Hello,
I was tinkering with this a week ago…
Hope this helps:
float[] stuff1 = {1, 2, 3};
float[] stuff2 = {4, 5, 6};
ArrayList list = new ArrayList();
list.add(stuff1);
list.add(stuff2);
printArray(list);
println();
//Print Test 1
println(list.get(0));
println(list.get(1));… Answer from glv on discourse.processing.org
W3Schools
w3schools.com › java › ref_arraylist_add.asp
Java ArrayList add() Method
T refers to the data type of items in the list. ... import java.util.ArrayList; public class Main { public static void main(String[] args) { ArrayList<String> cars = new ArrayList<String>(); cars.add("Volvo"); cars.add("BMW"); cars.add("Ford"); cars.add("Mazda"); cars.add(2, "Toyota"); System.out.println(cars); } }
Stanford
web.stanford.edu › class › archive › cs › cs108 › cs108.1082 › 106a-java-handouts › HO49ArrayList.pdf pdf
CS106A, Stanford Handout #49 Fall, 2004-05 Nick Parlante ArrayList
To add an object to an ArrayList, we pass a pointer to the object we want to add. This · does not copy the object being stored. There is just one object, and we have stored a · pointer to it in the ArrayList. Indeed, copying objects is very rare in Java.
Add an Array to an ArrayList
I’ve created a REALLY simple code snippet to show what I’m trying to do. I need to add an array that I have defined into an ArrayList. I need an ArrayList as I don’t know how many arrays I will end up with. This will Obvs be in a loop but I just wanted to show the problem I’m having ... More on discourse.processing.org
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1
January 6, 2020Adding to an ArrayList Java - Stack Overflow
I am a beginner to java, and need some help. I am trying to convert an Abstract Data type Foo which is an associated list to an Arraylist of the strings B. How do you loop through the list and add each string to the array. More on stackoverflow.com
Is there a way to add elements to an Array List all at once?
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November 2, 2021java - Add String Array to ArrayList - Stack Overflow
@GlacialMan "is it posible to add more arrays in list in the same line of the code" not really; "and how i can now to access to some of elements of array" - aList.get(0);, perhaps you should take a closer look at Collections Trail 2016-04-11T22:52:13.777Z+00:00 More on stackoverflow.com
Videos
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Learn Java arraylists in 9 minutes! 📃 - YouTube
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Convert an Array to an ArrayList (Java Tutorial)
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Java: Convert Array to ArrayList, and ArrayList to Array
Baeldung
baeldung.com › home › java › java array › adding an element to a java array vs an arraylist
Adding an Element to a Java Array vs an ArrayList | Baeldung
April 4, 2025 - Since a Java array is fixed-sized, we need to provide the size while instantiating it. It is not possible to increase the size of the array once it has been instantiated. Instead, we need to create a new array with the adjusted size and copy all the elements from the previous array. ArrayList is a resizable array implementation of the List interface — that is, ArrayList grows dynamically as elements are added to it.
GeeksforGeeks
geeksforgeeks.org › java › java-util-arraylist-add-method-java
Java ArrayList add() Method with Examples - GeeksforGeeks
March 14, 2026 - ... Exception: Throws ... an empty ArrayList ArrayList<Integer> al = new ArrayList<>(); // Use add() method to // add elements in the list al.add(10); al.add(20); al.add(30); al.add(40); System.out.println("" + ...
W3Schools
w3schools.com › java › java_arraylist.asp
Java ArrayList
It is part of the java.util package and implements the List interface. The difference between a built-in array and an ArrayList in Java, is that the size of an array cannot be modified (if you want to add or remove elements to/from an array, you have to create a new one).
Processing Foundation
discourse.processing.org › beginners
Add an Array to an ArrayList - Beginners - Processing Community Forum
January 6, 2020 - I’ve created a REALLY simple code snippet to show what I’m trying to do. I need to add an array that I have defined into an ArrayList. I need an ArrayList as I don’t know how many arrays I will end up with. This will Obvs be in a loop but I just wanted to show the problem I’m having When I run the following float[] stuff = {1,2,3}; ArrayList list = new ArrayList (); list.add(stuff); printArray(list); I am hoping to see 1,2,3 in the first entry for the ArrayList. instead I j...
Software Testing Help
softwaretestinghelp.com › home › java › how to add elements to an array in java
How To Add Elements To An Array In Java
April 1, 2025 - Hence you can dynamically increase the size of the array list and add as many elements to it. Thus you can use ArrayList as an intermediate structure while adding elements to the array ... First, you can convert array to ArrayList using ‘asList ()’ method of ArrayList. Add an element to the ArrayList using the ‘add’ method. Convert the ArrayList back to the array using the ‘toArray()’ method. Let’s put these steps into an implementation. import java.util.*; class Main { public static void main(String[] args) { // Original array with size 5 Integer odd_Array[] = { 1,3,5,7,9 }; //
Top answer 1 of 7
51
Instantiate a new ArrayList:
List<String> myList = new ArrayList<String>();
Iterate over your data structure (with a for loop, for instance, more details on your code would help.) and for each element (yourElement):
myList.add(yourElement);
2 of 7
13
If you have an arraylist of String called 'foo', you can easily append (add) it to another ArrayList, 'list', using the following method:
ArrayList<String> list = new ArrayList<String>();
list.addAll(foo);
that way you don't even need to loop through anything.
