Groovy LRU cache backed by LinkedHashMap

class LruCache<K, V> extends LinkedHashMap<K, V> {
    private final int maxSize
    LruCache(int maxSize) {
        super(16, 0.75f, true)
        this.maxSize = maxSize
    }
    @Override
    protected boolean removeEldestEntry(Map.Entry<K, V> eldest) {
        size() > maxSize
    }
}

def cache = new LruCache<String, Integer>(2)
cache.put('a', 1)
cache.put('b', 2)
assert cache.get('a') == 1
cache.put('c', 3)
println cache.keySet()