JAVA»ñȡϵͳÐÅÏ¢
Properties props=System.getProperties(); //ϵͳÊôÐÔ
System.out.println("JavaµÄÔËÐл·¾³°æ±¾£º"+props.getProperty("java.version"));
System.out.println("JavaµÄÔËÐл·¾³¹©Ó¦ÉÌ£º"+props.getProperty("java.vendor"));
System.out.println("Java¹©Ó¦É̵ÄURL£º"+props.getProperty("java.vendor.url"));
System.out.println("JavaµÄ°²×°Â·¾¶£º"+props.getProperty("java.home"));
System.out.println("JavaµÄÐéÄâ»ú¹æ·¶°æ±¾£º"+props.getProperty("java.vm.specification.version"));
System.out.println("JavaµÄÐéÄâ»ú¹æ·¶¹©Ó¦ÉÌ£º"+props.getProperty("java.vm.specification.vendor"));
System.out.println("JavaµÄÐéÄâ»ú¹æ·¶Ãû³Æ£º"+props.getProperty("java.vm.specification.name"));
System.out.println("JavaµÄÐéÄâ»úʵÏÖ°æ±¾£º"+props.getProperty("java.vm.version"));
System.out.println("JavaµÄÐéÄâ»úʵÏÖ¹©Ó¦ÉÌ£º"+props.getProperty("java.vm.vendor"));
System.out.println("JavaµÄÐéÄâ»úʵÏÖÃû³Æ£º"+props.getProperty("java.vm.name"));
System.out.println("JavaÔËÐÐʱ»·¾³¹æ·¶°æ±¾£º"+props.getProperty("java.specification.version"));
System.out.println("JavaÔËÐÐʱ»·¾³¹æ·¶¹©Ó¦ÉÌ£º"+props.getProperty("java.specification.vender"));
System.out.println("JavaÔËÐÐʱ»·¾³¹æ·¶Ãû³Æ£º"+props.getProperty("java.specification.name"));
System.out.println("JavaµÄÀà¸ñʽ°æ±¾ºÅ£º"+props.getProperty("java.class.version"));
System.out.println("JavaµÄÀà·¾¶£º"+props.getProperty("java.class.path"));
System.out.println("¼ÓÔØ¿âʱËÑË÷µÄ·¾¶ÁÐ±í£º"+props.getProperty("java.library.path"));
System.out.println("ĬÈϵÄÁÙʱÎļþ·¾¶£º"+props.getProperty("java.io.tmpdir"));
System.out.println("Ò»¸ö»ò¶à¸öÀ©Õ¹Ä¿Â¼µÄ·¾¶£º"+props.getProperty("java.ext.dirs"));
System.out.println("²Ù×÷ϵͳµÄÃû³Æ£º"+props.getProperty("os.name"));
System.out.println("²Ù×÷ϵͳµÄ¹¹¼Ü£º"+props.getProperty("os.arch"));
System.out.println("²Ù×÷ϵͳµÄ°æ±¾£º"+props.getProperty("os.version"));
System.out.println("Îļþ·Ö¸ô·û£º"+props.getProperty("file.separator")); //ÔÚ unix ϵͳÖÐÊÇ£¢£¯£¢
System.out.println("·¾¶·Ö¸ô·û£º"+props.getProperty("pat
Ïà¹ØÎĵµ£º
1. Òò×Ó
ÉϴνéÉÜÁË¡¶JAVAʵÏÖAES¼ÓÃÜ¡·£¬ÖмäÌáµ½½üЩÄêDESʹÓÃÔ½À´Ô½ÉÙ£¬ÔÒò¾ÍÔÚÓÚÆäʹÓÃ56λÃÜÔ¿£¬±È½ÏÈÝÒ×±»ÆÆ½â£¬½üЩÄêÀ´Öð½¥±»AESÌæ´ú£¬AESÒѾ±ä³ÉĿǰ¶Ô³Æ¼ÓÃÜÖÐ×îÁ÷ÐÐËã·¨Ö®Ò»£»AES¿ÉÒÔʹÓÃ128¡¢192¡¢ºÍ256λÃÜÔ¿£¬²¢ÇÒÓÃ128λ·Ö×é¼ÓÃܺͽâÃÜÊý¾Ý¡£±¾Îľͼòµ¥½éÉÜÈç ......
1. StrutsÌåϵ½á¹¹ÊµÏÖÁËMVCÉè¼ÆÄ£Ê½µÄ¸ÅÄÄÇôËü½«ÒÔÏÂÑ¡ÏîÖиø³öµÄʲô·Ö±ðÓ³ÉäΪwebÓ¦ÓÃÖеÄ×é¼þ£¿£¨ £©
A View
B Model
C ActionServlet
D Action
E ActionMapping
F Controller
²Î¿¼´ð°¸£ºABF
2. ÔÚStrutsÌåϵ½á¹¹ÖУ¬ÒÔÏÂÄĸöÓÉ´ú±íϵͳ״̬ºÍÉÌÒµÂß¼µÄActionÀ´¹¹½¨ ......
Java³ÉÔ±µÄĬÈÏ·ÃÎÊ¿ØÖÆ
ÎÒ¶¥¶ÔÓÚÒ»¸öClassµÄ³ÉÔ±±äÁ¿»ò³ÉÔ±º¯Êý£¬Èç¹û²»ÓÃpublic, protected, privateÖеÄÈκÎÒ»¸öÐÞÊΣ¬ÄÇô¸Ã³ÉÔ±»ñµÃ“ĬÈÏ·ÃÎÊ¿ØÖÆ”¼¶±ð£¬¼´package access £¨°ü·ÃÎÊ£©¡£
ÊôÓÚpackage accessµÄ³ÉÔ±¿ÉÒÔ±»Í¬Ò»¸ö°üÖÐµÄÆäËûÀà·ÃÎÊ£¬µ«²»Äܱ»ÆäËû°üµÄÀà·ÃÎÊ¡£
° ......
JAVAÖеĴ«µÝ¶¼ÊÇÖµ´«µÝÂð£¿ÓÐûÓÐÒýÓô«µÝÄØ£¿
ÔڻشðÕâÁ½¸öÎÊÌâǰ£¬ÈÃÎÒÃÇÊ×ÏÈÀ´¿´Ò»¶Î´úÂ룺
Java´úÂë
public class ParamTest {
// ³õʼֵΪ0
protected int num = 0;
// Ϊ·½·¨²ÎÊýÖØÐ¸³Öµ
public void change(int i) {
i = 5;
}
// Ϊ·½·¨²ÎÊýÖØÐ¸³Öµ
public void change(ParamTest t) {
P ......