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copied!<p>Arraylist stores the reference and does not copy/create new objects. If you change the stored object reference, it will be reflected in the arrayList as well. Here is a sample code to demonstrate that:</p> <pre><code>package arraylistExample; import java.util.ArrayList; /** * Class represeting entity to be stored in Arraylist * */ class Person { private String name; private int age; private String address; public Person(String name, int age, String address) { super(); this.name = name; this.age = age; this.address = address; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age) { this.age = age; } public String getAddress() { return address; } public void setAddress(String address) { this.address = address; } @Override public String toString() { return "Person [name=" + name + ", age=" + age + ", address=" + address + "]"; } } </code></pre> <p>.</p> <pre><code>/** * Public class to run the demo * */ public class ArraylistObjectModify { public static void main(String args[]) { // Add an arraylist and add elements to it ArrayList<Person> personList = new ArrayList<Person>(); personList.add(new Person("Juned",32,"Bangalore")); personList.add(new Person("Ahsan",31,"Delhi")); personList.add(new Person("Sniper",1,"Grave")); //Print list elements before change System.out.println("Arraylist pre objects modification"); System.out.println("----------------------------------"); for(Person person:personList) { System.out.println(person); } for(Person person:personList) { if(person.getName().equals("Juned")) { person.setName("ChangedJuned"); person.setAddress("Hola-lulu"); } } //Print list elements after change System.out.println("Arraylist post objects modification"); System.out.println("----------------------------------"); for(Person person:personList) { System.out.println(person); } } } </code></pre>

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