更好的控制Java程序的行爲，使用Java虛擬機參數

Java程序執行在Java虛擬機至上，我們可以通過參數配置Java虛擬機的行爲。

• Options that begin with -X are non-standard (not guaranteed to be supported on all VM implementations), and are subject to change without notice in subsequent releases of the JDK.
• Options that are specified with -XX are not stable and are subject to change without notice.

詳情:

http://www.oracle.com/technetwork/java/javase/tech/vmoptions-jsp-140102.html