Java Code Examples for net.sf.ehcache.Cache#get()

public Element getElement(String channel, String key){
	Element result = null;
	long fr = System.currentTimeMillis();
	Cache cache = getCache(channel);
	if(null != cache){
		result = cache.get(key);
		if(null == result){
	    	if(ConfigTable.isDebug() && log.isWarnEnabled()){
	    		log.warn("[缓存不存在][cnannel:{}][key:{}][生存:-1/{}]",channel, key,cache.getCacheConfiguration().getTimeToLiveSeconds());
	    	}
			return null;
		}
		if(result.isExpired()){
	    	if(ConfigTable.isDebug() && log.isWarnEnabled()){
	    		log.warn("[缓存数据提取成功但已过期][耗时:{}][cnannel:{}][key:{}][命中:{}][生存:{}/{}]",System.currentTimeMillis()-fr,channel,key,result.getHitCount(),(System.currentTimeMillis() - result.getCreationTime())/1000,result.getTimeToLive());
	    	}
	    	result = null;
		}else{
			if(ConfigTable.isDebug() && log.isWarnEnabled()){
	    		log.warn("[缓存数据提取成功并有效][耗时:{}][cnannel:{}][key:{}][命中:{}][生存:{}/{}]",System.currentTimeMillis()-fr,channel,key,result.getHitCount(),(System.currentTimeMillis() - result.getCreationTime())/1000,result.getTimeToLive());
	    	}
		}
	}
	return result;
}
 

@Override
public RepeaterResult<Regress> getRegressWithCache(String name) {
    Cache cache = cacheManager.getCache("regressCache");
    // priority use of the cache data
    Element element = cache.get(name);
    Regress regress;
    if (element == null) {
        regress = getRegressInternal(name, 1);
        cache.put(new Element(name, regress));
    } else {
        regress = (Regress) element.getObjectValue();
    }
    return RepeaterResult.builder()
            .data(regress)
            .success(true)
            .message("operate success")
            .build();
}
 

@Around("execution(* org.packt.aop.transaction.dao.impl.EmployeeDaoImpl.getEmployees(..))")
public Object cacheMonitor(ProceedingJoinPoint joinPoint) throws Throwable  {
   logger.info("executing " + joinPoint.getSignature().getName());
   Cache cache = cacheManager.getCache("employeesCache");
  
   logger.info("cache detected is  " + cache.getName());
   logger.info("begin caching.....");
   String key = joinPoint.getSignature().getName();
   logger.info(key);
   if(cache.get(key) == null){
	   logger.info("caching new Object.....");
	   Object result = joinPoint.proceed();
	   cache.put(new Element(key, result)); 	   
	   return result;
   }else{
	   logger.info("getting cached Object.....");
	   return cache.get(key).getObjectValue();
   }
}
 

/**
 * Description: <br>
 * 
 * @author 王伟<br>
 * @taskId <br>
 * @param nodeName
 * @param type
 * @return <br>
 */
@SuppressWarnings("unchecked")
@Override
public <T> Map<String, T> getNode(final String nodeName, final Class<T> type) {
    Cache cache = getCache(nodeName);
    List<String> keys = cache.getKeysWithExpiryCheck();
    Map<String, T> cacheMap = new HashMap<String, T>();
    if (CollectionUtils.isNotEmpty(keys)) {
        for (String key : keys) {
            Element element = cache.get(key);
            Object value = (element != null ? element.getObjectValue() : null);
            if (value != null && type != null && !type.isInstance(value)) {
                throw new IllegalStateException(
                    "Cached value is not of required type [" + type.getName() + "]: " + value);
            }
            cacheMap.put(key, (T) value);
        }
    }
    return cacheMap;
}
 

public TableModel get( final DataCacheKey key ) {
  final Cache cache = this.cache;
  synchronized ( this ) {
    if ( cache == null ) {
      return null;
    }

    if ( cache.getStatus() != Status.STATUS_ALIVE ) {
      this.cache = null;
      return null;
    }
  }

  final Element element = cache.get( key );
  if ( element == null ) {
    return null;
  }
  return (TableModel) element.getObjectValue();
}
 

