简单的缓存设计

package com.buffer.clz;

import java.util.Map;
import java.util.WeakHashMap;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

public final class MyCache<K, V> {
	private final Lock lock = new ReentrantLock();
	private final int maxCapacity;
	private final Map<K,V> eden;
	private final Map<K,V> longterm;
	public MyCache(int maxCapacity) {
		super();
		this.maxCapacity = maxCapacity;
		this.eden = new ConcurrentHashMap<K,V>(maxCapacity);
		this.longterm =  new WeakHashMap<K,V>(maxCapacity);
	}
	
	public V get(K k){
		V v= this.eden.get(k);
		if(v == null){
			lock.lock();
			try {
				v = this.longterm.get(k);
			} catch (Exception e) {
				// TODO: handle exception
			}finally{
				lock.unlock();
			}
			if(v != null){
				this.eden.put(k, v);
			}
		}
		return v;
	}
	
	public void put(K k,V v){
		if(this.eden.size() >= maxCapacity){
			lock.lock();
			try {
				this.longterm.putAll(eden);
			} catch (Exception e) {
				// TODO: handle exception
			}finally{
				lock.unlock();
			}
			this.eden.clear();
		}
		this.eden.put(k, v);
	}
	
}