Storage Capacity : Vector « Collections « Java Tutorial

1. Java Tutorial
2. Collections
3. Vector

1. Capacity is the number of elements a vector can hold before resizing its internal data structures.
2. For performance reasons, it's best to reduce the number of times the internal structure has to resize.
3. If the capacity is too large, memory goes to waste.
4. To find out the current capacity of a vector: the capacity() method:

import java.util.Vector;

public class MainClass {
  public static void main(String args[]) {
    Vector v = new Vector(5);
    for (int i = 0; i < 10; i++) {
      v.add(0,i);
    }
    System.out.println(v);
    System.out.println(v.size());  

    for (int i = 0; i < 10; i++) {
      v.add(0,i);
    }
    
    System.out.println(v);
    System.out.println(v.size());
  }
}

[9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
10
[9, 8, 7, 6, 5, 4, 3, 2, 1, 0, 9, 8, 7, 6, 5, 4, 3, 2, 1, 0]
20