java 获取当前路径

公司项目中，获取当前路径的方法是这样的：
C
view plaincopy to clipboardprint?//当前的类名就是：GetFilePath
public static String getFilePath(String fileName)
{
String path = GetFilePath.class.getResource("").toString();

if (path != null)
{
path = path.substring(5, path.indexOf("WEB-INF") + 8);//如果是windwos将5变成6
//System.out.println("current path :" + path);
}
return (path + fileName);
}

view plaincopy to clipboardprint?System.out.println(System.getProperty("user.dir"));//user.dir指定了当前的路径
System.out.println(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：
view plaincopy to clipboardprint?File directory = new File("");//设定为当前文件夹
try{
System.out.println(directory.getCanonicalPath());//获取标准的路径
System.out.println(directory.getAbsolutePath());//获取绝对路径
}catch(Exceptin e){}

view plaincopy to clipboardprint?request.getContextPath()
request.getSession().getServletContext().getRealPath()
request.getContextPath()request.getSession().getServletContext().getRealPath()

servlet中:
view plaincopy to clipboardprint?this.getServletContext().getRealPath("/");
this.getServlet().getServletContext().getRealPath("/");
this.getServletContext().getRealPath("/"); this.getServlet().getServletContext().getRealPath("/");

其他说明：
File.getCanonicalPath()和File.getAbsolutePath()大约只是对于new File(".")和new File("..")两种路径有所区别。
# 对于getCanonicalPath()函数，“."就表示当前的文件夹，而”..“则表示当前文件夹的上一级文件夹
# 对于getAbsolutePath()函数，则不管”.”、“..”，返回当前的路径加上你在new File()时设定的路径
# 至于getPath()函数，得到的只是你在new File()时设定的路径
比如当前的路径为 C:/test ：
File directory = new File("abc");
directory.getCanonicalPath(); //得到的是C:/test/abc
directory.getAbsolutePath(); //得到的是C:/test/abc
direcotry.getPath(); //得到的是abc
File directory = new File(".");
directory.getCanonicalPath(); //得到的是C:/test
directory.getAbsolutePath(); //得到的是C:/test/.
direcotry.getPath(); //得到的是.
File directory = new File("..");
directory.getCanonicalPath(); //得到的是C:/
directory.getAbsolutePath(); //得到的是C:/test/..
direcotry.getPath(); //得到的是..

另外：System.getProperty()中的字符串参数如下：
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