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setenv PATH /bin:/p/2002-11-14/6302.html
Windowsƽ̨: set JAVA_HOME=Java2µÄ°²×°Â·¾¶
set PATH=;%PATH%
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Èç¹ûÔÚNetscape»òIEä¯ÀÀÆ÷ÖÐÔËÐÐJava appletʱ³öÏÖÁË´íÎó,ÈçºÎÈ·¶¨´íÎó·¶Î§?
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µ±java appletÔÚä¯ÀÀÆ÷ÖÐÔËÐÐʱ,ʹÓõÄÊÇä¯ÀÀÆ÷±¾ÉíµÄȱʡJVM.¶ø²»Í¬ä¯ÀÀÆ÷¶ÔJDKµÄÖ§³Ö³Ì¶ÈÒ²²»¾¡Ïàͬ. Òò´Ë,ÔÚNetscape»òIEä¯ÀÀÆ÷ÖÐÔËÐÐJava applet³öÏÖÁË´íÎó,½¨ÒéʹÓÃJDKÌṩµÄ¹¤¾ßappletviewer»òSun¹«Ë¾µÄHotjavaä¯ÀÀÆ÷À´²âÊÔ¸Ãapplet,ÒÔÈ·¶¨´íÎóµÄ²úÉúÊÇÓëä¯ÀÀÆ÷Ïà¹Ø.
Èç¹ûappletÔÚappletviewer»òHotjavaÖÐÔËÐÐÒ»ÇÐÕý³£,Ôò´íÎóµÄ²úÉúÊÇÓÉÓÚä¯ÀÀ Æ÷²»ÍêÈ«¼æÈÝJDK¶øÒýÆðµÄ. ´Ëʱ,½â¾ö·½·¨¿ÉÒÔÊÇʹÓÃHotjavaä¯ÀÀÆ÷»òÕß°²×° Sun¹«Ë¾µÄJava Plugin.
Èç¹ûappletÔÚHotjavaä¯ÀÀÆ÷»òappletviewerÖÐÔËÐм´·¢Éú´íÎó,ÔòÓ¦µ±¸ù¾Ý´íÎó Ìáʾ¼ì²éapplet³ÌÐò.
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µ±ÓÃJDBCÏòÊý¾Ý¿âÖвåÈëÊý¾Ý»ò´ÓÊý¾Ý¿âÖÐÌáÈ¡Êý¾Ýʱ,ΪºÎÓÐʱÖÐÎÄ×Ö·û»áÏÔʾΪÂÒÂë?
´ð:
Õâ¸öÎÊÌâµÄʵÏÖͨ³£Óë¸÷¸öJDBC driverµÄʵÏÖÓйØ. Ŀǰ´ó¶àÊýJDBC driver²ÉÓñ¾µØ±àÂë¸ñʽÀ´´«ÊäÖÐÎÄ×Ö·û,ÀýÈçÖÐÎÄ×Ö·û"0x4175"»á±»×ª³É"0x41"ºÍ"0x75"½øÐд«Êä. Òò´ËÎÒÃÇÐèÒª¶ÔJDBC driver·µ»ØµÄ×Ö·ûÒÔ¼°Òª·¢¸øJDBC driverµÄ×Ö·û½øÐÐת»».
µ±ÓÃJDBC driverÏòÊý¾Ý¿âÖвåÈëÊý¾Ýʱ,ÐèÒªÏȽ«Unicodeת³Énative code; µ± JDBC driver´ÓÊý¾Ý¿âÖвéѯÊý¾Ýʱ,ÔòÐèÒª½«native codeת»»³ÉUnicode. ÏÂÃæ¸ø³öÁËÕâÁ½ÖÖת»»µÄʵÏÖ:
String native2Unicode(String s) {
if (s == null || s.length() == 0) {
return null;
}
byte[] buffer = new byte[s.length()];
for (int i = 0; i s.length(); i++) { if (s.charAt(i)>= 0x100) {
c = s.charAt(i);
byte []buf = (""+c).getBytes();
buffer[j++] = (char)buf[0];
buffer[j++] = (char)buf[1];
}
else {
buffer[j++] = s.charAt(i);
}
}
return new String(buffer, 0, j);
}
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Effective Java ѧϰ±Ê¼Ç(4)

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