package org.nutz.ioc.loader.cached;

import java.util.HashMap;
import java.util.Map;

import org.nutz.ioc.IocLoader;
import org.nutz.ioc.IocLoading;
import org.nutz.ioc.ObjectLoadException;
import org.nutz.ioc.meta.IocObject;

/**
 * 简单的带缓存的IocLoader <b/>仅对singleton == true的IocObject对象进行缓存,
 * 
 * @author wendal(wendal1985@gmail.com)
 * 
 */
public class CachedIocLoaderImpl implements CachedIocLoader {

    public static CachedIocLoaderImpl create(IocLoader proxyIocLoader) {
        return new CachedIocLoaderImpl(proxyIocLoader);
    }

    private IocLoader proxyIocLoader;

    private Map<String, IocObject> map;

    private CachedIocLoaderImpl(IocLoader proxyIocLoader) {
        this.proxyIocLoader = proxyIocLoader;
        this.map = new HashMap<String, IocObject>();
    }

    public void clear() {
        map.clear();
    }

    public String[] getName() {
        return proxyIocLoader.getName();
    }

    public boolean has(String name) {
        return proxyIocLoader.has(name);
    }

    public IocObject load(IocLoading loading, String name) throws ObjectLoadException {
        IocObject iocObject = map.get(name);
        if (iocObject == null) {
            iocObject = proxyIocLoader.load(loading, name);
            if (iocObject == null)
                return null;
            if (iocObject.isSingleton() && iocObject.getType() != null)
                map.put(name, iocObject);
        }
        return iocObject;
    }
    
    @Override
    public String toString() {
        return proxyIocLoader.toString();
    }
}