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Java Collections - PriorityQueue.add() Examples

Java Collections Java Java API 


Class:

java.util.PriorityQueue

java.lang.Objectjava.lang.Objectjava.util.AbstractCollectionjava.util.AbstractCollectionjava.util.CollectionCollectionjava.util.AbstractQueuejava.util.AbstractQueuejava.util.QueueQueuejava.util.PriorityQueuejava.util.PriorityQueuejava.io.SerializableSerializableLogicBig

Method:

public boolean add(E e)

Inserts the specified element into this priority queue. Call to this method is forwarded to offer() method.


Examples


package com.logicbig.example.priorityqueue;

import java.util.PriorityQueue;

public class AddExample {

public static void main(String... args) {
PriorityQueue<String> pq = new PriorityQueue<>();
pq.add("one");
pq.add("two");
System.out.println(pq);
}
}

Output

[one, two]




PriorityQueue does not allow null elements:

package com.logicbig.example.priorityqueue;

import java.util.PriorityQueue;

public class AddExample2 {

public static void main(String... args) {
PriorityQueue<String> pq = new PriorityQueue<>();
pq.add(null);
}
}

Output

Caused by: java.lang.NullPointerException
at java.base/java.util.PriorityQueue.offer(PriorityQueue.java:337)
at java.base/java.util.PriorityQueue.add(PriorityQueue.java:323)
at com.logicbig.example.priorityqueue.AddExample2.main(AddExample2.java:15)
... 6 more




See Also