如何在不参考规范的情况下在命令行上获取 -xx 支持的所有参数的列表？
java -X
-Xmixed mixed mode execution (default)
-Xint interpreted mode execution only
-Xbootclasspath:<directories and zip/jar files separated by :>
set search path for bootstrap classes and resources
-Xbootclasspath/a:<directories and zip/jar files separated by :>
append to end of bootstrap class path
-Xbootclasspath/p:<directories and zip/jar files separated by :>
prepend in front of bootstrap class path
-Xdiag show additional diagnostic messages
-Xnoclassgc disable class garbage collection
-Xincgc enable incremental garbage collection
-Xloggc:<file> log GC status to a file …