sybn counter 计数器

• 简介
• 用法举例

简介

sybn counter 是一个多线程计数器, 此接口的两个实现 SybnCounterImpl 和 SybnCounterMapImpl 都是线程安全的. sybn counter 主要有以下功能:

• 以 Map<String, Long> 的形式维护一组支持inc操作的long型数据
• 记录任务的开始时间和任务进度,预估任务的剩余时间

用法举例

import cn.sybn.bean.counter.SybnCounter;
import cn.sybn.bean.counter.SybnCounterImpl;

SybnCounter count = new SybnCounterImpl();
count.setCount("aaa", 1);
count.incCount("aaa", 1);
long aaa = count.getCount("aaa"); // 2

count.setTotal(100);
count.incCurrent(10);
String log = count.toCountString(); // {progress:10/100( 10.00%), currentTime:1ms, remainTime:9ms, aaa:2}

• SybnCounterImpl 和 SybnCounterMapImpl 线程安全 SybnCounterSimpleImpl 线程不安全

    @Test
    public void mainTest() {
        // 测试并发 300 个线程同时写入
        final SybnCounterImpl c = new SybnCounterImpl();
        ExecutorService service = Executors.newFixedThreadPool(300);
        for (int i = 0; i < 1000; i++) {
        service.execute(new SybnCounterUtil.SybnCounterTestThread(c, i));
        }
        service.shutdown();
  
        try {
            service.awaitTermination(Long.MAX_VALUE, TimeUnit.DAYS);
            LogUtil.info(c);
        } catch (InterruptedException e) {
            Thread.currentThread().interrupt();
        } catch (Exception e) {
            LogUtil.getLogger().error("", e);
        }
  
        SybnCounterImpl c2 = new SybnCounterImpl(false);
        c2.setCount("a", 1);
        c2.incCount("a", 1);
        c2.clearCount("a");
        c2.incCount("a", 1);
        Assert.assertEquals(1, c2.getCount("a"));
    }
  

• SybnCounterMapAutoClearImpl 自动淘汰低频数据