Arraylist.contains() Method in Java

Last Updated : 10 Dec, 2024

In Java, the ArrayList contains() method is used to check if the specified element exists in an ArrayList or not.

Example: Here, we will use the contains() method to check if the ArrayList of Strings contains a specific element.

Java

// Java program to demonstrate the use of contains() 
// method with ArrayList of Strings
import java.util.ArrayList;

public class GFG {
    public static void main(String[] args) {
      
        // Create an ArrayList of Strings
        ArrayList<String> s = new ArrayList<>();
        s.add("Apple"); 
        s.add("Blueberry"); 
        s.add("Strawberry"); 

        // Check if "Grapes" exists in the ArrayList
        System.out.println(s.contains("Grapes")); 

        // Check if "Apple" exists in the ArrayList
        System.out.println(s.contains("Apple")); 
    }
}

Output

false
true

Syntax of ArrayList.contains() Method

public boolean contains(Object o)

Parameter: o: The element whose presence in the ArrayList is to be tested.
Returns: It returns true if the specified element is found in the list else it returns false.

Other Examples of Java ArrayList.contains()

Example 2: Here, we are using the contains() method to check if the ArrayList of Integers contains a specific number.

Java

// Java program to demonstrate the use of contains() 
// method with ArrayList of Integers
import java.util.ArrayList;

public class GFG {
    public static void main(String[] args) {
      
        // Create an ArrayList of Integers
        ArrayList<Integer> arr = new ArrayList<>();
        arr.add(10);
        arr.add(20); 
        arr.add(30); 

        // Check if 20 exists in the ArrayList
        System.out.println(arr.contains(20)); 

        // Check if 40 exists in the ArrayList
        System.out.println(arr.contains(40)); 
    }
}

Output

true
false

Example 3: Here, we are using contains() method to verify if the ArrayList of Strings contains a specific name.

Java

// Java program to demonstrate the use of contains() 
// method with ArrayList of Strings (Names)
import java.util.ArrayList;

public class GFG {
    public static void main(String[] args) {
      
        // Create an ArrayList of Strings
        ArrayList<String> s = new ArrayList<>();
        s.add("Ram");
        s.add("Shyam");  
        s.add("Gita"); 

        // Check if "Hari" exists in the ArrayList
        System.out.println(s.contains("Hari"));

        // Check if "Ram" exists in the ArrayList
        System.out.println(s.contains("Ram")); 
    }
}