36 lines
984 B
Java
36 lines
984 B
Java
package com.moparisthebest.jdbc.util;
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import java.util.HashMap;
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import java.util.LinkedHashMap;
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import java.util.Map;
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import java.util.concurrent.ConcurrentHashMap;
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/**
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* Created by mopar on 6/19/17.
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*/
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public abstract class CacheUtil {
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public static <K, V> Map<K, V> getCache(final int maxEntries) {
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if (maxEntries > 0) { // we want a limited cache
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final float loadFactor = 0.75f; // default for HashMaps
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// if we set the initialCapacity this way, nothing should ever need re-sized
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final int initialCapacity = ((int) Math.ceil(maxEntries / loadFactor)) + 1;
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return new LinkedHashMap<K, V>(initialCapacity, loadFactor, true) {
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@Override
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protected boolean removeEldestEntry(final Map.Entry<K, V> eldest) {
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return size() > maxEntries;
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}
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};
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} else
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return new HashMap<K, V>();
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}
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public static <K, V> Map<K, V> getCache(final boolean threadSafe) {
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return threadSafe ?
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new ConcurrentHashMap<K, V>()
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:
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new HashMap<K, V>();
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}
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}
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