System.getProperty() 参数大全
java.version Java Runtime Environment version
java.vendor Java Runtime Environment vendor
java.vendor.url Java vendor URL
java.home Java installation directory
java.vm.specification.version Java Virtual Machine specification version
java.vm.specification.vendor Java Virtual Machine specification vendor
java.vm.specification.name Java Virtual Machine specification name
java.vm.version Java Virtual Machine implementation version
java.vm.vendor Java Virtual Machine implementation vendor
java.vm.name Java Virtual Machine implementation name
java.specification.version Java Runtime Environment specification version
java.specification.vendor Java Runtime Environment specification vendor
java.specification.name Java Runtime Environment specification name
java.class.version Java class format version number
java.class.path Java class path
java.library.path List of paths to search when loading libraries
java.io.tmpdir Default temp file path
java.compiler Name of JIT compiler to use
java.ext.dirs Path of extension directory or directories
os.name Operating system name
os.arch Operating system architecture
os.version Operating system version
file.separator File separator ("/" on UNIX)
path.separator Path separator (":" on UNIX)
line.separator Line separator ("\n" on UNIX)
user.name User's account name
user.home User's home directory
user.dir User's current working directory
使用System.getProperty("user.dir").这个是我在程序当中用的最多的，也是比较容易混淆的地方。解释为:用户当前的工作目录。所谓的当前的工作目录是指 ： 程序在那个地方运行这个目录就在那里。举个列子 ------
C:\Documents and Settings\sundl>D:
D:\>cd workspaces\Html
D:\workspaces\Html>java Test
这时，user.dir就成了D:\workspaces\Html
简单的一点说就是 ：
在哪里java <yourClass>
哪里就是你的working directory.
