spring 从3.x就提供了cache接口，spring默认实现的缓存是ehcache，spring的cache接口：
public interface Cache { String getName(); Object getNativeCache(); ValueWrapper get(Object key); <T> T get(Object key, Class<T> type); void put(Object key, Object value); void evict(Object key); void clear(); interface ValueWrapper { Object get(); }}?从spring的cache接口，我们可以看出spring的cache模型就是在内存中画一片内存区域出来，为这盘内存指定名称，在这盘内存区域中以key-value的方式存放数据，画个图来说明cache的存取方式，用户和部门的缓存，名称分别为DepartCache和UserCache
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1. 要使用spring的cache，首先要实现cacheManager， 可以参考spring对ehcache的实现，整合memcached的代码如下：
public class MemcachedCacheManager extends AbstractTransactionSupportingCacheManager { private ConcurrentMap<String, Cache> cacheMap = new ConcurrentHashMap<String, Cache>(); private Map<String, Integer> expireMap = new HashMap<String, Integer>(); //缓存的时间 private MemcachedClient memcachedClient; //xmemcached的客户端 public MemcachedCacheManager() { } @Override protected Collection<? extends Cache> loadCaches() { Collection<Cache> values = cacheMap.values(); return values; } @Override public Cache getCache(String name) { Cache cache = cacheMap.get(name); if (cache == null) { Integer expire = expireMap.get(name); if (expire == null) { expire = 0; expireMap.put(name, expire); } cache = new MemcachedCache(name, expire.intValue(), memcachedClient); cacheMap.put(name, cache); } return cache; } public void setMemcachedClient(MemcachedClient memcachedClient) { this.memcachedClient = memcachedClient; } public void setConfigMap(Map<String, Integer> configMap) { this.expireMap = configMap; }}?2. 接着看下MemcachedCache的实现，主要实现spring的cache接口
public class MemcachedCache implements Cache { private final String name; private final MemCache memCache; public MemcachedCache(String name, int expire, MemcachedClient memcachedClient) { this.name = name; this.memCache = new MemCache(name, expire, memcachedClient); } @Override public void clear() { memCache.clear(); } @Override public void evict(Object key) { memCache.delete(key.toString()); } @Override public ValueWrapper get(Object key) { ValueWrapper wrapper = null; Object value = memCache.get(key.toString()); if (value != null) { wrapper = new SimpleValueWrapper(value); } return wrapper; } @Override public String getName() { return this.name; } @Override public MemCache getNativeCache() { return this.memCache; } @Override public void put(Object key, Object value) { memCache.put(key.toString(), value); } @Override @SuppressWarnings("unchecked") public <T> T get(Object key, Class<T> type) { Object cacheValue = this.memCache.get(key.toString()); Object value = (cacheValue != null ? cacheValue : null); if (type != null && !type.isInstance(value)) { throw new IllegalStateException("Cached value is not of required type [" + type.getName() + "]: " + value); } return (T) value; }}?3. spring提供的这套缓存api其实就是底层缓存框架与应用程序之间的中间层转换，?这里还有一个类就是MemCache，这个类主要是对应memcached缓存的模型，spring的缓存只是提供了一套api，具体的实现要根据底层使用的什么缓存框架：
MemCache.java?
public class MemCache { private static Logger log = LoggerFactory.getLogger(MemCache.class); private Set<String> keySet = new HashSet<String>(); private final String name; private final int expire; private final MemcachedClient memcachedClient; public MemCache(String name, int expire, MemcachedClient memcachedClient) { this.name = name; this.expire = expire; this.memcachedClient = memcachedClient; } public Object get(String key) { Object value = null; try { key = this.getKey(key); value = memcachedClient.get(key); } catch (TimeoutException e) { log.warn("获取 Memcached 缓存超时", e); } catch (InterruptedException e) { log.warn("获取 Memcached 缓存被中断", e); } catch (MemcachedException e) { log.warn("获取 Memcached 缓存错误", e); } return value; } public void put(String key, Object value) { if (value == null) return; try { key = this.getKey(key); memcachedClient.setWithNoReply(key, expire, value); keySet.add(key); } catch (InterruptedException e) { log.warn("更新 Memcached 缓存被中断", e); } catch (MemcachedException e) { log.warn("更新 Memcached 缓存错误", e); } } public void clear() { for (String key : keySet) { try { memcachedClient.deleteWithNoReply(this.getKey(key)); } catch (InterruptedException e) { log.warn("删除 Memcached 缓存被中断", e); } catch (MemcachedException e) { log.warn("删除 Memcached 缓存错误", e); } } } public void delete(String key) { try { key = this.getKey(key); memcachedClient.deleteWithNoReply(key); } catch (InterruptedException e) { log.warn("删除 Memcached 缓存被中断", e); } catch (MemcachedException e) { log.warn("删除 Memcached 缓存错误", e); } } private String getKey(String key) { return name + "_" + key; }}?4. 在spring的配置文件中使用MemcachedCacheManager
<cache:annotation-driven cache-manager="cacheManager" proxy-target-class="true" /> <!-- 开启缓存 --><bean id="memcachedClientBuilder" class="net.rubyeye.xmemcached.XMemcachedClientBuilder"> <!-- 配置memcached的缓存服务器 --> <constructor-arg> <list> <bean class="java.net.InetSocketAddress"> <constructor-arg value="localhost" /> <constructor-arg value="11211" /> </bean> </list> </constructor-arg></bean><bean id="memcachedClient" factory-bean="memcachedClientBuilder" factory-method="build" destroy-method="shutdown" /><bean id="cacheManager" class="com.hqhop.framework.common.cache.memcached.MemcachedCacheManager"> <property name="memcachedClient" ref="memcachedClient" /> <!-- 配置缓存时间 --> <property name="configMap"> <map> <entry key="typeList" value="3600" /> <!-- key缓存对象名称 value缓存过期时间 --> </map> </property></bean>
?5. 到此为止，spring和memcached整合就完成了，spring的缓存还提供了很多的注解@Cachable，@cachePut.....