@Override
public void updateChannelAssignment(String ccid, BounceProxyInformation bpInfo) throws IllegalArgumentException {

    if (log.isTraceEnabled()) {
        log.trace("Update channel assignment for bounce proxy {} in cache {}", bpInfo.getId(), cacheName);
        tracePeers();
    }

    Cache cache = manager.getCache(cacheName);
    Element element = cache.get(bpInfo.getId());

    if (element == null) {
        throw new IllegalArgumentException("No bounce proxy with ID '" + bpInfo.getId() + "' exists");
    }

    BounceProxyRecord bpRecord = getBounceProxyRecordFromElement(element);
    bpRecord.addAssignedChannel(ccid);
    Element updatedElement = new Element(bpInfo.getId(), bpRecord);
    cache.put(updatedElement);
}
 

/**
 * 获取缓存记录
 * @param cacheName
 * @param key
 * @return
 */
public static Object get(String cacheName, String key) {
    Cache cache = getCache(cacheName);
    if (null == cache) {
        return null;
    }
    Element cacheElement = cache.get(key);
    if (null == cacheElement) {
        return null;
    }
    return cacheElement.getObjectValue();
}
 

/** Test.
 * @throws IOException e */
@Test
public void testCache() throws IOException {
	final String cacheName = "test 1";
	final CacheManager cacheManager = CacheManager.getInstance();
	cacheManager.addCache(cacheName);
	// test empty cache name in the cache keys link:
	// cacheManager.addCache("") does nothing, but cacheManager.addCache(new Cache("", ...)) works
	cacheManager.addCache(new Cache("", 1000, true, false, 10000, 10000, false, 10000));
	final String cacheName2 = "test 2";
	try {
		final Cache cache = cacheManager.getCache(cacheName);
		cache.put(new Element(1, Math.random()));
		cache.get(1);
		cache.get(0);
		cacheManager.addCache(cacheName2);
		final Cache cache2 = cacheManager.getCache(cacheName2);
		cache2.getCacheConfiguration().setOverflowToDisk(false);
		cache2.getCacheConfiguration().setEternal(true);
		cache2.getCacheConfiguration().setMaxElementsInMemory(0);

		// JavaInformations doit être réinstancié pour récupérer les caches
		final List<JavaInformations> javaInformationsList2 = Collections
				.singletonList(new JavaInformations(null, true));
		final HtmlReport htmlReport = new HtmlReport(collector, null, javaInformationsList2,
				Period.TOUT, writer);
		htmlReport.toHtml(null, null);
		assertNotEmptyAndClear(writer);
		setProperty(Parameter.SYSTEM_ACTIONS_ENABLED, "false");
		htmlReport.toHtml(null, null);
		assertNotEmptyAndClear(writer);
	} finally {
		setProperty(Parameter.SYSTEM_ACTIONS_ENABLED, null);
		cacheManager.removeCache(cacheName);
		cacheManager.removeCache(cacheName2);
	}
}
 

@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
    Cache cache = cacheManager.getCache("testCache");

    String objectKey = "dataKey";

    Element el = new Element(objectKey, "2");

    // EhcacheOperateElementInterceptor
    cache.put(el);

    // EhcacheOperateObjectInterceptor
    cache.get(objectKey);

    // EhcacheOperateAllInterceptor
    cache.putAll(Arrays.asList(new Element[] {el}));

    // EhcacheLockInterceptor
    try {
        boolean success = cache.tryReadLockOnKey(objectKey, 300);
    } catch (InterruptedException e) {
    } finally {
        cache.releaseReadLockOnKey(objectKey);
    }

    // EhcacheCacheNameInterceptor
    cacheManager.addCacheIfAbsent("testCache2");

    Cache cloneCache = cacheManager.getCache("testCache2");

    // EhcacheOperateElementInterceptor
    cloneCache.put(el);

    PrintWriter printWriter = resp.getWriter();
    printWriter.write("success");
    printWriter.flush();
    printWriter.close();
}
 

