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1 ¡¢ÀûÓà System.getProperty() º¯Êý»ñÈ¡µ±Ç°Â·¾¶£º
System.out.println(System.getProperty("user.dir"));//user.dir Ö¸¶¨Á˵±Ç°µÄ·¾¶
2 ¡¢Ê¹Óà File ÌṩµÄº¯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() ºÍ File.getAbsolutePath() ´óÔ¼Ö»ÊǶÔÓÚ new File(".") ºÍ new File("..") Á½ÖÖ·¾¶ÓÐËùÇø±ð¡£
# ¶ÔÓÚ getCanonicalPath() º¯Êý£¬“ ." ¾Í±íʾµ±Ç°µÄÎļþ¼Ð£¬¶ø” .. “Ôò±íʾµ±Ç°Îļþ¼ÐµÄÉÏÒ»¼¶Îļþ¼Ð
# ¶ÔÓÚ getAbsolutePath() º¯Êý£¬Ôò²»¹Ü” . ”¡¢“ .. ”£¬·µ»Øµ±Ç°µÄ·¾¶¼ÓÉÏÄãÔÚ new File() ʱÉ趨µÄ·¾¶
# ÖÁÓÚ getPath() º¯Êý£¬µÃµ½µÄÖ»ÊÇÄãÔÚ new File() ʱÉ趨µÄ·¾¶
±ÈÈ統ǰµÄ·¾¶Îª C:\test £º
File directory = new File("abc");
directory.getCanonicalPath(); // µÃµ½µÄÊÇ C:\test\abc
directory.getAbsolutePath(); // µÃµ½µÄÊÇ C:\test\abc
direcotry.getPath(); // µÃµ½µÄÊÇ abc
File directory = new File(".");
directory.getCanonicalPath(); // µÃµ½µÄÊÇ C:\test
directory.getAbsolutePath(); // µÃµ½µÄÊÇ C:\test\.
direcotry.getPath(); // µÃµ½µÄÊÇ .
File directory = new File("..");
directory.getCanonicalPath(); // µÃµ½µÄÊÇ C:\
directory.getAbsolutePath(); // µÃµ½µÄÊÇ C:\test\..
direcotry.getPath(); // µÃµ½µÄÊÇ ..
¹ØÓÚSystem.getProperty·½·¨µÄ²ÎÊý¼û
System.getProperty
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Á˽âȱʡLocaleÊÇÓɲÙ×÷ϵͳ¾ö¶¨µÄ£¬LocaleÊÇÓÉÓïÑԺ͹ú¼Ò´úÂë×é³É
¹ú¼Ê»¯×ÊÔ´ÎļþÓÉbaseName+locale×é³É£¬È磺MessageBundle_en_US.properties£¨baseNameÊÇÈÎÒâºÏ·¨µÄÎļþÃû£©
native2asciiÃüÁîµÄλÖúÍÓ÷¨
λÖãºJAVA_HOME/bin
ʹÓÃnative2ascii.exe o.properties MessagesBundle_zh_CN.properties ÃüÁî¶ÔÕû¸öÎļþ ......
System.out.println(2|0); //0010 0000 =>0010 = 2
System.out.println(2|1); //0010 0001 =>0011 = 3
System.out.println(3|2); //0011 0010 =>0011 = 3
System.out.println(3&2); //0011 0010 =>0010 = 2
/*
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00011|0010 ´ÓÓÒµ½×ó±È½Ï0|1 = 1, 1|0 = ......
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1.1 ¼¯ºÏ¿ò¼Ü¸ÅÊö... 2
1.1.1 ÈÝÆ÷¼ò½é... 2
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1.2 Collection. 5
1.2.1  ......
תÌù£ºhttp://lvp.javaeye.com/blog/356650
1.ÈçºÎÀí½âException,ErrorºÍThrowable
ThrowableÊÇExceptionºÍErrorµÄ¸¸Àà.
Error±íʾ´íÎó£¬Ò»°ãÊÇϵͳ¼¶µÄ´íÎó£¡
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תÌù£ºhttp://java.ccidnet.com/art/3539/20070924/1222147_1.html
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