Ò׽ؽØÍ¼Èí¼þ¡¢µ¥Îļþ¡¢Ãâ°²×°¡¢´¿ÂÌÉ«¡¢½ö160KB

ÄãÄÜͨ¹ýÏÂÃæµÄ3µÀjavaÃæÊÔÌâÂð?

1.java static inner class ºÍ non-static inner classµÄÇø±ð?
2.Çëд³öÒ»¸ösingletonģʽµÄclass.
ÄãÈç¹ûд³öÏÂÃæµÄ2ÖÖÑùʽ,ÎÒ»áÎÊÄã:ÇëÎÊÄãÈçºÎÔÚͬһ¸öjvmÖв¢ÇÒÔÚͬһ¸öclassLoaderÖеõ½ËüµÄ¶à¸öʵÀý?(Çë²»ÒªÆæ¹Ö)
ÑùÁÐ1:
public class Singleton {  
 private final static Singleton instance=new Singleton();
 private Singleton(){} 
 public static Singleton newInstance(){  
  return instance;  
 } 
}
ÑùÁÐ2:
public class Singleton { 
 private static volatile int instanceCounter=0; 
 private Singleton(){
  if(instanceCounter>0)
   throw new RuntimeException("can't create multi instances!");
  instanceCounter++;
 }
 
 private final static Singleton instance=new Singleton();
 public static Singleton newInstance(){  
  return instance;  
 }
}
3.java µÄexception ·Öchecked,unchecked.ÏñRuntimeException,Error¶¼²»ÓÃÏÔʽtry-catch,Ö±½Ó¿ÉÒÔthrow,
µ«ÊÇÒ»°ãµÄexceptionÊDZØÐëcatchµÄ:
throw new Exception("..."),Èç¹ûÕâ¾ä²»ÔÚtry-catchÌåÄÚ,»òÕß·½·¨µÄÉùÃ÷ûÓÐthrows,ÄÇô±àÒëÊÇͨ²»¹ýµÄ.
ok,Çë¿´ÈçϵĴúÂë:
public class TestClass { 
 
 public void  testMethod()/*ÕâÀïûÓÐthrows Ŷ!*/{  
          ......
           throw new Exception("force throw the exception...");
          ......
 }
}
ºÜÃ÷ÏÔÉÏÃæµÄ·½·¨Èç¹ûÕâÑùµÄ»°ÊÇͨ²»¹ý±àÒëµÄ,µ«ÊÇÈç¹û·ÇµÃÒªÄãÔÚtestMethodÌåÖÐÔÚÔËÐÐʱthrowÒ»¸öºÜÒ»°ãµÄException,ÇëÎÊÄãÓа취Âð? 
Õâ3µÀÌâ¿É²»ÊÇsun³öµÄ¿¼ÌâŶ!²»ÐÅÄãËÑËÑ......


Ïà¹ØÎĵµ£º

javaÖÐʹÓÃsqliteÊý¾Ý¿â

sqliteÊý¾Ý¿âµÚÈý·½javaÀ©Õ¹°üÏÂÔØµØÖ·£ºhttp://www.zentus.com/sqlitejdbc/
ÓÐ2¸ö°ü£¬Ò»¸öÊÇnested£¨Ç¶ÈëʽµÄ£©£¬Ò»¸öÊÇnative(±¾µØµÄ)¡£
Çø±ðÔÚÓÚ:nested ²»ÐèÒª¶îÍâµÄdllÎļþ£¬µ«ÊÇËÙ¶ÈÂý¡£nativeÐèÒªÒ»¸ö¶îÍâµÄdllÎļþ£¬ËٶȺܿ졣
 1.ʹÓÃnested°ü£ºsqlitejdbc-v037-nested.jar
java´úÂ룺
java ´úÂë
packa ......

javaÖÐʹÓÃibatisÀ´µ÷Óô洢¹ý³Ì(ÉÏ)

ÎÒÃÇÔÚ½øÐÐpl/sql±à³Ìʱ´ò½»µÀ×î¶àµÄ¾ÍÊÇ´æ´¢¹ý³ÌÁË¡£´æ´¢¹ý³ÌµÄ½á¹¹ÊǷdz£µÄ¼òµ¥µÄ£¬ÎÒÃÇÔÚÕâÀï³ýÁËѧϰ´æ´¢¹ý³ÌµÄ»ù±¾½á¹¹Í⣬»¹»áѧϰ±àд´æ´¢¹ý³ÌʱÏà¹ØµÄһЩʵÓõÄ֪ʶ¡£È磺ÓαêµÄ´¦Àí£¬Òì³£µÄ´¦Àí£¬¼¯ºÏµÄÑ¡ÔñµÈµÈ
1.´æ´¢¹ý³Ì½á¹¹
1.1 µÚÒ»¸ö´æ´¢¹ý³Ì
create or replace procedure proc1(   
  ......

