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Dahua ICC Open API SDK for Java

There is a newer version: 1.0.13.7

package com.dahuatech.hutool.cache.impl;

import java.io.Serializable;

/**
 * 缓存对象
 *
 * @author Looly
 * @param  Key类型
 * @param  Value类型
 */
public class CacheObj implements Serializable {
  private static final long serialVersionUID = 1L;

  protected final K key;
  protected final V obj;
  /** 访问次数 */
  protected long accessCount;
  /** 上次访问时间 */
  private long lastAccess;
  /** 对象存活时长，0表示永久存活 */
  private long ttl;

  /**
   * 构造
   *
   * @param key 键
   * @param obj 值
   * @param ttl 超时时长
   */
  protected CacheObj(K key, V obj, long ttl) {
    this.key = key;
    this.obj = obj;
    this.ttl = ttl;
    this.lastAccess = System.currentTimeMillis();
  }

  /**
   * 判断是否过期
   *
   * @return 是否过期
   */
  boolean isExpired() {
    if (this.ttl > 0) {
      final long expiredTime = this.lastAccess + this.ttl;
      // expiredTime > 0 杜绝Long类型溢出变负数问题，当当前时间超过过期时间，表示过期
      return expiredTime > 0 && expiredTime < System.currentTimeMillis();
    }
    return false;
  }

  /**
   * 获取值
   *
   * @param isUpdateLastAccess 是否更新最后访问时间
   * @return 获得对象
   * @since 4.0.10
   */
  V get(boolean isUpdateLastAccess) {
    if (isUpdateLastAccess) {
      lastAccess = System.currentTimeMillis();
    }
    accessCount++;
    return this.obj;
  }

  /**
   * 获取键
   *
   * @return 键
   * @since 4.0.10
   */
  public K getKey() {
    return this.key;
  }

  /**
   * 获取值
   *
   * @return 值
   * @since 4.0.10
   */
  public V getValue() {
    return this.obj;
  }

  @Override
  public String toString() {
    return "CacheObj [key="
        + key
        + ", obj="
        + obj
        + ", lastAccess="
        + lastAccess
        + ", accessCount="
        + accessCount
        + ", ttl="
        + ttl
        + "]";
  }
}