CFR will decompile modern Java features - Java 8 lambdas (pre and post Java beta 103 changes), Java 7 String switches etc, but is written entirely in Java 6. [ http://www.benf.org/other/cfr/ ].
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ILSpy Alternatives for Mac
ILSpy is not available for Mac but there is one alternative that runs on macOS with similar functionality. The best Mac alternative is CFR, which is both free and Open Source. If that doesn't work for you, our users have ranked eight alternatives to ILSpy, but unfortunately only one of them is available for Mac. If you can't find an alternative you can try to remove all filters.
They are both decompilers, but ILSpy is for Microsoft MSIL used in C#/F#/VB &c., while CFR is for JVM ByteCodes, using in Java and a pile of other JVM languages ... so while they have the same theoretical "function", they don't overlap at all in actual use!