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Dahua ICC Open API SDK for Java

There is a newer version: 1.0.13.10

package com.dahuatech.hutool.cache.file;

import com.dahuatech.hutool.cache.Cache;
import com.dahuatech.hutool.cache.impl.LFUCache;

import java.io.File;

/**
 * 使用LFU缓存文件，以解决频繁读取文件引起的性能问题
 *
 * @author Looly
 */
public class LFUFileCache extends AbstractFileCache {
  private static final long serialVersionUID = 1L;

  /**
   * 构造

   * 最大文件大小为缓存容量的一半

   * 默认无超时
   *
   * @param capacity 缓存容量
   */
  public LFUFileCache(int capacity) {
    this(capacity, capacity / 2, 0);
  }

  /**
   * 构造

   * 默认无超时
   *
   * @param capacity 缓存容量
   * @param maxFileSize 最大文件大小
   */
  public LFUFileCache(int capacity, int maxFileSize) {
    this(capacity, maxFileSize, 0);
  }

  /**
   * 构造
   *
   * @param capacity 缓存容量
   * @param maxFileSize 文件最大大小
   * @param timeout 默认超时时间，0表示无默认超时
   */
  public LFUFileCache(int capacity, int maxFileSize, long timeout) {
    super(capacity, maxFileSize, timeout);
  }

  @Override
  protected Cache initCache() {
    Cache cache =
        new LFUCache(this.capacity, this.timeout) {
          private static final long serialVersionUID = 1L;

          @Override
          public boolean isFull() {
            return LFUFileCache.this.usedSize > this.capacity;
          }

          @Override
          protected void onRemove(File key, byte[] cachedObject) {
            usedSize -= cachedObject.length;
          }
        };
    return cache;
  }
}