[jboss-jira] [JBoss JIRA] (JASSIST-165) VerifyError with addLocalVariable() and insertAfter() when the method body is in a try catch statement

VerifyError with addLocalVariable() and insertAfter() when the method body is in a try catch statement ------------------------------------------------------------------------------------------------------ Key: JASSIST-165 URL: https://issues.jboss.org/browse/JASSIST-165 Project: Javassist Issue Type: Bug Affects Versions: 3.16.1-GA Environment: JDK 1.6, javassist3.16.1_GA Reporter: Hua Zhang Assignee: Shigeru Chiba Priority: Blocker CtClass cc = pool.get(className); CtMethod theMethod = ...; cc.defrost(); theMethod.addLocalVariable("__t", pool.get("long")); theMethod.insertBefore("{long __t = System.nanoTime();}"); theMethod.insertAfter("{System.out.println(System.nanoTime() - __t);}"); cc.freeze(); byte[] classFile = cc.toBytecode(); swapper.reload(className, classFile); // swapper is javassist.util.HotSwapper This code snippet can work for the method which doesn't contain try catch statement. However, if the method likes this: public void method(...) { try { ...... } catch (Exception e) { } } Error thrown: Exception in thread "HotSwap" java.lang.VerifyError: verifier detected internal inconsistency or security problem It is because __t is not visible in insertAfter() in this case. If modify the statement "theMethod.insertAfter("{System.out.println(System.nanoTime() - __t);}");" to be "theMethod.insertAfter("{System.out.println(System.nanoTime());}");" ( it removes the reference to variable __t), the code can work properly. Note I use insertAfter(String), not insertAfter(String, true).