ConcurrentLinkedDeque offerLast() Method in Java
Last Updated :
26 Nov, 2018
The java.util.concurrent.ConcurrentLinkedDeque.offerLast() method is an inbuilt method in Java which inserts the specified element, passed as a parameter, to the end of the deque.
Syntax:
Conn_Linked_Deque.offerLast(Object elem)
Parameters: The method accepts a parameter
elem which species the element to be inserted to the end of the deque.
Return Value: The function returns
True if the element is successfully added into the deque and returns
False otherwise.
Exception: The function throws a
NullPointerException if the passed parameter is
NULL.
Below programs illustrate the
ConcurrentLinkedDeque.offerLast() method:
Program 1:
Java
/* Java Program to Demonstrate offerLast()
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("Elements in Deque: "
+ cld);
// Displaying the Last element
System.out.println("The Last element is: " +
cld.getLast());
/* Insert an element at the tail
of the deque */
if (cld.offerLast("GFG")) {
// Displaying the Last element
System.out.println("The Inserted element is: " +
cld.getLast());
}
// Displaying the Deque
System.out.println("Elements in Deque: "
+ cld);
// Displaying the Last element
System.out.println("The Last element is: " +
cld.getLast());
}
}
Output:
Elements in Deque: [Welcome, To, Geeks, 4, Geeks]
The Last element is: Geeks
The Inserted element is: GFG
Elements in Deque: [Welcome, To, Geeks, 4, Geeks, GFG]
The Last element is: GFG
Program 2:
Java
/* Java Program to Demonstrate offerLast()
method of ConcurrentLinkedDeque */
import java.util.concurrent.*;
class GFG {
public static void main(String[] args)
{
// Creating an empty Deque
ConcurrentLinkedDeque<Integer> cld =
new ConcurrentLinkedDeque<Integer>();
// Add elements into the Deque
cld.add(12);
cld.add(43);
cld.add(29);
cld.add(16);
cld.add(70);
// Displaying the Deque
System.out.println("Elements in Deque: "
+ cld);
// Displaying the Last element
System.out.println("The Last element is: " +
cld.getLast());
try {
cld.offerLast(null);
}
catch (Exception e) {
System.out.println(e);
}
/* Insert an element at the tail
of the deque */
if (cld.offerLast(24)) {
// Displaying the Last element
System.out.println("The Inserted element is: "
+ cld.getLast());
}
// Displaying the Deque
System.out.println("Elements in Deque: "
+ cld);
// Displaying the Last element
System.out.println("The Last element is: " +
cld.getLast());
}
}
Output:
Elements in Deque: [12, 43, 29, 16, 70]
The Last element is: 70
java.lang.NullPointerException
The Inserted element is: 24
Elements in Deque: [12, 43, 29, 16, 70, 24]
The Last element is: 24
Reference: https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ConcurrentLinkedDeque.html#offerLast()