我们只需要实现这个方法就可以了。
这篇文章写的很详细，一看就明白了。
http://linhongyu.blog.51cto.com/6373370/1615895
2.数据库实现读写分离
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数据库读写分离
标签：引用 个数 方法 call 操作 work .com action ring
数据库读写分离
* Determine the current lookup key. This will typically be
* implemented to check a thread-bound transaction context.
* <p>Allows for arbitrary keys. The returned key needs
* to match the stored lookup key type, as resolved by the
* {@link #resolveSpecifiedLookupKey} method.
*/
protected abstract Object determineCurrentLookupKey();