How to connect to an EC2 instance over SSH

Posted on March 1, 2024 by Andrej Buday

This article is a simple guide detailing the prerequisites and step-by-step procedures for connecting to EC2 instances via SSH. It covers Unix-based systems and Windows users, including the conversion of private key files for PuTTY.

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Simple algorithm for casting strings to double

Posted on February 5, 2024 by Andrej Buday

This article describes a method for converting incorrectly formatted numeric strings in CSV files into doubles by replacing commas with dots and handling various input errors, complemented by a Java util class implementation and tests.

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How to make multipart requests with file and object through autogenerated code defined in OpenAPI

Posted on February 3, 2024 by Andrej Buday

This article explains creating a Spring Boot endpoint using OpenAPI to receive objects and, optionally, files through multipart form data, focusing on deserialization and validation of incoming objects.

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How to make multipart requests with files through autogenerated code defined in OpenAPI

Posted on February 1, 2024 by Andrej Buday

This article provides a clear tutorial on generating code infrastructure defined OpenAPI schema for your custom Spring Boot application and handling multipart file uploads through an autogenerated REST endpoint.

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How to compile and run Java files on Windows

Posted on July 1, 2023 by Andrej Buday

From time to time, you get into a situation you need to compile and run your Java code, and instead of using any build tool or IDE, you need to do it manually. If you are engaged in software development or writing automated script writing, compiling and executing code from the Windows console should be straightforward and effortless.

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Java concurrency interview conversation about passing shared variables to threads

Posted on June 1, 2023 by Andrej Buday

During one interview, I got a pretty nice Java concurrency interview question. It was more or less a conversation between me and the interviewer about how Java handles Threads and passing references, plus ideas on solving concurrency pitfalls.

Let’s take a while and simulate such a conversation so you can be prepared for your next Java concurrency interview.

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7 different ways how to get NumberFormatException in Java

Posted on May 5, 2022 by Andrej Buday

If you get NumberFormatException in Java, it is highly probable because of the following reasons. This article will uncover the NumberFormatException, how you are getting it and what you should do to handle the exception properly.

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How to figure out if a character in a string is a number

Posted on May 3, 2022 by Andrej Buday

This article will show how to figure out if a character in a string is a number. You might be wondering how to do it. There are multiple ways to determine if an individual or series of characters in the string classify as a number. So let’s look at various approaches for determining if the character is a number.

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Developer Notes 001

Posted on May 1, 2022 by Andrej Buday

This article selects a few developer notes collected during the software development, which were unfortunately not enough for a self-standing article.

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How To Turn Number To String With Padded Space or Zeroes

Posted on April 1, 2022 by Andrej Buday

This article will show us how to turn numbers into the String with padded space or numbers.

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