Xmemcached与Spring 3.0的集成

昨天收到一个xmc的issue报告，大概的意思是将
Xmemcached
与spring 2.5集成没有任何问题，但是将spring升级到3.0就会抛出一个异常，并且spring容器无法正常启动，异常信息类似“
Couldn't find a destroy method named 'shutdown' on bean XMemcachedClientFactoryBean”。更详细的情况可以看这里，这是这位朋友分析的结果，简单来说就是spring 3.0对于查找destroy method为空的情况处理不同了，过去是打个日志，现在是抛出一个异常。
问题说完，这里主要是介绍下这个问题的解决方式，事实上Xmemcached有一个没有被文档化的Spring配置方式，没有写入文档的主要考虑是以为wiki介绍的第一种方式已经足够，而builder的方式相对繁琐一些。通过XmemcachedClientBuilder的这个factory bean的factory-method，也就是build方法来构建MemcachedClient，这就可以绕开spring 3.0的这个问题。一个示范配置如下：

<
bean
name
="memcachedClientBuilder"
class
="net.rubyeye.xmemcached.XMemcachedClientBuilder"
>

<
constructor-arg
>

<
list
>

<
bean
class
="java.net.InetSocketAddress"
>

<
constructor-arg
>

<
value
>localhost
</
value
>

</
constructor-arg
>

<
constructor-arg
>

<
value
>12000
</
value
>

</
constructor-arg
>

</
bean
>

</
list
>

</
constructor-arg
>

</
bean
>

<
bean
name
="memcachedClient"
factory-bean
="memcachedClientBuilder"

factory-method
="build"
destroy-method
="shutdown"

/>

memcachedClientBuilder作为一个factory-bean，接受一个InetSocketAddress列表作为构造函数传入，最后MemcachedClient就可以通过factory-method——也就是build方法创建了。

多个节点情况下，可能你想设置权重，那么传入memcachedClientBuilder的第二个构造函数
参数权重数组
即可：

<
bean
name
="memcachedClientBuilder"
class
="net.rubyeye.xmemcached.XMemcachedClientBuilder"
>

<
constructor-arg
>

<
list
>

<
bean
class
="java.net.InetSocketAddress"
>

<
constructor-arg
>

<
value
>localhost
</
value
>

</
constructor-arg
>

<
constructor-arg
>

<
value
>12000
</
value
>

</
constructor-arg
>

</
bean
>

<
bean
class
="java.net.InetSocketAddress"
>

<
constructor-arg
>

<
value
>localhost
</
value
>

</
constructor-arg
>

<
constructor-arg
>

<
value
>12001
</
value
>

</
constructor-arg
>

</
bean
>

</
list
>

</
constructor-arg
>

<
constructor-arg
>

<
list
>

<
value
>1
</
value
>

<
value
>2
</
value
>

</
list
>

</
constructor-arg
>

</
bean
>

<
bean
name
="memcachedClient"
factory-bean
="memcachedClientBuilder"

factory-method
="build"
destroy-method
="shutdown"

/>

上面的例子将localhost:12000的权重设置为1，而localhost:12001的权重设置为2。除了这些配置外，XmemcachedClientBuilder还有其他选项，如配置一致性哈希算法、连接池等，完整的配置例子如下：

<
bean
name
="memcachedClientBuilder"
class
="net.rubyeye.xmemcached.XMemcachedClientBuilder"
>

<!--
XMemcachedClientBuilder have two arguments.First is server list,and second is weights array.
-->

<
constructor-arg
>

<
list
>

<
bean
class
="java.net.InetSocketAddress"
>

<
constructor-arg
>

<
value
>localhost
</
value
>

</
constructor-arg
>

<
constructor-arg
>

<
value
>12000
</
value
>

</
constructor-arg
>

</
bean
>

<
bean
class
="java.net.InetSocketAddress"
>

<
constructor-arg
>

<
value
>localhost
</
value
>

</
constructor-arg
>

<
constructor-arg
>

<
value
>12001
</
value
>

</
constructor-arg
>

</
bean
>

</
list
>

</
constructor-arg
>

<
constructor-arg
>

<
list
>

<
value
>1
</
value
>

<
value
>2
</
value
>

</
list
>

</
constructor-arg
>

<
property
name
="connectionPoolSize"
value
="2"
></
property
>

<
property
name
="commandFactory"
>

<
bean
class
="net.rubyeye.xmemcached.command.TextCommandFactory"
></
bean
>

</
property
>

<
property
name
="sessionLocator"
>

<
bean
class
="net.rubyeye.xmemcached.impl.KetamaMemcachedSessionLocator"
></
bean
>

</
property
>

<
property
name
="transcoder"
>

<
bean
class
="net.rubyeye.xmemcached.transcoders.SerializingTranscoder"

/>

</
property
>

</
bean
>

<!--
Use factory bean to build memcached client
-->

<
bean
name
="memcachedClient"
factory-bean
="memcachedClientBuilder"

factory-method
="build"
destroy-method
="shutdown"
/>