I've been trying to do this for the past few days, and I've followed this websites tutorials word by word, but for whatever reason, when I run the command gradlew setupDecompWorkspace with and without the --refresh-dependencies, it always ends in failure telling me that it cannot find my java decompiler, but I have installed JDK 7 and JRE 7 and I've edited the PATH variable with the correct directories and I DID NOT forget the semi-colans. I have restarted my PC twice, which did not fix the issue. I tried editing the PATH with the file it needs, I assume the javac.exe, but that still didn't work, so I changed the variable back. I'm running Windows 8 64-bit on an Alienware X51 PC. If you need any more info to help me, ask and I can supply it.

I've deleted all my files for this and started over twice now, including reinstalling JDK and JRE, just in case something went wrong with the downloads, but that wasn't the case.

OK, so I think I fixed it. Instead of having BOTH JRE and JDK variables in JAVA_HOME, I only put JDK, and that seemed to fix it. I think it has to do with both JRE and JDK having a /bin/java.exe because that's what the gradlew.bat was looking for with the variables. I don't know much about code, but in a logical sense that seems to be an issue, but I could be COMPLETELY wrong, so idk.