Why is it so easy to decompile Java Code? [closed]

问题

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Closed 7 years ago.

So I've just realized how easy it is to decompile my Java code. I've been searching around the net and I can't seem to figure out WHY its so easy. Every time I google something like "Why can I decomilple .class files?" or "Why does Java decompile so easily", all I get is links to software that can easily deompile my code. So I turn to you StackOverflow: why is it that Java can be converted back to easlily readable source code while C++ and other languages aren't very friendly to decompiling?

Thanks

回答1:

Because Java byte-code is closer (more similar) to the source than assembly.

In particular, .class files include metadata for classnames, method names, field & parameter types, etc...
All a Java (or .Net) decompiler needs to do is look at the instructions in each method body, and turn them into the appropriate syntactic constructs.

By contrast, native languages like C++ do not include any metadata at all, so the decompiler needs to reconstruct everything.

回答2:

Java is compiled into an intermediate form, JVM bytecode, that retains a large amount of the information contained in the original Java code. A language like C++ compiles into assembly code, with looks a lot different from the original code, and is, therefore, harder to reverse.

来源：https://stackoverflow.com/questions/12450510/why-is-it-so-easy-to-decompile-java-code