java获取当前路径

1 利用System.getProperty()函数获取当前路径

System.getProperty("user.dir");//user.dir指定了当前的路径

2 使用File提供的函数获取当前路径

假设当前目录为C:/test
1、 new File("")

    File file = new File(""); // 空字符串表示为设定当前文件
    System.out.println(file.getCanonicalPath()); // 获取标准的路径
    System.out.println(file.getAbsolutePath());  // 获取绝对路径
    System.out.println(file.getPath());  //

2、 new File(".")

    File file = new File("."); // 空字符串表示为设定当前文件
    System.out.println(file.getCanonicalPath()); // 获取标准的路径
    System.out.println(file.getAbsolutePath());  // 获取的路径比上面多一个\.
    System.out.println(file.getPath());  // .

3、 new File("…")

    File file = new File("."); // 空字符串表示为设定当前文件
    System.out.println(file.getCanonicalPath()); // 获取标准的路径
    System.out.println(file.getAbsolutePath());  // 获取的路径比上面多一个\test\.
    System.out.println(file.getPath());  // ..

3 System.getProperty()中的字符串参数如下

参数	说明
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