Let’s face it: certifiates, key management, ssl/tls has never been any fun for any Java developer. That’s why I was also avoided this topic for as long as possible. And the time came to finally gather all I know , or rather: what I don’t know, just for reference.
ISO OSI = International Organization for Standardization Open Systems Interconnection
ISO OSI model is conceptual framework:
ScopedValue is a value that can be seen and used in methods, but hasn’t been passed to them as a parameter. Untill recently this was possible in Java language by means of ThreadLocal variables. Let’s look at ThreadLocals for a moment to refresh our knowledge and let’s see what new features are being introduced by newer replacements, that is: ScopedValues.
ThreadLocal variables are typically declared as private global variables (static fields) and ensure that the value we read from them (using the get() method) is the same value that was previously stored in them (using the set() method) within the same thread (or the one returned by calling the protected initialValue() method that returns the initial value of the ThreadLocal variable).
This is a real thing! Java 21 feels almost as a different programming language! Changes planned to be released in Sptember 2023 (in just a month!) can be roghly grouped into two categories:
Here are the most important and - in my opinion - the most interesting changes that await us in Java 21. They are not revolutionary, but they make writing code - and, what is even more important, reading it - much easier.
switch
These are low-level changes, important for library creators (vector API, FFI, cryptography), or related to "code clean-up." They are probably less interesting for the typical programmer, although it's worth taking a look at the descriptions in JEPs to have a general idea of what they are about.
We will have new interfaces which would be able to correctly model the encounter order. The API we have so far (let me say this: all Collection API) is a bit chaotic: taking first or last element from different collections has different API:
You can easily try out the new features in Java 21 that I wrote about in the previous post. You don’t need to install anything. Just follow these steps:
Here’s how to do it in Ubuntu Linux:
Java has allowed concurrent programming since version 1.0 through the use of the Thread class.
This capability was introduced in 1996 (I celebrated my 18th birthday that year!), but it quickly became evident that it wasn’t straightforward. Larger and more complex applications required better tools to handle threads.
The standard Java library lacked essential constructs for modeling certain concurrent programming patterns, and the code was often hard to read and prone to errors.
Excell files circulate in the veins of large companies. Ther are times when you want to extract some data and you have to use Java language for this purpose. Let’s see how to quickly extract data from .xls or .xlsx files using Apache POI library.
Maven coordinates of the library(ies) can be found here: https://mvnrepository.com/artifact/org.apache.poi. Note that there are two types of excel spreadsheet formats and apache-poi project has two of its most important libraries to handle these data:
I registered in ChatGPT web page today. Here are my prompts and its responses. I’m not very creative, as you can see. Perhaps I don’t have enough faith in its capabilities to expect more than from a better search engine.
Images in today’s blog post are generated using http://bing.com/images/create
Generate blogpost about chat gpt written by a programmer about capabibities and risks related with AI usage when programming.
Notes about asynchronous programing in Dart. In this article I test and learn about two variants of writing asynchronous code in Dart: async/await and Future-based.