Decompilers do have some uses. They should not , however , be used to analyse malware (Those are all separate links, and all seem to endorse JD-GUI. One even claims it's the "best")
For what it's worth, if you do find yourself with legitimate cause to use a decompiler, I'd recommend CFR or Procyon. If you intend to analyse malware, my recommendation would be that you use a disassembler, such as Krakatau
(Adding to) The decompiler's output
JD-web isn't a thing any more, so I can't lead with rickroll via decompiler
| Escape sequences | JavaP* |
| Playing with names |
The decompiler itself
| Inner classes | Fernflower, CFR, JD-GUI, |
| goto_w | JD-GUI, |
| jsr_w | JD-GUI, |
| Synthetic members | JD-GUI, Procyon |
| Going backwards! | JD-GUI |