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/**
 * Copyright (c) 2013, impossibl.com
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *  * Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *  * Neither the name of impossibl.com nor the names of its contributors may
 *    be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 */
package com.impossibl.postgres.utils;

import java.util.LinkedHashMap;
import java.util.Map;
import java.util.function.Consumer;

public class CacheMap extends LinkedHashMap {

  private int maxSize;
  private Consumer> evictionHandler;

  public CacheMap(int maxSize, float loadFactor, boolean accessOrder) {
    super(maxSize + 1, loadFactor, accessOrder);
    this.maxSize = maxSize;
  }

  public CacheMap(int maxSize, float loadFactor, boolean accessOrder, Consumer> evictionHandler) {
    super(maxSize + 1, loadFactor, accessOrder);
    this.maxSize = maxSize;
    this.evictionHandler = evictionHandler;
  }

  @Override
  protected boolean removeEldestEntry(Map.Entry eldest) {
    if (size() > maxSize) {
      if (evictionHandler != null) {
        evictionHandler.accept(eldest);
      }
      return true;
    }
    else {
      return false;
    }
  }

}