Many algorithms are expressed most concisely as tail-recursive methods. Compilers can automatically transform such methods into loops and thereby improve program performance, but this transformation is not required by the Java language specification, so not all JVMs will perform it. This means that tail-recursive methods in the Java language can result in unexpectedly large memory usage. This article demonstrates that dynamic compilation maintains the language's semantics while static compilation often doesn't. Learn why this matters and get a bit of code to help you determine whether your just-in-time (JIT) compiler can transform tail recursion on code while preserving semantics.

You inevitably spend some part of your week crunching code that you didn't write, and for which you may not have the source. This beginner's guide to opening up and locking down Java code walks you through the essentials of disassembling, decompiling, and obfuscating Java code, using examples from popular tools such as Mocha, HoseMocha, jmangle, and JODE.