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Java Vector contains() Method with Example

Vector Class contains() method: Here, we are going to learn about the contains() method of Vector Class with its syntax and example.
Submitted by Preeti Jain, on March 15, 2020

Vector Class contains() method

• contains() method is available in java.util package.
• contains() method is used to check whether the given object (ob) exists or not exists in this Vector.
• contains() method is a non-static method, it is accessible with the class object only and if we try to access the method with the class name then we will get an error.
• contains() method may throw an exception at the time of checking the existence of the given object.
  • ClassCastException: This exception may throw when the given object is incompatible to check.
  • NullPointerException: This exception may throw when the given parameter is null exists.

Syntax:

    public boolean contains(Object ob);

Parameter(s):

• Object ob – represents the object to check its existence in this Vector.

Return value:

The return type of the method is boolean, it returns true when the given object exists otherwise it returns false.

Example:

// Java program to demonstrate the example 
// of boolean contains(Object ob) method 
// of Vector 

import java.util.Vector;

public class ContainsOfVector {
    public static void main(String[] args) {
        // Instantiates a Vector object  with
        // initial capacity of "10"
        Vector < String > v = new Vector < String > (10);

        // By using add() method is to add the
        // elements in this v
        v.add("C");
        v.add("C++");
        v.add("JAVA");

        // Display Vector 
        System.out.println("v: " + v);

        // By using contains(JAVA) method is to
        // check whether the given object "JAVA"
        // exists or not exists
        boolean status = v.contains("JAVA");

        // Display status
        System.out.println("v.contains(JAVA): " + status);
    }
}

Output

v: [C, C++, JAVA]
v.contains(JAVA): true