The java.util.concurrent.ConcurrentLinkedDeque.contains() method is an inbuilt method in Java which checks if the specified element, passed as a parameter, is present in the deque or not.
Syntax:
public boolean contains(Object elem)
Parameters: The method accepts a parameter elem which checks if the specified element is present in the deque or not.
Return Value: The function returns True if the element is present in the deque and returns False otherwise.
Below programs illustrate the ConcurrentLinkedDeque.contains() method:
Program 1:
// Java Program to Demonstrate contains()// method of ConcurrentLinkedDeque  import java.util.concurrent.*;  class GFG {    public static void main(String[] args)    {          // Creating an empty Deque        ConcurrentLinkedDeque<String> cld = new ConcurrentLinkedDeque<String>();          // Add elements into the Deque        cld.add("Welcome");        cld.add("To");        cld.add("Geeks");        cld.add("4");        cld.add("Geeks");          // Displaying the Deque        System.out.println("ConcurrentLinkedDeque: "                           + cld);          // Check if GFG is present using contains()        if (cld.contains("GFG")) {              // Displaying message            System.out.println("GFG is present");        }        else {              // Displaying message            System.out.println("GFG is not present");        }    }} |
Output:
ConcurrentLinkedDeque: [Welcome, To, Geeks, 4, Geeks] GFG is not present
Program 2:
// Java Program to Demonstrate contains()// method of ConcurrentLinkedDeque  import java.util.concurrent.*;  class GFG {    public static void main(String[] args)    {          // Creating an empty Deque        ConcurrentLinkedDeque<String> cld = new ConcurrentLinkedDeque<String>();          // Add elements into the Deque        cld.add("Welcome");        cld.add("To");        cld.add("Geeks");        cld.add("4");        cld.add("Geeks");          // Displaying the Deque        System.out.println("ConcurrentLinkedDeque: "                           + cld);          // Check if Geeks is present using contains()        if (cld.contains("Geeks")) {              // Displaying message            System.out.println("Geeks is present");        }        else {              // Displaying message            System.out.println("Geeks not present");        }    }} |
Output:
ConcurrentLinkedDeque: [Welcome, To, Geeks, 4, Geeks] Geeks is present
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