From 6c00f26e1364697d4a0b4e22107c87a4851c1ec9 Mon Sep 17 00:00:00 2001
From: jinyu <foxinmy@gmail.com>
Date: Fri, 22 Jul 2016 14:04:33 +0800
Subject: [PATCH] =?UTF-8?q?weixin4j-base:=E8=8E=B7=E5=8F=96cache=E6=97=B6?=
 =?UTF-8?q?=E5=8A=A0=E9=94=81=E5=A4=84=E7=90=86(via=20=E9=A3=8E=E8=BD=A6?=
 =?UTF-8?q?=E8=BD=A6)?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 CHANGE.md                                     |  4 +++-
 .../foxinmy/weixin4j/cache/CacheManager.java  | 21 ++++++++++++++++---
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/CHANGE.md b/CHANGE.md
index b1fe8e8c..3bffe1a7 100644
--- a/CHANGE.md
+++ b/CHANGE.md
@@ -735,4 +735,6 @@
   
 * 2016-07-22
 
-  + weixin4j-base:主要调整退款相关类与官网一致
\ No newline at end of file
+  + weixin4j-base:主要调整退款相关类与官网一致
+  
+  + weixin4j-base:获取cache时加锁处理(via 风车车)
\ No newline at end of file
diff --git a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/cache/CacheManager.java b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/cache/CacheManager.java
index 808bca27..ff9d9485 100644
--- a/weixin4j-base/src/main/java/com/foxinmy/weixin4j/cache/CacheManager.java
+++ b/weixin4j-base/src/main/java/com/foxinmy/weixin4j/cache/CacheManager.java
@@ -1,5 +1,8 @@
 package com.foxinmy.weixin4j.cache;
 
+import java.util.concurrent.TimeUnit;
+import java.util.concurrent.locks.ReentrantLock;
+
 import com.foxinmy.weixin4j.exception.WeixinException;
 
 /**
@@ -14,6 +17,7 @@ import com.foxinmy.weixin4j.exception.WeixinException;
 public class CacheManager<T extends Cacheable> {
 	protected final CacheCreator<T> cacheCreator;
 	protected final CacheStorager<T> cacheStorager;
+	private final ReentrantLock lock = new ReentrantLock();
 
 	public CacheManager(CacheCreator<T> cacheCreator,
 			CacheStorager<T> cacheStorager) {
@@ -30,9 +34,20 @@ public class CacheManager<T extends Cacheable> {
 	public T getCache() throws WeixinException {
 		String cacheKey = cacheCreator.key();
 		T cache = cacheStorager.lookup(cacheKey);
-		if (cache == null) {
-			cache = cacheCreator.create();
-			cacheStorager.caching(cacheKey, cache);
+		try {
+			if (cache == null && lock.tryLock(3, TimeUnit.SECONDS)) {
+				try {
+					cache = cacheStorager.lookup(cacheKey);
+					if (cache == null) {
+						cache = cacheCreator.create();
+						cacheStorager.caching(cacheKey, cache);
+					}
+				} finally {
+					lock.unlock();
+				}
+			}
+		} catch (InterruptedException e) {
+			throw new WeixinException("get cache error on lock", e);
 		}
 		return cache;
 	}