@Override
    public void addClassFileTransformer(ClassLoader classLoader, String targetClassName, String transformCallbackClass) {
        checkOpen();
        instrumentContext.addClassFileTransformer(classLoader, targetClassName, transformCallbackClass);
    }
@author Woonduk Kang(emeroad)
@author jaehong.kim
agent-module/profiler/src/main/java/com/navercorp/pinpoint/profiler/instrument/GuardInstrumentContext.java