org.h2.util.SmallLRUCache Maven / Gradle / Ivy
/*
* Copyright 2004-2019 H2 Group. Multiple-Licensed under the MPL 2.0,
* and the EPL 1.0 (https://h2database.com/html/license.html).
* Initial Developer: H2 Group
*/
package org.h2.util;
import java.util.LinkedHashMap;
import java.util.Map;
/**
* This class implements a small LRU object cache.
*
* @param the key
* @param the value
*/
public class SmallLRUCache extends LinkedHashMap {
private static final long serialVersionUID = 1L;
private int size;
private SmallLRUCache(int size) {
super(size, (float) 0.75, true);
this.size = size;
}
/**
* Create a new object with all elements of the given collection.
*
* @param the key type
* @param the value type
* @param size the number of elements
* @return the object
*/
public static SmallLRUCache newInstance(int size) {
return new SmallLRUCache<>(size);
}
public void setMaxSize(int size) {
this.size = size;
}
@Override
protected boolean removeEldestEntry(Map.Entry eldest) {
return size() > size;
}
}