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Vasyl Malik Java Collections
August 31, 2022 at 10:46 AM
Java Collections sort()One of the most common functions we need as developers dealing with data is sorting--by being able to sort our data, we can optimize our algorithms to run much faster, and find the data it needs to in a fraction of the time that it would take to otherwise. As a quick thought experiment: imagine that you are...
8/31/22
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Oleksandr Miadelets Java Collections
January 12, 2025 at 2:06 PM
Java Queue Interface and implementations Here we are going to discuss the Java Queue interface. You’ll find out what Queue data structure is, how it is represented in Java, what methods are the most important for all queues. Also, what implementations of Queue are in Java language. After that, we take a closer look at the most important...
1/12/25
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Oleksandr Miadelets Java Collections
January 11, 2025 at 8:54 AM
Java Iterator Imagine that you go to the library, and you want to find a particular book. How do you do it? If it’s non-fiction, there’s the Dewey Decimal System. If it’s fiction, they’re sorted in alphabetical order by their last name. Whatever you’re looking for, at some point, you have to go through the books one at a time until you...
1/11/25
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Alex Vypirailenko Java Collections
October 20, 2021 at 1:50 PM
How to Replace an Element in Java ArrayList Simple arrays in Java do not offer any method to update or replace an element. Nevertheless in ArrayList replace is pretty convenient to implement using the set method...
10/20/21
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Milan Vucic Java Collections
February 15, 2025 at 2:03 PM
Java Deque Interface Java Deque is a data structure that combines an ordinary Queue and Stack. You may add and remove elements both to the head and to the tail of the Deque. In the “traditional” queue you add elements to the tail of the line (after the last element) and remove elements from the head of the queue...
2/15/25
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Vasyl Malik Java Collections
August 18, 2022 at 8:04 AM
Collections in Java A collection in java is represented as a container that groups all the elements into a single unit. For example, a mail folder (group of emails), a telephone directory (mapping of names to phone numbers)...
8/18/22
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John Selawsky Java Collections
March 23, 2022 at 12:01 PM
How to update the value of an existing key in HashMap You know that there is always a key and a value in HashMap or any other Map. Key is called a key for a reason, because you get the access to values by the key. The key is unique...
3/23/22
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Jesse Haniel Java Collections
January 13, 2025 at 11:36 AM
Java Priority Queue: not a classical queue In this article we learn a priority queue, Java class, that implements Queue interface. What does a programmer know of regular Queue Interface? First of all, this interface is based on the FIFO principle or “first in first out”. That reminds a regular queue in its common meaning. You want to get coffee from McDrive?
1/13/25
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John Selawsky Java Collections
December 21, 2024 at 8:49 AM
HashMap getOrDefault method in Java What is the getOrDefault method for HashMaps in Java? “The getOrDefault method returns the value mapped to the specified key in a HashMap. If that key is not present then a default value is returned.”...
12/21/24
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Pavlo Plynko Java Collections
January 14, 2025 at 12:24 PM
Java Hashtable Java Hashtable class is one of the oldest members of Java Collection Framework. It is an implementation of mathematical hash table data structure. In Java hashtable internally contains buckets where the key/value pairs are stored. Hashtable is pretty similar to HashMap. The most significant difference between...
1/14/25
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Pavlo Plynko Java Collections
September 8, 2023 at 6:59 AM
Convert List to Array in Java List and arrays are two ways to store data in Java that you will use quite often. In projects where you need to store data without any sort of file handling, list and arrays let you store data throughout the execution of your program. We’ll be using Class ArrayList...
9/8/23
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Volodymyr Portianko Java Collections
February 10, 2025 at 2:20 PM
How to Print an Array in Java Java provides Array data structure to store different elements of the same data type. The elements are stored in contiguous memory. To display the similar contents of the array, the elements are needed to be printed...
2/10/25
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