DelayQueue take() method in Java with Examples Last Updated : 12 May, 2021 Summarize Comments Improve Suggest changes Share Like Article Like Report The take() method of DelayQueue is used to retrieve head of the DelayQueue and also removes it. Thus, the size of the DelayQueue is reduced. This function waits if an element with expired delay is available on this queue. Syntax: public E take () Parameters: This method accepts no parameters.Return Value: The function returns the head of the DelayQueue.Exception: This method throws InterruptedException if interrupted while waiting.Below programs illustrate the DelayQueue.take() method:Program: Java // Java Program Demonstrate DelayQueue take() method import java.util.concurrent.*; import java.util.*; // The DelayObject for DelayQueue // It must implement Delayed and // its getDelay() and compareTo() method class DelayObject implements Delayed { private String name; private long time; // Constructor of DelayObject public DelayObject(String name, long delayTime) { this.name = name; this.time = System.currentTimeMillis() + delayTime; } // Implementing getDelay() method of Delayed @Override public long getDelay(TimeUnit unit) { long diff = time - System.currentTimeMillis(); return unit.convert(diff, TimeUnit.MILLISECONDS); } // Implementing compareTo() method of Delayed @Override public int compareTo(Delayed obj) { if (this.time < ((DelayObject)obj).time) { return -1; } if (this.time > ((DelayObject)obj).time) { return 1; } return 0; } // Implementing toString() method of Delayed @Override public String toString() { return "\n{" + " " + name + ", time=" + time + "}"; } } // Driver Class public class GFG { public static void main(String[] args) throws InterruptedException { // create object of DelayQueue // using DelayQueue() constructor BlockingQueue<DelayObject> DQ = new DelayQueue<DelayObject>(); // Add numbers to end of DelayQueue // using add() method DQ.add(new DelayObject("A", 1)); DQ.add(new DelayObject("B", 2)); DQ.add(new DelayObject("C", 3)); DQ.add(new DelayObject("D", 4)); // print the size of DelayQueue System.out.println("Size of the DelayQueue: " + DQ.size()); // print queue System.out.println("DelayQueue: " + DQ); // take() function will retrieve and remove the head of DelayQueue System.out.println("Head of the DelayQueue:" + DQ.take()); // print the size of DelayQueue System.out.println("Size of the DelayQueue: " + DQ.size()); // print queue System.out.println("DelayQueue: " + DQ); } } Output: Size of the DelayQueue: 4 DelayQueue: [ { A, time=1546842594283}, { B, time=1546842594284}, { C, time=1546842594285}, { D, time=1546842594286}] Head of the DelayQueue: { A, time=1546842594283} Size of the DelayQueue: 3 DelayQueue: [ { B, time=1546842594284}, { D, time=1546842594286}, { C, time=1546842594285}] Comment More infoAdvertise with us Next Article DelayQueue peek() method in Java with Examples P ProgrammerAnvesh Follow Improve Article Tags : Java Java-Collections Java - util package Java-Functions java-DelayQueue +1 More Practice Tags : JavaJava-Collections Similar Reads DelayQueue put() method in Java with Examples The put(E ele) method of DelayQueue class in Java is used to inserts a given element into the delay queue container. 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