private boolean isHystrixOnClasspath() {
        try {
            Class.forName("com.netflix.hystrix.HystrixCommand");
            return true;
        } catch (ClassNotFoundException e) {
            return false;
        }
    }
Hystrix instrumentation

@author <a href=mailto:scienjus@gmail.com>ScienJus</a>
fault/fault-hystrix/src/main/java/com/alipay/sofa/rpc/hystrix/HystrixFilter.java