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Dahua ICC Open API SDK for Java

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package com.dahuatech.hutool.cache.impl;

import com.dahuatech.hutool.cache.GlobalPruneTimer;

import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.concurrent.ScheduledFuture;

/**
 * 定时缓存

 * 此缓存没有容量限制，对象只有在过期后才会被移除
 *
 * @author Looly
 * @param  键类型
 * @param  值类型
 */
public class TimedCache extends AbstractCache {
  private static final long serialVersionUID = 1L;

  /** 正在执行的定时任务 */
  private ScheduledFuture pruneJobFuture;

  /**
   * 构造
   *
   * @param timeout 超时（过期）时长，单位毫秒
   */
  public TimedCache(long timeout) {
    this(timeout, new HashMap>());
  }

  /**
   * 构造
   *
   * @param timeout 过期时长
   * @param map 存储缓存对象的map
   */
  public TimedCache(long timeout, Map> map) {
    this.capacity = 0;
    this.timeout = timeout;
    this.cacheMap = map;
  }

  // ---------------------------------------------------------------- prune
  /**
   * 清理过期对象
   *
   * @return 清理数
   */
  @Override
  protected int pruneCache() {
    int count = 0;
    Iterator> values = cacheMap.values().iterator();
    CacheObj co;
    while (values.hasNext()) {
      co = values.next();
      if (co.isExpired()) {
        values.remove();
        onRemove(co.key, co.obj);
        count++;
      }
    }
    return count;
  }

  // ---------------------------------------------------------------- auto prune
  /**
   * 定时清理
   *
   * @param delay 间隔时长，单位毫秒
   */
  public void schedulePrune(long delay) {
    this.pruneJobFuture =
        GlobalPruneTimer.INSTANCE.schedule(
            new Runnable() {
              @Override
              public void run() {
                prune();
              }
            },
            delay);
  }

  /** 取消定时清理 */
  public void cancelPruneSchedule() {
    if (null != pruneJobFuture) {
      pruneJobFuture.cancel(true);
    }
  }
}