Vector

A Vector in Java is a legacy class that belongs to the java.util package and is similar to an ArrayList. It represents a dynamic array that can grow or shrink in size as elements are added or removed. Vector is synchronized, meaning it is thread-safe, which ensures that multiple threads can safely access and modify a Vector instance concurrently without causing data corruption.

import java.util.Vector;
// Syntax for creating a Vector
Vector<Type> vectorName = new Vector<>();Code language: JavaScript (javascript)

Methods:

1. Adding Elements
   • add(element): Appends the specified element to the end of the vector.
   • add(index, element): Inserts the specified element at the specified position in the vector.
2. Accessing Elements
   • get(index): Returns the element at the specified index in the vector.
   • firstElement(): Returns the first element of the vector.
   • lastElement(): Returns the last element of the vector.
3. Removing Elements
   • remove(index): Removes the element at the specified index from the vector.
   • removeElement(element): Removes the first occurrence of the specified element from the vector.
   • removeAllElements(): Removes all elements from the vector.
4. Size and Capacity
   • size(): Returns the number of elements currently in the vector.
   • capacity(): Returns the current capacity of the vector.
5. Other Operations
   • contains(element): Checks if the vector contains the specified element.
   • clear(): Removes all elements from the vector.
   • toArray(): Converts the vector to an array.

import java.util.Vector;
public class StudentVectorExample {
    public static void main(String[] args) {
        // Creating a Vector to store student names
        Vector<String> studentVector = new Vector<>();

        // Adding students to the Vector
        studentVector.add("Paani");
        studentVector.add("Mahesh");
        studentVector.add("Datta");
        studentVector.add("Ganesh");
        studentVector.add("Harsha");

        // Displaying the names of students
        System.out.println("List of students:");
        for (String student : studentVector) {
            System.out.println(student);
        }

        // Adding a new student at index 2
        studentVector.add(2, "NewStudent");

        // Displaying the updated list
        System.out.println("\nUpdated list of students:");
        for (String student : studentVector) {
            System.out.println(student);
        }

        // Removing a student at index 3
        studentVector.remove(3);

        // Displaying the final list
        System.out.println("\nFinal list of students:");
        for (String student : studentVector) {
            System.out.println(student);
        }
    }
}

D:\>javac StudentVectorExample.java

D:\>java StudentVectorExample
List of students:
Paani
Mahesh
Datta
Ganesh
Harsha

Updated list of students:
Paani
Mahesh
NewStudent
Datta
Ganesh
Harsha

Final list of students:
Paani
Mahesh
NewStudent
Ganesh
HarshaCode language: PHP (php)