It depends on what you are trying to do. Are you trying to look at the code and/or modify it to fit your needs? Are you simply looking for a free IDE?<p>Here is what I used 10 years ago when I was still doing Java.<p>Open Source IDE
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Netbeans IDE -> Loved the UI
Eclipse -> My team at Amazon used this and it was great<p>Free to Use (Closed-Source)
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IntelliJ IDEA Community Edition<p>Open Source Editor
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Visual Studio Code - If you don't care about IDE related features and just want an Editor<p>I don't have any background in C/C++ so I don't have any recommendations.<p>Hope this helps!
There’s still Eclipse. I prefer IntelliJ by a lot but it actually does work for Java although my experience is that installing a plug in is like Russian Roulette and that anything that isn’t the stock configuration could die of pluginitis.