@Override
    public long getSpanYoungGCCollectionCount() {
        long current = getYoungGCCollectionCount();
        if (lastYoungGCCollectionCount == -1) {
            lastYoungGCCollectionCount = current;
            return 0;
        } else {
            long result = current - lastYoungGCCollectionCount;
            lastYoungGCCollectionCount = current;
            return result;
        }
    }
@author Robert HG (254963746@qq.com) on 9/15/15.
lts-core/src/main/java/com/github/ltsopensource/jvmmonitor/mbean/JVMGC.java