import java.util.*; 

 //Description: 管理緩存 

 //可擴展的功能：當chche到內(nèi)存溢出時必須清除掉最早期的一些緩存對象，這就要求對每個緩存對象保存創(chuàng)建時間 

public class CacheManager { 
 private static HashMap cacheMap = new HashMap(); 

 //單實例構(gòu)造方法 
 private CacheManager() { 
  super(); 
 } 
 //獲取布爾值的緩存 
 public static boolean getSimpleFlag(String key){ 
  try{ 
   return (Boolean) cacheMap.get(key); 
  }catch(NullPointerException e){ 
   return false; 
  } 
 } 
 public static long getServerStartdt(String key){ 
  try { 
   return (Long)cacheMap.get(key); 
  } catch (Exception ex) { 
   return 0; 
  } 
 } 
 //設(shè)置布爾值的緩存 
 public synchronized static boolean setSimpleFlag(String key,boolean flag){ 
  if (flag && getSimpleFlag(key)) {//假如為真不允許被覆蓋 
   return false; 
  }else{ 
   cacheMap.put(key, flag); 
   return true; 
  } 
 } 
 public synchronized static boolean setSimpleFlag(String key,long serverbegrundt){ 
  if (cacheMap.get(key) == null) { 
   cacheMap.put(key,serverbegrundt); 
   return true; 
  }else{ 
   return false; 
  } 
 } 


 //得到緩存。同步靜態(tài)方法 
 private synchronized static Cache getCache(String key) { 
  return (Cache) cacheMap.get(key); 
 } 

 //判斷是否存在一個緩存 
 private synchronized static boolean hasCache(String key) { 
  return cacheMap.containsKey(key); 
 } 

 //清除所有緩存 
 public synchronized static void clearAll() { 
  cacheMap.clear(); 
 } 

 //清除某一類特定緩存,通過遍歷HASHMAP下的所有對象，來判斷它的KEY與傳入的TYPE是否匹配 
 public synchronized static void clearAll(String type) { 
  Iterator i = cacheMap.entrySet().iterator(); 
  String key; 
  ArrayList arr = new ArrayList(); 
  try { 
   while (i.hasNext()) { 
    java.util.Map.Entry entry = (java.util.Map.Entry) i.next(); 
    key = (String) entry.getKey(); 
    if (key.startsWith(type)) { //如果匹配則刪除掉 
     arr.add(key); 
    } 
   } 
   for (int k = 0; k < arr.size(); k++) { 
    clearOnly(arr.get(k)); 
   } 
  } catch (Exception ex) { 
   ex.printStackTrace(); 
  } 
 } 

 //清除指定的緩存 
 public synchronized static void clearOnly(String key) { 
  cacheMap.remove(key); 
 } 

 //載入緩存 
 public synchronized static void putCache(String key, Cache obj) { 
  cacheMap.put(key, obj); 
 } 

 //獲取緩存信息 
 public static Cache getCacheInfo(String key) { 

  if (hasCache(key)) { 
   Cache cache = getCache(key); 
   if (cacheExpired(cache)) { //調(diào)用判斷是否終止方法 
    cache.setExpired(true); 
   } 
   return cache; 
  }else 
   return null; 
 } 

 //載入緩存信息 
 public static void putCacheInfo(String key, Cache obj, long dt,boolean expired) { 
  Cache cache = new Cache(); 
  cache.setKey(key); 
  cache.setTimeOut(dt + System.currentTimeMillis()); //設(shè)置多久后更新緩存 
  cache.setValue(obj); 
  cache.setExpired(expired); //緩存默認載入時，終止狀態(tài)為FALSE 
  cacheMap.put(key, cache); 
 } 
 //重寫載入緩存信息方法 
 public static void putCacheInfo(String key,Cache obj,long dt){ 
  Cache cache = new Cache(); 
  cache.setKey(key); 
  cache.setTimeOut(dt+System.currentTimeMillis()); 
  cache.setValue(obj); 
  cache.setExpired(false); 
  cacheMap.put(key,cache); 
 } 

