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1¡¢ÀûÓÃSystem.getProperty()º¯Êý»ñÈ¡µ±Ç°Â·¾¶£º
System.out.println(System.getProperty("user.dir"));//user.dirÖ¸¶¨Á˵±Ç°µÄ·¾¶
2¡¢Ê¹ÓÃFileÌṩµÄº¯Êý»ñÈ¡µ±Ç°Â·¾¶£º
File directory = new File("");//É趨Ϊµ±Ç°Îļþ¼Ð
try{
System.out.println(directory.getCanonicalPath());//»ñÈ¡±ê×¼µÄ·¾¶
System.out.println(directory.getAbsolutePath());//»ñÈ¡¾ø¶Ô·¾¶
}catch(Exceptin e){}
File.getCanonicalPath()ºÍFile.getAbsolutePath()´óÔ¼Ö»ÊǶÔÓÚnew File(".")ºÍnew File("..")Á½ÖÖ·¾¶ÓÐËùÇø±ð¡£
# ¶ÔÓÚgetCanonicalPath()º¯Êý£¬“."¾Í±íʾµ±Ç°µÄÎļþ¼Ð£¬¶ø”..“Ôò±íʾµ±Ç°Îļþ¼ÐµÄÉÏÒ»¼¶Îļþ¼Ð
# ¶ÔÓÚgetAbsolutePath()º¯Êý£¬Ôò²»¹Ü”.”¡¢“..”£¬·µ»Øµ±Ç°µÄ·¾¶¼ÓÉÏÄãÔÚnew File()ʱÉ趨µÄ·¾¶
# ÖÁÓÚgetPath()º¯Êý£¬µÃµ½µÄÖ»ÊÇÄãÔÚnew File()ʱÉ趨µÄ·¾¶
±ÈÈ統ǰµÄ·¾¶Îª C:\test £º
File directory = new File("abc");
directory.getCanonicalPath(); //µÃµ½µÄÊÇC:\test\abc
directory.getAbsolutePath(); //µÃµ½µÄÊÇC:\test\abc
direcotry.getPath(); //µÃµ½µÄÊÇabc
File directory = new File(".");
directory.getCanonicalPath(); //µÃµ½µÄÊÇC:\test
directory.getAbsolutePath(); //µÃµ½µÄÊÇC:\test\.
direcotry.getPath(); //µÃµ½µÄÊÇ.
File directory = new File("..");
directory.getCanonicalPath(); //µÃµ½µÄÊÇC:\
directory.getAbsolutePath(); //µÃµ½µÄÊÇC:\test\..
direcotry.getPath(); //µÃµ½µÄÊÇ..
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# java.version Java Runtime Environment version
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