Java tutorial
//package com.java2s; import java.util.Map; public class Main { private static final ThreadLocal<Map<Object, Object>> LOCAL_CACHE = new ThreadLocal<Map<Object, Object>>(); public static final boolean containsKey(Object key) { Map<Object, Object> cache = LOCAL_CACHE.get(); return cache != null && cache.containsKey(key); } public static final Object get(Object key) { Map<Object, Object> cache = LOCAL_CACHE.get(); return cache == null ? null : cache.get(key); } }