 //判斷緩存是否終止 
 public static boolean cacheExpired(Cache cache) { 
  if (null == cache) { //傳入的緩存不存在 
   return false; 
  } 
  long nowDt = System.currentTimeMillis(); //系統(tǒng)當前的毫秒數(shù) 
  long cacheDt = cache.getTimeOut(); //緩存內(nèi)的過期毫秒數(shù) 
  if (cacheDt <= 0||cacheDt>nowDt) { //過期時間小于等于零時,或者過期時間大于當前時間時，則為FALSE 
   return false; 
  } else { //大于過期時間 即過期 
   return true; 
  } 
 } 

 //獲取緩存中的大小 
 public static int getCacheSize() { 
  return cacheMap.size(); 
 } 

 //獲取指定的類型的大小 
 public static int getCacheSize(String type) { 
  int k = 0; 
  Iterator i = cacheMap.entrySet().iterator(); 
  String key; 
  try { 
   while (i.hasNext()) { 
    java.util.Map.Entry entry = (java.util.Map.Entry) i.next(); 
    key = (String) entry.getKey(); 
    if (key.indexOf(type) != -1) { //如果匹配則刪除掉 
     k++; 
    } 
   } 
  } catch (Exception ex) { 
   ex.printStackTrace(); 
  } 

  return k; 
 } 

 //獲取緩存對象中的所有鍵值名稱 
 public static ArrayList getCacheAllkey() { 
  ArrayList a = new ArrayList(); 
  try { 
   Iterator i = cacheMap.entrySet().iterator(); 
   while (i.hasNext()) { 
    java.util.Map.Entry entry = (java.util.Map.Entry) i.next(); 
    a.add((String) entry.getKey()); 
   } 
  } catch (Exception ex) {} finally { 
   return a; 
  } 
 } 

 //獲取緩存對象中指定類型 的鍵值名稱 
 public static ArrayList getCacheListkey(String type) { 
  ArrayList a = new ArrayList(); 
  String key; 
  try { 
   Iterator i = cacheMap.entrySet().iterator(); 
   while (i.hasNext()) { 
    java.util.Map.Entry entry = (java.util.Map.Entry) i.next(); 
    key = (String) entry.getKey(); 
    if (key.indexOf(type) != -1) { 
     a.add(key); 
    } 
   } 
  } catch (Exception ex) {} finally { 
   return a; 
  } 
 } 

} 


package lhm.hcy.guge.frameset.cache; 

public class Cache { 
  private String key;//緩存ID 
  private Object value;//緩存數(shù)據(jù) 
  private long timeOut;//更新時間 
  private boolean expired; //是否終止 
  public Cache() { 
    super(); 
  } 

  public Cache(String key, Object value, long timeOut, boolean expired) { 
    this.key = key; 
    this.value = value; 
    this.timeOut = timeOut; 
    this.expired = expired; 
  } 

  public String getKey() { 
    return key; 
  } 

  public long getTimeOut() { 
    return timeOut; 
  } 

  public Object getValue() { 
    return value; 
  } 

  public void setKey(String string) { 
    key = string; 
  } 

  public void setTimeOut(long l) { 
    timeOut = l; 
  } 

  public void setValue(Object object) { 
    value = object; 
  } 

  public boolean isExpired() { 
    return expired; 
  } 

  public void setExpired(boolean b) { 
    expired = b; 
  } 
} 

//測試類， 
class Test { 
 public static void main(String[] args) { 
  System.out.println(CacheManager.getSimpleFlag("alksd")); 
//  CacheManager.putCache("abc", new Cache()); 
//  CacheManager.putCache("def", new Cache()); 
//  CacheManager.putCache("ccc", new Cache()); 
//  CacheManager.clearOnly(""); 
//  Cache c = new Cache(); 
//  for (int i = 0; i < 10; i++) { 
//   CacheManager.putCache("" + i, c); 
//  } 
//  CacheManager.putCache("aaaaaaaa", c); 
//  CacheManager.putCache("abchcy;alskd", c); 
//  CacheManager.putCache("cccccccc", c); 
//  CacheManager.putCache("abcoqiwhcy", c); 
//  System.out.println("刪除前的大小："+CacheManager.getCacheSize()); 
//  CacheManager.getCacheAllkey(); 
//  CacheManager.clearAll("aaaa"); 
//  System.out.println("刪除后的大?。?+CacheManager.getCacheSize()); 
//  CacheManager.getCacheAllkey(); 


 } 
}