private static Method getMethod(Class<?> bootstrapClassLoader, String methodName, Class<?>... parameterTypes) {
        try {
            Method declaredMethod = bootstrapClassLoader.getDeclaredMethod(methodName, parameterTypes);
            declaredMethod.setAccessible(true);
            return declaredMethod;
        } catch (NoSuchMethodException e) {
            throw new IllegalStateException(methodName + " not found Caused by:" + e.getMessage(), e);
        }

    }
for ibm j9 jvm

@author Woonduk Kang(emeroad)
agent-module/bootstraps/bootstrap-core/src/main/java/com/navercorp/pinpoint/bootstrap/classloader/J9BootLoader.java