核心緩存對象。 package com.aranin.spring.aop;import java.util.Date;
import java.util.LinkedHashMap;
import java.util.Map;public class MyCache {private LinkedHashMap<String, Object> cacheMap = new LinkedHashMap<String, Object>();private LinkedHashMap<String, Date> timeStampMap = new LinkedHashMap<String, Date>();/*** defines the max size of hashmap*/private long maxsize = 10; //should come from properties file or some configuration/*** how long the object should be stored before it is evicted from cache*/private long objectLifeTime = 10000;private boolean lock = false;public LinkedHashMap<String, Object> getCacheMap() {return cacheMap;}public void setCacheMap(LinkedHashMap<String, Object> cacheMap) {this.cacheMap = cacheMap;}public LinkedHashMap<String, Date> getTimeStampMap() {return timeStampMap;}public void setTimeStampMap(LinkedHashMap<String, Date> timeStampMap) {this.timeStampMap = timeStampMap;}public long getMaxsize() {return maxsize;}public void setMaxsize(long maxsize) {this.maxsize = maxsize;}public long getObjectLifeTime() {return objectLifeTime;}public void setObjectLifeTime(long objectLifeTime) {this.objectLifeTime = objectLifeTime;}public boolean isLock() {return lock;}public void setLock(boolean lock) {this.lock = lock;}/*** This method is used to retrive the object from cache* @param key* @return*/public Object get(String key){return this.getCacheMap().get(key);}/*** this method is used for putting an object in cache* @param key* @param object*/public void put(String key, Object object){//get the curr dateDate date = new Date(System.currentTimeMillis());//set object in cacheMapthis.getCacheMap().put(key,object);//put timestamp in cachethis.getTimeStampMap().put(key, date);}public void delete(String key){this.getCacheMap().remove(key);this.getTimeStampMap().remove(key);}public void clearAll(){this.setCacheMap(new LinkedHashMap<String, Object>());this.setTimeStampMap(new LinkedHashMap<String, Date>());}/*** remove last 2 entries* not worried about object life time* this is just an example*/public void resize(){System.out.println("inside resize");long size = this.getCacheMap().size();System.out.println("size + " + size);if(size == this.getMaxsize()){System.out.println("max size has reached");Map.Entry<String, Date> firstEntry = this.getTimeStampMap().entrySet().iterator().next();System.out.println("removing : " + firstEntry.getKey() + " value : " + firstEntry.getValue());this.timeStampMap.remove(firstEntry.getKey());Map.Entry<String, Object> firstCEntry = this.getCacheMap().entrySet().iterator().next();System.out.println("removing : " + firstCEntry.getKey() + " value : " + firstCEntry.getValue());this.cacheMap.remove(firstCEntry.getKey());}System.out.println("leaving resize with size : " + this.getCacheMap().size());}
}
