How to use a SE API key

You came up with an idea of a Java app that deals with Stack Exchange. You discovered that they have an API so there's no need to scrape pages. You then found out that apps that don't have an API key get to make really few requests between two UTC midnights, so you went get a key.

But, one problem remains: How on earth are you going to use that key?

The .java file in this repository demonstrates just that by fetching general info about Stack Overflow with an API key.

---

Here's an overview of the workflow in that .java file (with "you" being "the program"):

• Step 1) You open a connection to https://api.stackexchange.com/2.2/info?site=stackoverflow&key=YOUR_API_KEY_HERE.
• Step 2) The API packs miscellaneous facts about Stack Overflow into a JSON object, GZIPs it, and sends it to you.
• Step 3) You unGZIP the JSON you just got and use it (in this case, by printing it to System.out).

You might notice a difference when reading the JSON. Without a key, the JSON looks like this (without all the whitespace of course, I added them for readability):

{
  "items": [
    {
      "new_active_users": 17,
      "total_users": 6451004,
      "badges_per_minute": 4.72,
      "total_badges": 20788919,
      "total_votes": 92571680,
      "total_comments": 63593718,
      "answers_per_minute": 4.67,
      "questions_per_minute": 2.94,
      "total_answers": 20573764,
      "total_accepted": 7043247,
      "total_unanswered": 3621881,
      "total_questions": 12949924,
      "api_revision": "2016.12.6.24026"
    }
  ],
  "has_more": false,
  "quota_max": 300,
  "quota_remaining": 240
}

With a key, it looks like this (note that quota_max went up by a lot):

{
  "items": [
    {
      "new_active_users": 17,
      "total_users": 6451004,
      "badges_per_minute": 4.72,
      "total_badges": 20788919,
      "total_votes": 92571680,
      "total_comments": 63593718,
      "answers_per_minute": 4.67,
      "questions_per_minute": 2.94,
      "total_answers": 20573764,
      "total_accepted": 7043247,
      "total_unanswered": 3621881,
      "total_questions": 12949924,
      "api_revision": "2016.12.6.24026"
    }
  ],
  "has_more": false,
  "quota_max": 10000,
  "quota_remaining": 9940
}