[ 源代码： unsafe-fences ]
软件包：libunsafe-fences-java（1.0-1.1）
wrapper library around the Java 8 fences API
unsafe-fences is a very simple Java library that just provides a shim around the Java 8 Unsafe methods used for memory fencing.
In Java 8, three memory-ordering intrinsics were added to the sun.misc.Unsafe class: fullFence, storeFence, and loadFence.
The main goal of unsafe-fences is to allow code in Java 6 and 7 to compile those calls with a provided boolean guard.
This is especially useful for projects like JRuby that support several JDK versions but it can be reused by other Java projects as well.