import java.util.LinkedHashMap;

import java.util.Map;

public class LruCache {

    private final Map<Object, Object> store;

    private static final int MAX = 1000;

    public LruCache() {

        this.store = new LinkedHashMap<Object, Object>() {

            private static final long serialVersionUID = -3834209229668463829L;;

            /**

             * 当满足一定条件时删除Map中的年老的Entry

             */

            @Override

            protected boolean removeEldestEntry(Entry<Object, Object> eldest) {

                return size() > MAX;

            }

        };

    }

    public void put(Object key, Object value) {

        synchronized (LruCache.class) {

            store.put(key, value);

        }

    }

    public Object get(Object key) {

        synchronized (LruCache.class) {

            return store.get(key);

        }

    }

}