Java immutable list. main() will throw an exception.

Java immutable list. util. In this quick tutorial, we’ll explore how to achieve that in Java. An unmodifiable list is a wrapper around an existing list that throws UnsupportedOperationException on Mar 7, 2025 · In Java, immutable objects ensure thread safety and prevent unintended modifications, fostering robust and reliable code. You can't add to, remove from or clear them, but the underlying collection can change. of () Method? The List. Introduction In Java, immutable objects are designed to have their state remain unchanged throughout their lifetime to ensure thread safety and prevent unintended modifications, fostering robust and reliable code. . With Java 9, new factory methods are added to List, Set and Map interfaces to create immutable instances. However, sometimes, we want to add elements to an immutable list. May 20, 2015 · You pass in your original ArrayList and it returns a list that throws an exception if you try to add, remove or shift elements. These factory methods are convenience factory methods to create a collection in less verbose and in a concise way. Learn how to create and utilize immutable lists in Java with best practices and examples in this comprehensive tutorial. Here's a quote from guava's ImmutableList Unlike Collections. unmodifiableList(java. However, there are scenarios where applications need to create a modified version of an immutable object. In this example, I’ll demonstrate how to modify an immutable list by Convenience static factory methods on the List, Set, and Map interfaces let you easily create unmodifiable lists, sets, and maps. Convenience static factory methods on the List, Set, and Map interfaces, which were added in JDK 9, let you easily create immutable lists, sets, and maps. It provides a way to create immutable (unmodifiable) views of lists. Apr 4, 2025 · This tutorial illustrates how to easily create an unmodifiable List out of an existing ArrayList using either the core JDK, Google Guava or Apache Commons Collections. of () method provides a convenient way to create immutable lists, meaning that once the list is created, its contents cannot be changed. Immutable collections can't be changed at all - they don't wrap another collection - they have their own elements. In this post, I show you how to create an immutable list using Java 9 provided List. It means that the content of the List are fixed or constant after declaration, that is, they are read-only. unmodifiableList Last modified: April 20, 2025 The Collections. List<? extends T Apr 20, 2025 · Java Collections. unmodifiableList(beanList); instead of return beanList; at the end of getImmutableList(). Dec 4, 2024 · What Is Java’s List. For example, use return Collections. Unmodifiable collections are usually read-only views (wrappers) of other collections. main() will throw an exception. This Convenience static factory methods on the List, Set, and Map interfaces let you easily create unmodifiable lists, sets, and maps. This is useful when you need to share a list but prevent modifications. Mar 7, 2025 · Learn how to choose between Unmodifiable and Immutable Collections in Java. unmodifiableList method is part of Java's Collections Framework. of () static factory method. 2. Introduction to the Problem May 13, 2024 · 1. Jul 11, 2025 · ImmutableList, as suggested by the name, is a type of List which is immutable.