@Override
public BounceProxyRecord getBounceProxy(String bpId) throws IllegalArgumentException {

    if (log.isTraceEnabled()) {
        log.trace("Retrieving bounce proxy {} from cache {}", bpId, cacheName);
        tracePeers();
    }
    Cache cache = manager.getCache(cacheName);
    Element element = cache.get(bpId);

    if (element == null) {
        throw new IllegalArgumentException("No bounce proxy with ID '" + bpId + "' exists");
    }
    return getBounceProxyRecordFromElement(element);
}
 

@Override
public boolean containsBounceProxy(String bpId) {

    if (log.isTraceEnabled()) {
        log.trace("containsBounceProxy {} in cache {}", bpId, cacheName);
        tracePeers();
    }
    Cache cache = manager.getCache(cacheName);
    return cache.get(bpId) != null;
}
 

@Override
public Object getCache(String group, String key) {
    try {
        createIfMissing(group);
        Cache c = cacheManager.getCache(group);
        return c.get(key) == null ? null : c.get(key).getObjectValue();
    } catch (Exception e) {
        LogFilter.log(LOGGER, LogLevel.WARNING, "{}", e, e);
        return null;
    }
}
 

@Override
public Object get(String cacheName, Object key) {
	log.debug("  EhcacheService  get cacheName: [{}] , key: [{}]",cacheName,key);
	Cache cache = manager.getCache(cacheName);
	if (cache != null) {
		Element element = cache.get(key);
		if (element != null) {
			return element.getObjectValue();
		}
	}
	return null;
}
 

public static void main(String[] args) {
	try {

		// 创建一个CacheManager实例
		CacheManager manager = new CacheManager();
		// 增加一个cache
		manager.addCache("cardCache");
		// 获取所有cache名称
		String[] cacheNamesForManager = manager.getCacheNames();
		int iLen = cacheNamesForManager.length;
		System.out.println("缓存名称列表:----------------------------");
		for (int i = 0; i < iLen; i++) {
			System.out.println(cacheNamesForManager[i].toString());
		}

		// 获取cache对象
		Cache cache = manager.getCache("cardCache");
		// create
		Element element = new Element("username", "howsky");
		cache.put(element);

		// get
		Element element_get = cache.get("username");
		Object value = element_get.getObjectValue();
		System.out.println(value.toString());
		
		Element element_get2 = cache.get("username");
		System.out.println(element_get2==element_get);

		// update
		cache.put(new Element("username", "howsky.net"));
		// get
		Element element_new = cache.get("username");
		
		System.out.println(element_new==element_get);
		
		Object value_new = element_new.getObjectValue();
		System.out.println(value_new.toString());

		cache.remove("username");

		// 移除cache
		manager.removeCache("cardCache");

		// 关闭CacheManager
		manager.shutdown();

	} catch (Exception e) {

		System.out.println(e.getMessage());

	}
}
 

/**
 * 使用Ehcache默认配置(classpath下的ehcache.xml)获取单例的CacheManager实例
 */
@Test
public void operation() {
	CacheManager manager = CacheManager.newInstance("src/test/resources/ehcache/ehcache.xml");

	// 获得Cache的引用
	Cache cache = manager.getCache("users");

	// 将一个Element添加到Cache
	cache.put(new Element("key1", "value1"));

	// 获取Element，Element类支持序列化，所以下面两种方法都可以用
	Element element1 = cache.get("key1");
	// 获取非序列化的值
	System.out.println("key=" + element1.getObjectKey() + ", value=" + element1.getObjectValue());
	// 获取序列化的值
	System.out.println("key=" + element1.getKey() + ", value=" + element1.getValue());

	// 更新Cache中的Element
	cache.put(new Element("key1", "value2"));
	Element element2 = cache.get("key1");
	System.out.println("key=" + element2.getObjectKey() + ", value=" + element2.getObjectValue());

	// 获取Cache的元素数
	System.out.println("cache size:" + cache.getSize());

	// 获取MemoryStore的元素数
	System.out.println("MemoryStoreSize:" + cache.getMemoryStoreSize());

	// 获取DiskStore的元素数
	System.out.println("DiskStoreSize:" + cache.getDiskStoreSize());

	// 移除Element
	cache.remove("key1");
	System.out.println("cache size:" + cache.getSize());

	// 关闭当前CacheManager对象
	manager.shutdown();

	// 关闭CacheManager单例实例
	CacheManager.getInstance().shutdown();
}