Until recently, you needed to use a Java decompiler and all of them were either unstable, obsolete, unfinished, or in the best case all of the above. And, if not, then they were commercial.The obsoleteness was typically proved by the fact that they can only decompile JDK 1.3 bytecode.The only so-so working solution was to take the.class file and pre-process it, so it becomes JDK 1.3 compatible, and then run Jad over it (one of those older, but better decompilers).But recently, a new wave of decompilers has forayed onto the market: Procyon, CFR, JD, Fernflower, Krakatau, Candle.Here's a list of decompilers presented on this site:CFRFree, no source-code available,Author: Lee BenfieldVery well-updated decompiler!
CFR is able to decompile modern Java features - Java 9 modules, Java 8 lambdas, Java 7 String switches etc.It'll even make a decent go of turning class files from other JVM langauges back into java!JDfree for non-commercial use only,Author: Emmanuel DupuyUpdated in 2015. Has its own visual interface and plugins to Eclipse and IntelliJ. Written in C, so very fast. Supports Java 5.Procyonopen-source,Author: Mike StrobelUpdated in 2015.
Handles language enhancements from Java 5 and beyond, up to Java 8, including:. Enum declarations. Enum and String switch statements. Local classes (both anonymous and named). Annotations.
How To Open Class Files
Java 8 Lambdas and method references (i.e., the:: operator). Java 7 is required to run.Fernfloweropen-source,Author: Egor UshakovUpdated in 2015. Very promising analytical Java decompiler, now becomes an integral part of IntelliJ 14. Supports Java up to version 6 (Annotations, generics, enums)JADgiven here only for historical reason.
Java Class Example Code
Free, no source-code available,Author: Pavel KouznetsovProbably, this is the most popular Java decompiler, but primarily of this age only. Written in C, so very fast.Outdated, unsupported and does not decompile correctly Java 5 and later.Need to know what traffic your competitors are generating? Check out my new service.