How to use java.net.URLConnection to fire and handle HTTP requests

First a disclaimer beforehand: the posted code snippets are all basic examples. You'll need to handle trivial IOExceptions and RuntimeExceptions like NullPointerException, ArrayIndexOutOfBoundsException and consorts yourself. In case you're developing for Android instead of Java, note also that since introduction of API level 28, cleartext HTTP requests are disabled by default. You are encouraged

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