Java

1. ???? Java????? ?4? Java???????

2. ???? ????????????,?????????????Java????????????,???????????????????? ????????,??Java?????????;?????????????????;???????????????????

3. ???? Java??????? Java??????? Java??????? Java??????? ?????? ????

4. 4.1 Java??????? Java??????????????Java?????????????????,?????????????? Java??????:?????????????????

5. 4.1.1?????4-1? ?????????Java????? import java.lang // ???????????????????????? // ????????????????(???????) import java.io.*; // ??????????????????? public class SaleCount extends Object //?????????SaleCount? { public static void main(String[] args) { //Java?????main()???????? int totalCount; //???? int Count; //???? InputStreamReader stdin=new InputStreamReader(System.in); //???? BufferedReader bufin=new BufferedReader(stdin); //???? totalCount=0;

6. ?????????Java????? try { do //????: { System.out.println("???????????:"+totalCount+"?"); System.out.print("???????(????????????)"); Count=Integer.parseInt(bufin.readLine()); if(Count<0) break; else totalCount=totalCount+Count; }while(true); stdin.close(); bufin.close(); } catch (IOException E) { System.out.println("??I/O??"); } } } //??????,????????

7. 4.1.2 ????????? ???4-1:???????

10. 4.1.3 ???? ???????????: ?????????? ??: ???????: ???????????????????? ???????: ?????????????????????

11. ???? ???????????????????????,??????????(?????)???,????????????? ????: ???????????????????,??????????????? ???: ???static ??????????????????????????,???????????????????,??????????????,??????????? ????

12. ??????????????: public, friendly, protected, private, final, static? (1)public,?????????????????; (2)friendly,????????????????; (3)protected,????????????????? (4)private,?????????????,??????????????,???????????? ????????????????????? (5)final,?????????????????????????????????????,?????????????,????? ???????????????????? (6)static,????????????????????,?????“????”???static???

13. ???4-3:

14. ????

15. ???4-4

16. ???(???????) ?static??????????? (1)main???????,??Java??????,?????????????,??Java????????? (2)static?????????,??????????????????????; (3)??static???,???????????,???????????; (4)static??????static????,?????static????; (5)static??????static??,?????static??; (6)static???????,????,????????????????????

17. ???4-5

18. ???????? ??????Java???????,??????????????? ?Java?,??????????????,?????????????: [???] ????? ???(?????)[throw???] { ???? ?????? }

19. 1 ???????? final??????????????,??????????????? native???????????Java???????? abstract?????????????,????????,????????????????? Synchronized???????????;????????????????????,??????????,???????????,???????,?????????

20. 2 ??????????????? ?????:???????????????????? ????:???????????????????????????????????;???????????,??????????????????????????????????,????: (??????1 ?????1, ??????2 ?????2,……) throw???:????????????????????????????????????7???????

21. 4.1.4 ???? ?????????????,????????????????????????????,?????????????????????????? ????????,??????????????????,????????????????????????????,???????????;??????????(template)?

22. ???? ?——class ????????????,????????????????????(????)??????????????????????????

23. ????? ??——object

24. ????? ??——object

25. ???4-6 ??????:?????1??????Goods?????Show_Goods,???????? public class Show_Goods extends Goods { public static void main(String args[]) { Goods G1; // ???? G1 = new Goods( ) ; // ????,????????? G1.name = “electrical_equipment ”; // ?????,????????? G1.ShowGoods( ); } // ????????,?????? } ?????????:????,??????????

26. ?????1 ??????????? ??:?? ???; ??:Textfield input; ???????? ??:new ????(???); ??:new Textfield(10); ?new????????????? ??:?????=new ????(???) ??:input=new Textfield(10); ????????:?? ??? = new ????( );????????????????:?? ??? = new ????( );????????

27. ?????2 ?????? ?????3?????: ???????????? <??><???>=new <??>([????]) ??: (1)????: <??><???> ?:MyBox b1; (2)??????????? <???>=new <??>( [????] ) ?:MyBox b2=new MyBox(20,20,100,100)

28. ?????? ????????????????????????? ??????????????????? (1)???????(0,??,?,?); (2)????????????

29. ???????? MyBox( ) { x=0; y=0; width=0; height=0; } (??????)

30. ?????1 ??“.”?????????? ???.?????=??; ?:???.???=??; ??:Your_Clouth.color= “white”; //????????????? Your_Clouth.name= “ ”; //????????? ?????????????????????? ??:???????????setEmpNum(Num); ??????,<??.setEmpNum(1001); > ?????????<??.??Num>????1001?

