Java实现一个简单的内存缓存类
发布时间:2020-12-15 03:17:31 所属栏目:Java 来源:网络整理
导读:今天PHP站长网 52php.cn把收集自互联网的代码分享给大家,仅供参考。 import java.util.Collections;import java.util.HashMap;import java.util.Map;import java.util.concurrent.ExecutorService;import java.util.conc
以下代码由PHP站长网 52php.cn收集自互联网 现在PHP站长网小编把它分享给大家,仅供参考 import java.util.Collections; import java.util.HashMap; import java.util.Map; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.TimeUnit; public class SimpleCache<T> { private final Map<String,T> m_objects; private final Map<String,Long> m_expiredObjects; private final long m_lExpireTime; private final ExecutorService m_executor; public SimpleCache() { this(500); } public SimpleCache(final int nExpireTime) { m_objects = Collections.synchronizedMap(new HashMap<String,T>()); m_expiredObjects = Collections.synchronizedMap(new HashMap<String,Long>()); m_lExpireTime = nExpireTime; m_executor = Executors.newFixedThreadPool(256); Executors.newScheduledThreadPool(5).scheduleWithFixedDelay(RemoveExpiredObjects(),m_lExpireTime / 2,m_lExpireTime,TimeUnit.SECONDS); } private final Runnable RemoveExpiredObjects() { return new Runnable() { public void run() { for (final String name : m_expiredObjects.keySet()) { if (System.currentTimeMillis() > m_expiredObjects.get(name)) { m_executor.execute(CreateRemoveRunnable(name)); } } } }; } private final Runnable CreateRemoveRunnable(final String name) { return new Runnable() { public void run() { m_objects.remove(name); m_expiredObjects.remove(name); } }; } public long GetExpireTime() { return m_lExpireTime; } public void Put(final String name,final T obj) { Put(name,obj,m_lExpireTime); } public void Put(final String name,final T obj,final long expireTime) { m_objects.put(name,obj); m_expiredObjects.put(name,System.currentTimeMillis() + expireTime * 1000); } public T Get(final String name) { final Long expireTime = m_expiredObjects.get(name); if (expireTime == null) return null; if (System.currentTimeMillis() > expireTime) { m_executor.execute(CreateRemoveRunnable(name)); return null; } return m_objects.get(name); } @SuppressWarnings("unchecked") public <R extends T> R Get(final String name,final Class<R> type) { return (R) Get(name); } } 以上内容由PHP站长网【52php.cn】收集整理供大家参考研究 如果以上内容对您有帮助,欢迎收藏、点赞、推荐、分享。 (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |