ConcurrentLinkedQueue size() method in Java Last Updated : 26 Nov, 2018 Comments Improve Suggest changes Like Article Like Report The size() method of ConcurrentLinkedQueue is used to returns number of elements that this ConcurrentLinkedQueue contains. Syntax: public int size() Returns: This method number of elements in this ConcurrentLinkedQueue. Below programs illustrate size() method of ConcurrentLinkedQueue: Example 1: Java // Java Program Demonstrate size() // method of ConcurrentLinkedQueue import java.util.concurrent.*; public class GFG { public static void main(String[] args) { // create an ConcurrentLinkedQueue ConcurrentLinkedQueue<Integer> queue = new ConcurrentLinkedQueue<Integer>(); // Add Numbers to queue queue.add(4353); queue.add(7824); queue.add(78249); queue.add(8724); // Displaying the existing ConcurrentLinkedQueue System.out.println("ConcurrentLinkedQueue: " + queue); // apply size() int size = queue.size(); // print after applying size method System.out.println("Size of ConcurrentLinkedQueue: " + size); } } Output: ConcurrentLinkedQueue: [4353, 7824, 78249, 8724] Size of ConcurrentLinkedQueue: 4 Example 2: Java // Java Program Demonstrate size() // method of ConcurrentLinkedQueue import java.util.concurrent.*; public class GFG { public static void main(String[] args) { // create an ConcurrentLinkedQueue ConcurrentLinkedQueue<String> queue = new ConcurrentLinkedQueue<String>(); // Add String to queue queue.add("Aman"); queue.add("Amar"); queue.add("Sanjeet"); queue.add("Rabi"); // Displaying the existing ConcurrentLinkedQueue System.out.println("ConcurrentLinkedQueue: " + queue); // apply size() on queue int size = queue.size(); // print after applying size method System.out.println("Size of ConcurrentLinkedQueue: " + size); // removal of some elements queue.poll(); queue.poll(); // get size of ConcurrentLinkedQueue again size = queue.size(); // Displaying the existing ConcurrentLinkedQueue System.out.println("After 2 removal of elements\n" + "ConcurrentLinkedQueue: " + queue); // print after applying size method System.out.println("Size of ConcurrentLinkedQueue: " + size); } } Output: ConcurrentLinkedQueue: [Aman, Amar, Sanjeet, Rabi] Size of ConcurrentLinkedQueue: 4 After 2 removal of elements ConcurrentLinkedQueue: [Sanjeet, Rabi] Size of ConcurrentLinkedQueue: 2 Reference: https://docs.oracle.com/javase/8/docs/api/java/util/concurrent/ConcurrentLinkedQueue.html#size-- Comment More infoAdvertise with us Next Article ConcurrentLinkedDeque size() method in Java A AmanSingh2210 Follow Improve Article Tags : Java Java-Collections Java - util package java-basics Java-Functions Java-ConcurrentLinkedQueue +2 More Practice Tags : JavaJava-Collections Similar Reads ConcurrentLinkedDeque size() method in Java The size() method of ConcurrentLinkedDeque class in Java is used to find the number of elements present in the ConcurrentLinkedDeque container. In other words, this method tells the current capacity of the container. The value returned by this method is of integral type and in case if the container 2 min read ConcurrentLinkedDeque size() method in Java The size() method of ConcurrentLinkedDeque class in Java is used to find the number of elements present in the ConcurrentLinkedDeque container. In other words, this method tells the current capacity of the container. The value returned by this method is of integral type and in case if the container 2 min read ConcurrentLinkedQueue peek() method in Java The peek() method of ConcurrentLinkedQueue is used to return the head of the ConcurrentLinkedQueue. It retrieves but does not remove, the head of this ConcurrentLinkedQueue. If the ConcurrentLinkedQueue is empty then this method returns null. Syntax: public E peek() Returns: This method returns the 2 min read ConcurrentLinkedQueue peek() method in Java The peek() method of ConcurrentLinkedQueue is used to return the head of the ConcurrentLinkedQueue. It retrieves but does not remove, the head of this ConcurrentLinkedQueue. If the ConcurrentLinkedQueue is empty then this method returns null. Syntax: public E peek() Returns: This method returns the 2 min read ConcurrentLinkedQueue offer() method in Java The offer() method of ConcurrentLinkedQueue is used to insert the element, passed as parameter, at the tail of this ConcurrentLinkedQueue. This method returns True if insertion is successful. ConcurrentLinkedQueue is unbounded, so this method offer() will never returns false. Syntax: public boolean 2 min read ConcurrentLinkedQueue offer() method in Java The offer() method of ConcurrentLinkedQueue is used to insert the element, passed as parameter, at the tail of this ConcurrentLinkedQueue. This method returns True if insertion is successful. ConcurrentLinkedQueue is unbounded, so this method offer() will never returns false. Syntax: public boolean 2 min read Like