/**
 * Alipay.com Inc.
 * Copyright (c) 2004-2012 All Rights Reserved.
 */
package com.alipay.zdal.client.util;

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

import org.apache.log4j.Logger;

/**
 * ThreadLocal Context
 * @author ����
 * @version $Id: ThreadLocalMap.java, v 0.1 2014-1-6 ����05:15:36 Exp $
 */
public class ThreadLocalMap {
    private static final Logger                             log           = Logger
                                                                              .getLogger(ThreadLocalMap.class);
    protected final static ThreadLocal<Map<Object, Object>> threadContext = new MapThreadLocal();

    private ThreadLocalMap() {
    };

    public static void put(Object key, Object value) {
        getContextMap().put(key, value);
    }

    public static Object remove(Object key) {
        return getContextMap().remove(key);
    }

    public static Object get(Object key) {
        return getContextMap().get(key);
    }

    public static boolean containsKey(Object key) {
        return getContextMap().containsKey(key);
    }

    private static class MapThreadLocal extends ThreadLocal<Map<Object, Object>> {
        protected Map<Object, Object> initialValue() {
            return new HashMap<Object, Object>() {

                private static final long serialVersionUID = 3637958959138295593L;

                public Object put(Object key, Object value) {
                    if (log.isDebugEnabled()) {
                        if (containsKey(key)) {
                            log.debug("Overwritten attribute to thread context: " + key + " = "
                                      + value);
                        } else {
                            log.debug("Added attribute to thread context: " + key + " = " + value);
                        }
                    }

                    return super.put(key, value);
                }
            };
        }
    }

    /**
     * ȡ��thread context Map��ʵ����
     *
     * @return thread context Map��ʵ��
     */
    protected static Map<Object, Object> getContextMap() {
        return (Map<Object, Object>) threadContext.get();
    }

    /**
     * �����߳����б�holdס�Ķ����Ա����ã�
     */

    public static void reset() {
        getContextMap().clear();
    }
}