What is Vector in Java?

Vector is a legacy class that represents a dynamic array. This class existed before Collection framework and is modified after the introduction of Collection framework to make a compatible to the Collection framework.

Commonly used methods of Vector:

addElement () : It is used to add an element to a Vector.
```
public boolean addElement(Object element)
```
removeElement () : It is used to remove element from Vector.
```
public boolean remove(Object element)
```
capacity () : It returns the capacity of a Vector.
```
public int capacity()
```
ensureCapacity () : It is used to increase the capacity of a Vector.
```
public void ensureCapacity(int capacity)
```
elements () : It is used to obtain Enumeration for traversing the Vector elements.
```
public Enumeration elements()
```

Enumeration is legacy interface that is used by collection to facilitate traversing there objects in implementation independent manner.

Methods of Enumeration Interface:

hasMoreElements () : It is used to find out whether an element is collection or not.
```
public boolean hasMoreElements()
```
nextElement () : It is used to obtain reference of next element of an collection.
```
Public Object nextElement()
```

JbkEmployee.java

package com.javabykiran.vector;

public class JbkEmployee {
    String name;
    String job;
    int salary;
    public JbkEmployee(String name, String job, int salary) {
	super();
	this.name = name;
	this.job = job;
	this.salary = salary;
    }

    public void display() {
	System.out.println("Name -> " + name + " job -> " + job + " salary -> " + salary);
    }

    public boolean equals(Object o) {
        JbkEmployee e1 = (JbkEmployee) o;
	return this.name.equals(e1.name) && this.job.equals(e1.job) && this.salary == e1.salary;
    }
}

JbkVectorDemo.java

package com.javabykiran.vector;
import java.util.Enumeration;
import java.util.Vector;

public class JbkVectorDemo {
    public static void main(String[] args) {
	Vector v = new Vector<>();

	v.add(new JbkEmployee("JavaByKiran", "JavaTrainer", 15000));
	v.add(new JbkEmployee("JavaByKiran", "SeleniumTrainer", 15000));
	v.add(new JbkEmployee("JavaByKiran", "PythonTrainer", 15000));

	System.out.println("Number of Element in Vector : " + v.size());

	Enumeration en = v.elements();

	while (en.hasMoreElements()) {
            JbkEmployee e1 = (JbkEmployee) en.nextElement();
            System.out.println(e1.hashCode() + "\t");
            e1.display();
	}
	System.out.println("Following object is search in the vector");
	JbkEmployee e2 = new JbkEmployee("JavaByKiran", "JavaTrainer", 15000);
	System.out.println(e2.hashCode() + "\t");
	e2.display();
	System.out.println("Search result is :" + v.contains(e2));

	System.out.println("Removing following object in the vector");
	JbkEmployee e3 = new JbkEmployee("JavaByKiran", "SeleniumTrainer", 15000);
	System.out.println(e3.hashCode() + "\t");
	e3.display();
	System.out.println("Removing elements is :" + v.remove(e3));
	System.out.println("After removing number of Elements in vector :" + v.size());
    }
}


    Output:
     Number of Element in Vector : 3
     366712642	
     Name -> JavaByKiran job -> JavaTrainer salary -> 15000
     1829164700	
     Name -> JavaByKiran job -> SeleniumTrainer salary -> 15000
     2018699554	
     Name -> JavaByKiran job -> PythonTrainer salary -> 15000
     Following object is search in the vector
     1311053135	
     Name -> JavaByKiran job -> JavaTrainer salary -> 15000
     Search result is :true
     Removing following object in the vector
     118352462	
     Name -> JavaByKiran job -> SeleniumTrainer salary -> 15000
     Removing elements is :true
     After removing number of Elements in vector :2

What is Vector in Java?

Introduction to Java Vector

Enumeration Interface

Example of Vector