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Java Collections - ArrayDeque.push() Examples

[Last Updated: Dec 10, 2025]

Java Collections Java Java API 

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Class:

java.util.ArrayDeque

java.lang.Objectjava.lang.Objectjava.util.AbstractCollectionjava.util.AbstractCollectionjava.util.CollectionCollectionjava.util.ArrayDequejava.util.ArrayDequejava.util.DequeDequejava.lang.CloneableCloneablejava.io.SerializableSerializableLogicBig

Method:

public void push(E e)

Inserts the element at the front of this deque.

This method is equivalent to addFirst().


Examples


package com.logicbig.example.arraydeque;

import java.util.ArrayDeque;

public class PushExample {

    public static void main(String... args) {
        ArrayDeque<Integer> ad = new ArrayDeque<>();
        ad.push(3);
        System.out.println(ad);
    }
}

Output

[3]
JDK 25




package com.logicbig.example.arraydeque;

import java.util.ArrayDeque;

public class PushExample2 {

    public static void main(String... args) {
        ArrayDeque<Integer> ad = new ArrayDeque<>();
        ad.push(null);
    }
}

Output

java.lang.NullPointerException
    at java.util.ArrayDeque.addFirst (ArrayDeque.java:284)
    at java.util.ArrayDeque.push (ArrayDeque.java:577)
    at com.logicbig.example.arraydeque.PushExample2.main (PushExample2.java:14)
    at jdk.internal.reflect.DirectMethodHandleAccessor.invoke (DirectMethodHandleAccessor.java:104)
    at java.lang.reflect.Method.invoke (Method.java:565)
    at org.codehaus.mojo.exec.AbstractExecJavaBase.executeMainMethod (AbstractExecJavaBase.java:402)
    at org.codehaus.mojo.exec.ExecJavaMojo.executeMainMethod (ExecJavaMojo.java:142)
    at org.codehaus.mojo.exec.AbstractExecJavaBase.doExecClassLoader (AbstractExecJavaBase.java:377)
    at org.codehaus.mojo.exec.AbstractExecJavaBase.lambda$execute$0 (AbstractExecJavaBase.java:287)
    at java.lang.Thread.run (Thread.java:1474)
JDK 25

See Also