MemCache.java

package czd.lib.cache;

import java.lang.ref.SoftReference;
import java.util.concurrent.ConcurrentHashMap;

/**
 * Created with IntelliJ IDEA.
 * User: chenzhidong
 * Date: 13-12-30
 * Time: 上午11:57
 */
public class MemCache implements CacheI<Object> {
	protected static MemCache instance;
	protected ConcurrentHashMap<String,SoftReference<Object>> mem;

	public MemCache() {
		mem = new ConcurrentHashMap<String,SoftReference<Object>>();
	}

	public static MemCache getInstance() {
		if (instance == null)
			instance = new MemCache();
		return instance;
	}

	@Override
	public boolean save(String key, Object value) {
		mem.put(genKey(key), new SoftReference<Object>(value));
		return true;
	}

	@Override
	public boolean exists(String key) {
		return mem.containsKey(genKey(key));
	}

	@Override
	public Object get(String key) {
		SoftReference<Object> softref = mem.get(genKey(key));
		if (softref != null)
			return softref.get();
		return null;
	}

	@Override
	public boolean delete(String key) {
		if (key.endsWith("*"))
		{
			for (String keys : mem.keySet())
				if (keys.startsWith(key))
					mem.remove(keys);
		}
		else
			mem.remove(genKey(key));
		return true;
	}

	@Override
	public long size() {
		return mem.size();
	}

	@Override
	public String getRealName(String key) {
		return genKey(key);
	}

	@Override
	public void clean() {
		mem.clear();
	}

	@Override
	public String genKey(String key) {
		return key;
	}

	@Override
	public long gettime(String key) {
		return 0L;
	}
}