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Dahua ICC Open API SDK for Java

There is a newer version: 1.0.13.7

package com.dahuatech.hutool.core.map;

import java.util.LinkedHashMap;

/**
 * 固定大小的{@link LinkedHashMap} 实现
 *
 * @author looly
 * @param  键类型
 * @param  值类型
 */
public class FixedLinkedHashMap extends LinkedHashMap {
  private static final long serialVersionUID = -629171177321416095L;

  /** 容量，超过此容量自动删除末尾元素 */
  private int capacity;

  /**
   * 构造
   *
   * @param capacity 容量，实际初始容量比容量大1
   */
  public FixedLinkedHashMap(int capacity) {
    super(capacity + 1, 1.0f, true);
    this.capacity = capacity;
  }

  /**
   * 获取容量
   *
   * @return 容量
   */
  public int getCapacity() {
    return this.capacity;
  }

  /**
   * 设置容量
   *
   * @param capacity 容量
   */
  public void setCapacity(int capacity) {
    this.capacity = capacity;
  }

  @Override
  protected boolean removeEldestEntry(java.util.Map.Entry eldest) {
    // 当链表元素大于容量时，移除最老（最久未被使用）的元素
    return size() > this.capacity;
  }
}