技術標籤：功能實現java快取

package com.ctid.dnc.monitor.business.cache;

import java.util.concurrent.ConcurrentHashMap;

public class SystemDataCache {

    private static SystemDataCache instance = null;

    private SystemDataCache() {
    }

    public static SystemDataCache getInstance() {
        if (
 
instance == null) {
            instance = new SystemDataCache();
        }
        return instance;
    }

    private static ConcurrentHashMap<String, Object> cache = new ConcurrentHashMap<>(30);

    public void putValue(String key, Object value) {
        cache.put(key, value);
    }

    public
 
 <T> T getValue(String key) {
        return (T) cache.get(key);
    }

    public Boolean exist(String key) {
        return cache.containsKey(key);
    }

    public void clear() {
        cache.clear();
    }
}