21.11

java.util.Vector

THE PACKAGE JAVA.UTIL

21.11.17

public final void removeAllElements()

All elements are removed from this

Vector

, making it empty.

21.11.18

public final boolean isEmpty()

The result is

true

 if and only if this

Vector

 is empty, that is, its size is zero.

21.11.19

public final int size()

The size of this

Vector

 (the number of items it currently contains) is returned.

21.11.20

public final void setSize(int newSize)

The size of this

Vector

 is changed to

newSize

. If the new size is smaller than the

old size, then items are removed from the end and discarded. If the new size is

larger than the old size, then the new items are set to

null

.

21.11.21

public final int capacity()

The current capacity of this

Vector

 (the length of its internal data array, kept in

the field

elementData

) is returned.

21.11.22

public final void ensureCapacity(int minCapacity)

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

( 21.11.1), with a larger one. The size of the new data array will be the old size

plus

capacityIncrement

 ( 21.11.3), unless the value of

capacityIncrement

 is

nonpositive, 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

.

21.11.23

public final void trimToSize()

If the capacity of this

Vector

 is larger than its current

size

 ( 21.11.19), then the

capacity is changed to equal the size by replacing its internal data array, kept in

the field

elementData

, with a smaller one.

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