Promotion
CodeGym University
Learning
Course
Tasks
Surveys & Quizzes
Games
Help
Schedule
Community
Users
Forum
Chat
Articles
Success stories
Activity
Reviews
Subscriptions
Light theme
Authors
Reviews
About us
Start
Start learning
Start learning now
Articles
Authors
All groups
All Articles List
John Selawsky
Senior Java Developer and Tutor at
LearningTree
Write a message
A senior Java developer and Java tutor at Learning Tree International programming courses. Sometimes I write some stupid programming stuff about Java. 7 years experience of Java/J2EE development. In Java We Trust.
Author's articles
John Selawsky
Java Classes
18 March 2022 15:16
Java.lang.Integer Class
Java data types can be conditionally divided into two blocks: primitive and reference (classes). There are several primitive data types in Java, such as integers (byte, short, int, long), floating point numbers (float, double), logical data...
John Selawsky
Java Numbers
7 March 2022 12:34
Java floor() method
A floor function which is also known as the greatest integer function in maths takes a real number “x” as an input. It returns the greatest integer that is less than or equal to input number x. It is normally denoted as floor(x) or ⌊x⌋. It is used...
John Selawsky
Java Collections
7 March 2022 8:49
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.”...
John Selawsky
Loops in Java
1 February 2022 12:29
Java Nested Loops
Java, like most other programming languages, supports nested loops. This means just a loop within a loop. In this article, we are going to find out about how to work with nested loops in Java...
John Selawsky
Java Classes
26 January 2022 8:32
Java.util.Date Class
What is java.util.Date Class? The java.util.Date class provides the date and time in java. This class provides constructors and methods to use the current date and time. To use this class in your code you...
John Selawsky
Inheritance in Java
14 January 2022 12:27
Super keyword in Java
The super keyword is used in different situations. Before getting started with this post we encourage you to learn about inheritance in Java for a better understanding. What is the super keyword in Java?..
John Selawsky
Strings in Java
9 December 2021 12:53
Java String replace() Method
What are the common replace() methods of String class in Java? The String class provides four different kinds of replace() methods in Java. Each of the methods addresses a specific use case. Their names are listed below...
John Selawsky
Strings in Java
16 August 2021 11:57
Reverse a String in Java
What is a Reverse String? “Start reading a String beginning from its last character all the way up to the first character. Bingo! that was your reversed string." Here’s a demonstration of how it will look like...
John Selawsky
Java Types
8 June 2021 5:14
Java Byte Keyword
What is a “byte”? 8 bits (bit is the smallest unit of data containing at most 2 logical states, normally 0 and 1) combine to make a single unit of addressable memory, called a “Byte”. Here’s a theoretical representation of what a byte normally looks like...
John Selawsky
Learning Java
31 March 2021 9:22
Junior → Senior. How Many Years Do You Need to Become a Senior Java Developer
As you may know by now, traditionally in the tech industry developers are divided into four gradations based on their qualification levels: Junior, Middle, Senior and Team Lead. Or five, if you include coding Interns as the lowest-ranked...
John Selawsky
Java Collections
18 November 2020 11:06
HashSet contains() Method in Java
What is a HashSet? HashSet is a built-in datatype in Java, and in layman terms you can say “HashSet is an unordered collection of unique elements.” Have a look at a basic example. HashSet extends (extends means a class is inherited from another class) AbstractSet and...
John Selawsky
Strings in Java
14 September 2020 11:04
Java String contains() Method
This function is specially designed to check if a string ‘contains’ another string or not. If you’re new to this you might end up using it to find a ‘character’. But it won’t serve the purpose. In this article, we’ll address how java.lang.String.contains() is used, implemented...
Show more
1
2
3
Please enable JavaScript to continue using this application.