Nothing comes close to guava in quality. More on reddit.com

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Hands down IntelliJ. Everything else is garbage. I worked years with eclipse, netbeans and all the flavors of them and they all suck. IntelliJ is not perfect by any means, but the others are so bad, that IntelliJ looks like alien technology compared to them. More on reddit.com

Start with notepad++ if your teacher asks you to. You will understand how to manage your project, what is a classpath, what does a compilation step do, etc. Many of those things are automatically handled by advanced IDE, and if you skip the Notepad step, you might just assume that stuff somehow works under the hood, but not really understand how any of that works. More on reddit.com