Java Vector equals()

Java Vector [Java Vector] Java Vector

equals() Java Vector Vector AbstractList List equals() 

public boolean equals(Object o)

  • o Vector
    • Object
    • Java List

  • boolean
    • true List
    • false

1.

equals() Vector Vector equals() true

Vector<String> v1 = new Vector<>(Arrays.asList("A", "B", "C"));
Vector<String> v2 = new Vector<>(Arrays.asList("A", "B", "C"));

System.out.println(v1.equals(v2)); // true

2. List

Vector List equals() List ArrayListLinkedList

Vector<String> vector = new Vector<>(Arrays.asList(1, 2, 3));
ArrayList<Integer> arrayList = new ArrayList<>(Arrays.asList(1, 2, 3));

System.out.println(vector.equals(arrayList)); // true

3.

equals() false

Vector<String> v1 = new Vector<>(Arrays.asList("A", "B", "C"));
Vector<String> v2 = new Vector<>(Arrays.asList("C", "B", "A"));

System.out.println(v1.equals(v2)); // false

Vector equals() AbstractList

  2. List
  4. equals()

1. equals()

Vector equals() equals() equals()

2. null

Vector null equals() null

Vector<String> v1 = new Vector<>(Arrays.asList(null, "B"));
Vector<String> v2 = new Vector<>(Arrays.asList(null, "B"));

System.out.println(v1.equals(v2)); // true

3.

Vectorequals() O(n)

import java.util.Vector;
import java.util.Arrays;

public class VectorEqualsExample {
    public static void main(String[] args) {
        // Vector
        Vector<String> vector1 = new Vector<>(Arrays.asList("Java", "Python", "C++"));
        Vector<String> vector2 = new Vector<>(Arrays.asList("Java", "Python", "C++"));
        Vector<String> vector3 = new Vector<>(Arrays.asList("Python", "Java", "C++"));
       
        // vector1 vector2
        System.out.println("vector1 equals vector2: " + vector1.equals(vector2)); // true
       
        // vector1 vector3
        System.out.println("vector1 equals vector3: " + vector1.equals(vector3)); // false
       
        // ArrayList
        java.util.ArrayList<String> arrayList =
            new java.util.ArrayList<>(Arrays.asList("Java", "Python", "C++"));
        System.out.println("vector1 equals arrayList: " + vector1.equals(arrayList)); // true
    }
}

equals() vs ==

  • equals()
  • ==

Vector<String> v1 = new Vector<>();
Vector<String> v2 = new Vector<>();
Vector<String> v3 = v1;

System.out.println(v1.equals(v2)); // true
System.out.println(v1 == v2);      // false
System.out.println(v1 == v3);      // true

equals() vs containsAll()

  • equals()
  • containsAll()

Vector equals() Vector Vector equals()

Java Vector [Java Vector] Java Vector