, you can increase its
efficiency by pre-allocating this many elements with
ensureCapacity( ).
public class Vector<E> extends AbstractList<E> implements List<E>,
RandomAccess, Cloneable, Serializable {
// Public Constructors
public Vector( );
1.2 public Vector(Collection<? extends E> c);
public Vector(int initialCapacity);
public Vector(int initialCapacity, int capacityIncrement);
// Public Instance Methods
public void addElement(E obj); synchronized
public int capacity( ); synchronized
public boolean contains(Object elem); Implements:List
public void copyInto(Object[ ] anArray); synchronized
public E elementAt(int index); synchronized
public Enumeration<E> elements( );
public void ensureCapacity(int minCapacity); synchronized
public E firstElement( ); synchronized
public int indexOf(Object elem); Implements:List
public int indexOf(Object elem, int index); synchronized
public void insertElementAt(E obj, int index); synchronized
public boolean isEmpty( ); Implements:List synchronized default:true
public E lastElement( ); synchronized
public int lastIndexOf(Object elem); Implements:List synchronized
public int lastIndexOf(Object elem, int index); synchronized
public void removeAllElements( ); synchronized
public boolean removeElement(Object obj); synchronized
public void removeElementAt(int index); synchronized
public void setElementAt(E obj, int index); synchronized
public void setSize(int newSize); synchronized
public int size( ); Implements:List synchronized
public void trimToSize( ); synchronized
// Methods Implementing List
1.2 public boolean add(E o); synchronized
1.2 public void add(int index, E element);
1.2 public boolean addAll(Collection<? extends E> c); synchronized
1.2 public boolean addAll(int index, Collection<? extends E> c); synchronized
1.2 public void clear( );
public boolean contains(Object elem);
1.2 public boolean containsAll(Collection<?> c); synchronized
1.2 public boolean equals(Object o); synchronized
1.2 public E get(int index); synchronized
1.2 public int hashCode( ); synchronized
public int indexOf(Object elem);
public boolean isEmpty( ); synchronized default:true
public int lastIndexOf(Object elem); synchronized
1.2 public boolean remove(Object o);
1.2 public E remove(int index); synchronized
1.2 public boolean removeAll(Collection<?> c); synchronized
1.2 public boolean retainAll(Collection<?> c); synchronized
1.2 public E set(int index, E element); synchronized
public int size( ); synchronized
1.2 public List<E> subList(int fromIndex, int toIndex); synchronized
1.2 public Object[ ] toArray( ); synchronized
1.2 public <T> T[ ] toArray(T[ ] a); synchronized
// Protected Methods Overriding AbstractList
1.2 protected void removeRange(int fromIndex, int toIndex); synchronized
// Public Methods Overriding AbstractCollection
public String toString( ); synchronized
// Public Methods Overriding Object
public Object clone( ); synchronized
// Protected Instance Fields
protected int capacityIncrement;
protected int elementCount;
protected Object[ ] elementData;
}
