In Java 9 new static factory method has been added to create an immutable Map in Java. In this article we’ll see an example of creating immutable Map using factory method and how it makes it more convenient than the previous option of using Collections.unmodifiableMap(). You can not remove or…
In Java 9 new static factory method has been added to create an immutable Set in Java. In this article we’ll see an example of creating immutable set using factory method and how it makes it more convenient than the previous option of using Collections.unmodifiableSet(). You can not remove or…
In Java 9 Immutable collections were added in Java that makes it easy to create an immutable List, Set or Map. In this article we’ll see how to use Immutable List in Java. Elements cannot be added, removed, or replaced once an immutable list is created. Calling any mutator method…
TreeMap in Java is one of the implementation of the Map interface. How it differs from the other implementation HashMap is that unlike HashMap which is unordered, TreeMap is Sorted. TreeMap is sorted according to the natural ordering of its keys by default. If you want different sort ordering then…
LinkedHashMap in Java is also one of the implementation of the Map interface. How it differs from the other implementation HashMap is that unlike HashMap which is unordered, LinkedHashMap is ordered. LinkedHashMap class in Java also extends HashMap apart from implementing Map interface. LinkedHashMap maintains a doubly-linked list running through…
In Java programming language when you create an array you will have to provide its length. Once created, array is of fixed length and that length can’t be changed. In many cases you may not know the exact length in advanced in such scenarios you can use ArrayList in Java.…
Java Collections framework is an important API in Java programming language. In any Java application if you have to store objects you will certainly use one of the data structure defined in the Java collections. This Java collections tutorial gives an overview of Java collections framework; interfaces and classes that…
HashSet in Java is part of the Java Collections framework and one of the most used Set implementation in Java applications. HashSet class extends AbstractSet class and implements Set, Cloneable and Serializable interfaces. HashSet is backed by a HashMap instance that means HashSet class internally uses HashMap to store its…
This post shows how to sort a HashSet in Java. Since HashSet is an unordered collection so you will need to convert it to another collection in order to sort a HashSet. There are two options to sort a HashSet by converting it to another collection. Convert HashSet to list…
In this post we’ll see how to convert ArrayList to array in Java. Since internal implementation of ArrayList uses an array internally to store its element so ArrayList class itself provides toArray() method to convert ArrayList to array. There are two overloaded toArray() methods. toArray()– Returns an array containing all…
