@Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;

        DefaultServiceType that = (DefaultServiceType) o;

        return code == that.code;

    }
@author emeroad
@author netspider
@author Jongho Moon
commons/src/main/java/com/navercorp/pinpoint/common/trace/DefaultServiceType.java