Java Bytecode and JVMTI Examples

A lot of my research has involved Java bytecode instrumentation with ASM and more recently, also JVMTI development. For instance, with VMVM, we instrumented bytecode to enable efficient java class reinitialization. With Phosphor, we instrumented bytecode to track metadata with every single variable, enabling performant and portable dynamic taint tracking. In ElectricTest, we combined bytecode instrumentation with JVMTI to efficiently detect data dependencies between test cases running within the same JVM. As I built each of these projects, I leaned heavily on code snippets that I found across the internet – while I had done a lot of Java development before starting these projects, I’d done nothing with bytecode instrumentation. I found it particularly difficult to find examples of how to use JVMTI (aside from the basic man-pages, and a few excellent blog posts by Kelly O’Hair). This archive consists of a number of examples on JVMTI and byte code rewriting