Arraylist.contains() in Java

ArrayList contains() method in Java is used for checking if the specified element exists in the given list or not.

Syntax:

public boolean contains(Object)
object-element to be searched for

Parameters:
object- element whose presence in this list is to be tested

Returns:
It returns true if the specified element is found in the list else it returns false.

Code#1: Demonstrate the working of the method contains() in integer



// Java code to demonstrate the working of
// contains() method in ArrayList
  
// for ArrayList functions
import java.util.ArrayList;
  
class GFG {
    public static void main(String[] args)
    {
  
        // creating an Empty Integer ArrayList
        ArrayList<Integer> arr = new ArrayList<Integer>(4);
  
        // using add() to initialize values
        // [1, 2, 3, 4]
        arr.add(1);
        arr.add(2);
        arr.add(3);
        arr.add(4);
  
        // use contains() to check if the element
        // 2 exits or not
        boolean ans = arr.contains(2);
  
        if (ans)
            System.out.println("The list contains 2");
        else
            System.out.println("The list does not contains 2");
  
        // use contains() to check if the element
        // 5 exits or not
        ans = arr.contains(5);
  
        if (ans)
            System.out.println("The list contains 5");
        else
            System.out.println("The list does not contains 5");
    }
}

Output:

The list contains 2
The list does not contains 5

Code#2: Demonstrate the working of the method contains() in string

// Java code to demonstrate the working of
// contains() method in ArrayList of string
  
// for ArrayList functions
import java.util.ArrayList;
  
class GFG {
    public static void main(String[] args)
    {
  
        // creating an Empty String ArrayList
        ArrayList<String> arr = new ArrayList<String>(4);
  
        // using add() to initialize values
        // ["geeks", "for", "geeks"]
        arr.add("geeks");
        arr.add("for");
        arr.add("geeks");
  
        // use contains() to check if the element
        // "geeks" exits or not
        boolean ans = arr.contains("geeks");
  
        if (ans)
            System.out.println("The list contains geeks");
        else
            System.out.println("The list does not contains geeks");
  
        // use contains() to check if the element
        // "coding" exits or not
        ans = arr.contains("coding");
  
        if (ans)
            System.out.println("The list contains coding");
        else
            System.out.println("The list does not contains coding");
    }
}

Output:

The list contains geeks
The list does not contains coding

Practical Application:
In search operations, we can check if a given element exists in a list or not.

Reference:
Oracle Docs



My Personal Notes arrow_drop_up

Striver(underscore)79 at Codechef

If you like GeeksforGeeks and would like to contribute, you can also write an article using contribute.geeksforgeeks.org or mail your article to contribute@geeksforgeeks.org. See your article appearing on the GeeksforGeeks main page and help other Geeks.

Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above.




Practice Tags :

Recommended Posts:



2 Average Difficulty : 2/5.0
Based on 1 vote(s)






User Actions