line.separator

在进行文件处理时，要经常对文件中的每一行进行处理，处理完一行将结果输出到BufferedWriter，此时还要输出一个换行符。

Linux下换行符号可以用"\n"来表示，但在Windows下是不可以的，Windows用的是"\r\n"。为了让自己写的程序具有比较好的一致性，java其实提供了统一的特殊符号。对于换行符号可以System.getProperty("line.separator")来获取。

public class JavaClassDirectory {

publicstatic void main(String[] args) {

System.out.println(System.getProperty("java.version"));

System.out.println(System.getProperty("java.vendor"));

System.out.println(System.getProperty("java.home"));

System.out.println(System.getProperty("line.separator"));

}

}

其他系统属性：

Key	Description of Associated Value
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