An **#key# ArrayDeque: Array Double Ended Queue #key#** is a growable array that allows us to add or remove an element from both the front and back. 

This class is the implementation class of the `Deque` interface. `ArrayDeque` can be used as both a Stack or Queue. 

> `Null` elements are prohibited. 

# 
## What is the `contains` method of the `ArrayDeque`?

The **`contains` method** can be used to check if the specified element is present in the `ArrayDeque` object.

## Syntax 

---
```java
public boolean contains(Object o)
```
---

## Parameters

This method takes the element to be checked as a parameter.

## Return value

This method returns `true` if the passed element is present in the `deque`. Otherwise, it returns `false`.

# 
## Code 

The code below demonstrates how to use the `contains` method.

import java.util.ArrayDeque;
class Contains{
    public static void main( String args[] ) {
      ArrayDeque<String> arrayDeque = new ArrayDeque<>();
      arrayDeque.add("1");
      arrayDeque.add("2");
      arrayDeque.add("3");
      System.out.println("The arrayDeque is " + arrayDeque);
      
      System.out.println("Check if 1 present in the arrayDeque : " + arrayDeque.contains("1"));
      System.out.println("Check if 4 present in the arrayDeque : " + arrayDeque.contains("4"));
    }
}

# 
## Explanation 

In the above code:

* In line 1, we import the `ArrayDeque` class.

* In line 4, we create an `ArrayDeque` object with the name `arrayDeque`. 

* In line 5 to 7, we use the `add()` method of the `arrayDeque` object to add three elements (`"1","2","3"`) to `deque`.

* In line 10, we use the `contains()` method of the `arrayDeque` object to check if the element `"1"` is present. 

  In our case, `true` will be returned because `"1"` is available in the `arrayDeque` object.

* In line 11, we use the `contains()` method of the `arrayDeque` object to check if the element `"4"` is present. 

  In our case, `false` will be returned because `"4"` is not available in the `arrayDeque` object.

What is the ArrayDeque.contains method in Java?

ArrayDeque's `contains` method checks for the presence of an element and returns true or false accordingly.

What is the ArrayDeque.contains method in Java?

What is the contains method of the ArrayDeque?

Syntax

Parameters

Return value

Code

Explanation

What is the `contains` method of the `ArrayDeque`?