Reddit
reddit.com › r/javahelp › is there a way to add elements to an array list all at once?
r/javahelp on Reddit: Is there a way to add elements to an Array List all at once?
November 2, 2021 -
For example I can do this with a basic integer array:
int[] test1 = new int[]{2, 1, 5, 1, 3, 2};But with an Array list I have to add them one at a time like this
List<Integer> test1 = new ArrayList<Integer>(); test1.add(2); test1.add(1); test1.add(3);
?
Top answer 1 of 4
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If you know your values before hand you can do List.of(x, y, z,...); Note that this will give you an immutable list
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There are many ways, here are some I find most elegant: List list1 = new ArrayList<>(List.of(1, 2, 3, 4)); // or List list2 = new ArrayList<>(Arrays.asList(1, 2, 3, 4));
How to do in Java
howtodoinjava.com › home › collections framework › java arraylist › java arraylist add() – add a single element to list
Java ArrayList add() - Add a Single Element to List
August 7, 2023 - The ArrayList.add() in Java adds a single element to the list, either at the end of the list or at the specified index position. Always use generics for compile-time type safety while adding the element to the arraylist.
Dot Net Perls
dotnetperls.com › collections-addall-java
Java - Collections.addAll: Add Array to ArrayList - Dot Net Perls
Detail This method receives 2 ... values = { "cat", "dog", "bird" }; // Create a one-element ArrayList. ArrayList<String> list = new ArrayList<>(); list.add("elephant"); System.out.println(list); // Add all elements to the ArrayList from an array....
Vultr
docs.vultr.com › java › standard-library › java › util › ArrayList › add
Java ArrayList add() - Add Element | Vultr Docs
November 29, 2024 - The add() method in Java's ArrayList class is one of the most frequently used operations for dynamically managing collections of objects. This method allows for the insertion of elements into an ArrayList, providing flexibility and ease of use ...
Oracle
docs.oracle.com › javase › 8 › docs › api › java › util › ArrayList.html
ArrayList (Java Platform SE 8 )
April 21, 2026 - The size, isEmpty, get, set, iterator, and listIterator operations run in constant time. The add operation runs in amortized constant time, that is, adding n elements requires O(n) time. All of the other operations run in linear time (roughly speaking). The constant factor is low compared to that for the LinkedList implementation. Each ArrayList instance has a capacity.
BeginnersBook
beginnersbook.com › 2022 › 08 › add-multiple-items-to-an-arraylist-in-java
Add Multiple Items to an ArrayList in Java
December 1, 2024 - We are adding multiple elements to it using Collections.addAll() method by passing list as the first argument and items as the second argument. import java.util.*; public class JavaExample { public static void main(String[] args) { ArrayList<String> list = new ArrayList<String>(); ...
TutorialsPoint
tutorialspoint.com › article › how-do-i-add-an-element-to-an-array-list-in-java
How do I add an element to an array list in Java?
March 14, 2026 - The following example shows how to add elements to an ArrayList using both forms of the add() method ? import java.util.ArrayList; import java.util.List; public class CollectionsDemo { public static void main(String[] args) { List<Integer> list ...
Baeldung
baeldung.com › home › java › java collections › add multiple items to an java arraylist
Add Multiple Items to an Java ArrayList | Baeldung
January 8, 2024 - List<Integer> list = new ArrayList<>(); Integer[] otherList = new Integer[] {1, 2, 3, 4, 5}; Collections.addAll(list, otherList); Similarly to the way explained in the above section, the contents of both lists here will refer to the same objects.
DigitalOcean
digitalocean.com › community › tutorials › java-list-add-addall-methods
How To Use add() and addAll() Methods for Java List | DigitalOcean
September 10, 2025 - Vector: Similar to ArrayList but with synchronization overhead · Adding single elements · Inserting at specific positions (when necessary) Building lists incrementally · Working with small datasets where simplicity matters · package com.journaldev.examples; import java.util.ArrayList; import java.util.LinkedList; import java.util.List; public class ListAddExamples { public static void main(String[] args) { // Example 1: Basic add() operations List<String> vowels = new ArrayList<>(); vowels.add("A"); // [A] vowels.add("E"); // [A, E] vowels.add("U"); // [A, E, U] System.out.println("After a
Codecademy
codecademy.com › docs › java › arraylist › .add()
Java | ArrayList | .add() | Codecademy
March 21, 2022 - Adds an element to an ArrayList.
BeginnersBook
beginnersbook.com › 2013 › 12 › java-arraylist-add-method-example
Java ArrayList add() Method Example
September 17, 2022 - The reason the following program throws IndexOutOfBoundsException is: The ArrayList grows in size dynamically, you cannot add third element in the ArrayList without adding the second element, which is what we are trying to do in the following program. import java.util.ArrayList; public class JavaExample{ public static void main(String[] args){ ArrayList<String> list = new ArrayList<>(); list.add(0, "Hi"); // ["Hi"] list.add(0, "Hello");// ["Hello", "Hi"] // throws IndexOutOfBoundsException list.add(3, "Bye"); } }