import java.util.List;

import net.sf.ehcache.Cache;
import net.sf.ehcache.CacheManager;
import net.sf.ehcache.Element;

/**
* <h5>描述:缓存管理类</h5>
*/
public class EhcacheService {

private static final String CACHE_NAME = "sysCache";
private static final String EHCACHE_CONFIG_NAME = "ehcache.xml";
private static CacheManager cacheManager;

static {
    String classesPath = getClassesPath();
    cacheManager =  CacheManager.create(classesPath + EHCACHE_CONFIG_NAME);

//      EhcacheService.putObjectCache(CACHE_NAME, "key01", 1000);
//      EhcacheService.putObjectCache(CACHE_NAME, "key02", "abc");
//      EhcacheService.putObjectCache(CACHE_NAME, "key03", 3.1415);
//      EhcacheService.putObjectCache(CACHE_NAME, "key04", "哈哈");
//      EhcacheService.putObjectCache(CACHE_NAME, "key05", "{\"id\":100}");
}

/**
 * @功能描述：   添加一个缓存到指定的缓存中
 * @param cache_name 配置文件中缓存的name
 * @param key 键
 * @param value 缓存值
 */
public synchronized static void putObjectCache(String cache_name, String key, Object value) {
    Cache cache = getCache(cache_name);
    if (null != cache) {
        cache.remove(key);
        Element elem = new Element(key, value);
        cache.put(elem);
    }
}

/**
 * @功能描述：   从指定的缓存中获取一个缓存数据的值
 * @param cache_name 配置文件中缓存的name
 * @param key 键
 * @return
 */
public static Object getObjectCache(String cache_name, String key) {
    Cache cache = getCache(cache_name);
    if (null != cache) {
        Element element = cache.get(key);
        // isExpired(Element element) 检查缓存是否过期
        if (element != null && !cache.isExpired(element)) {
            return element.getObjectValue();
        }
    }
    return null;
}

/**
 * <h5>功能:清空指定缓存的所有信息</h5>
 * @param cache_name 配置文件中缓存的name
 */
public static void removeCache(String cache_name){
    Cache cache = getCache(cache_name);
    cache.removeAll();
}

/**
 * <h5>功能:清空指定缓存的指定信息</h5>
 * @param cache_name 配置文件中缓存的name
 * @param key 键
 * @return boolean 是否移除成功
 */
public static boolean removeCache(String cache_name, String key){
    Cache cache = getCache(cache_name);
    return cache.remove(key);
}

/**
 * 停止缓存管理器
 */
public static void shutdown() {
    if (null!= cacheManager)
        cacheManager.shutdown();
}

// ==================== private method ====================

/**
 * @功能描述：   获取 classes 文件夹路径
 * @return classes绝对路径
 */
private static String getClassesPath(){
    String classesPath=Thread.currentThread().getContextClassLoader().getResource("").getPath();
    return classesPath;
}

/**
 * @功能描述：   获取指定名称的缓存
 * @param cache_name 配置文件中缓存的name
 * @return Cache 缓存
 */
private static Cache getCache(String cache_name) {
    return cacheManager.getCache(cache_name);
}

public static void main(String[] args) {
    System.out.println(Thread.currentThread().getContextClassLoader().getResource("").getPath().substring(1));//user.dir指定了当前的路径

    EhcacheService.putObjectCache(CACHE_NAME, "key01", 1000);
    EhcacheService.putObjectCache(CACHE_NAME, "key02", "abc");
    EhcacheService.putObjectCache(CACHE_NAME, "key03", 3.1415);
    EhcacheService.putObjectCache(CACHE_NAME, "key04", "哈哈");
    EhcacheService.putObjectCache(CACHE_NAME, "key05", "{\"id\":100}");

    EhcacheService.putObjectCache(CACHE_NAME, "key04", "Hello World");

//      removeCache(CACHE_NAME);
//      removeCache(CACHE_NAME, "key05");
    Cache demoCache = cacheManager.getCache(CACHE_NAME);
    if (null != demoCache) {
        List<?> demoList=demoCache.getKeys();
        for(Object myKey:demoList){
            Element myElement=demoCache.get(myKey);
            System.out.println(myKey+"|"+myElement.getObjectValue());
        }
    }
    EhcacheService.putObjectCache(CACHE_NAME, "key03", 3.1666);
    System.out.println("---------"+EhcacheService.getObjectCache(CACHE_NAME, "key03"));

    System.exit(0);
}
}