Map加锁操作小例子
所谓加锁，即对一些公用的资源操作的时候进行锁定，操作完之后释放，写个小例子：
[java][/java]
- package com.tycyjd.action;
- import java.util.HashMap;
- import java.util.Map;
- public class MyTest {
- private static Map<String, Object> map = new HashMap<String, Object>();
- private static Map<String, Object> preMap = new HashMap<String, Object>();
- // 加锁机制
- public static synchronized boolean setCartMap(Map<String, Object> checkMap) {
- preMap = map;
- System.out.println(“oldMap:” + map.toString());
- for (Map.Entry<String, Object> entry : checkMap.entrySet()) {
- if (null != map.get(entry.getKey())) {
- map = preMap;
- System.out.println(“newMap:” + map.toString());
- return false;
- } else {
- map.put(entry.getKey(), entry.getValue());
- }
- }
- System.out.println(“newMap:” + map.toString());
- // map.clear();
- return true;
- }
- }