ÔÚJava³ÌÐòÖнػñ¿ØÖÆÌ¨Êä³ö

     ±¾ÎĵÄÄ¿±êÊÇÉè¼ÆÒ»¸ö»ùÓÚSwingµÄJTextAreaÏÔʾ¿ØÖÆÌ¨Êä³ö¡£´ËÆÚ¼ä£¬ÎÒÃÇ»¹½«ÌÖÂÛһЩºÍJava¹ÜµÀÁ÷£¨PipedInputStreamºÍPipedOutputStream£©ÓйصÄ×¢ÒâÊÂÏî¡£×îºó»¹Òª´´½¨Ò»¸öÄܹ»²¶»ñºÍÏÔʾÆäËû³ÌÐò£¨¿ÉÒÔÊÇ·ÇJavaµÄ³ÌÐò£©¿ØÖÆÌ¨Êä³öµÄ¼òµ¥³ÌÐò¡£
Ò»¡¢Java¹ÜµÀÁ÷
     ÒªÔÚÎı¾ ......

IOÓëÎļþ¶Áд JavaµÄIOÁ÷¼Ü¹¹

¡¾Ò»¡¿»ùÓÚ×Ö½ÚµÄÊäÈëÁ÷
ÖµµÃ×¢ÒâµÄµØ·½ÓУº
¢ÙLevel 2µÄÊäÈëÁ÷£¬´ó¶àÊý¶¼»áÖ¸Ã÷Êý¾ÝÔ´µÄÐÎʽ£ºÀýÈçByteArray£¬File£¬Piped
¢ÚLevel 3µÄÊäÈëÁ÷£¬Ôò²»»á³öÏÖ¾ßÌåµÄÊý¾ÝÔ´Ãû×Ö£¬¶øÊÇÒÔ¹¦ÄÜÈ¡´ú£ºÀýÈçBuffered£¬LineNumber
ËùÒÔ˵Level 3µÄÊäÈëÁ÷ÊǶÔLevel 2ÊäÈëÁ÷µÄ“·â×°ºÍ¹ýÂË”¡£Êµ¼ÊÉÏLevel 2µÄÊäÈëÁ÷£¬¶ ......

dzÎöJavaµÄ¡°¿Ë¡¡±·½·¨ תÌù

ZT:http://javahy.javaeye.com/blog/384871
¡¡¡¡JavaÓïÑÔµÄÒ»¸öÓŵã¾ÍÊÇÈ¡ÏûÁËÖ¸ÕëµÄ¸ÅÄµ«Ò²µ¼ÖÂÁËÐí¶à³ÌÐòÔ±ÔÚ±à³ÌÖг£³£ºöÂÔÁ˶ÔÏóÓëÒýÓõÄÇø±ð£¬±¾ÎÄ»áÊÔͼ³ÎÇåÕâÒ»¸ÅÄî¡£²¢ÇÒÓÉÓÚJava²»ÄÜͨ¹ý¼òµ¥µÄ¸³ÖµÀ´½â¾ö¶ÔÏó¸´ÖƵÄÎÊÌ⣬ÔÚ¿ª·¢¹ý³ÌÖУ¬Ò²³£³£ÒªÒªÓ¦ÓÃclone£¨£©·½·¨À´¸´ÖƶÔÏó¡£±¾ÎÄ»áÈÃÄãÁ˽âʲôÊÇÓ°×Óclone ......
© 2009 ej38.com All Rights Reserved. ¹ØÓÚE½¡ÍøÁªÏµÎÒÃÇ | Õ¾µãµØÍ¼ | ¸ÓICP±¸09004571ºÅ