31. ?????2 ?A?????????B??????,?????? ??:?A???=B???????: ?? A=new ??(); ?? B=new ??(); A=B; ???????,?????A???????? B??????,????A?????????? ??B???????,???????????? ?????

32. ?????1 ???? (1)<???>.<???> (2)<???>.<???>([????]) ??: Graphics g; g.drawRect (x, y, width, height);

33. ?????2 ???? ???????????????????,??????????????????????????,???????==??? if ??????? ???????????????????????????(???????????????,??????????????????)?????????????????,???????????equals()?????

34. ?????3 ???????? ????????????,??: int?????????0; boolean?????????false; ?????????null,??????null?????????????????null?,???????????????????,??????(Null Pointer Exception)?

35. ?????4 ???? ??????: ?? ???[ ]; ? ??[ ] ???; ?????????: ???=new ??[???????]; ????????????????: ??????????????????????????????????,????????????????????,??????????new??????????

36. ????? ?????????????? ??: Rectangle r=new Rectangle(5,5,5,5); …… r = null;

37. 4.1.5?????4-2?

42. ??????? ?????(?????)??? ??????: <???????> <?????> ??????: <?????> // ?????? this . <?????> ????(????)???: <??>.<????> ??????: <????> // ??????

43. ??????? ??????: <???>([???]) // ?????? ??????: <???>.<???>([???]) <??>.<???>([???]) ??????: (1)??????????????????? ?????????; (2)??????????????????? ??????; (3)??????????,???????? ?????

44. 4.1.6 ??????? ??????????????????,????????????????? * ???????????,????????? ??(instance); * ??????????(template)?

45. ??????? ????“is-a(??)”??????? ??: “??????”; “?????”? ?:???????????????????(??),?????????????? ?????????: ??????????,?????????????

46. ???????????

47. ????????????????? 1 ????: ???????????,??????????????????????? 2 ??????: (1)????????: ??.?????? ?? ???.?????? (2)??????????: ???.???????? 3 ?????: (1)???????????????????,????????????????; (2)??????????????????????????????? 4 ????? (1)?????????; (2)???????????

48. 4.1.7 ??????????1 ????? (1)??????????????????,????????????????? (2)public?????public????????????????????? (3)final?????final?????????????????????,????????? (4)abstract?????abstract??????????????????????????,?????????,?????????

49. 4.1.7 ??????????2 ??????? (1)public???? (2)private???? (3)protected???? (4)????(???)? ???????????????: (1)abstract???final????????? (2)abstract???private,static,final?native?????????? (3)abstract?????private???(???????)? (4)abstract????????static???

50. 4.1.8?????4-3?

53. 4.1.9 ?????? ?????????Java?????? ????????,???????,????????,?????????:API---application program interface SUN ?????????????JFC?

54. ??????? ?????????????????,??import?????????????,?????????????????????????????Java???,????Java?????????????????????

55. ???????????

56. ?????????? 1) java.lang 2) java.lang.reflect 3) java.io 4) java.util 5) java.util.zip 6) java.awt 7) java.awt.image 8) java.awt.datatransfer 9) java.awt.event

57. ?????????? 10) java.applet 11) java.net 12) java.corba 13) java.corba.orb 14) java.rmi 15) java.rmi.reistry 16) java.rmi.server 17) java.security 18) java.security.acl 19) java.security.interfaces 20) java.sql

58. ??java???? ? ??????? ? ??????? java.applet applet java.rmi ?????? java.awt ????????? java.rmi.dgc ??java.rmi java.awt.datatranster ??????? java.rmi.registry ?? java.awt.event ???? java.rmi.server ?? java.awt.image ???? java.security ?? java.awt.peer ?????? java.security.acl ??java.security java.beans ???? java.security.interfaces ?? java.io ???? java.sql ??? java.lang ??????? java.text ??? java.lang.reflect ??(“??”) java.util ???? java.math ???????? java.util.zip ?????? java.net ??

59. ??javax???? ? ????????? javax.accessibility ???? javax.swing “??”???????? javax.swing.border ???? javax.swing.colorchooser ???? javax.swing.event ??java.awt.event????? javax.swing.filechooser ???? javax.swing.plaf ????????? javax.swing.plaf.basic ???????? javax.swing.plaf.metal ???????? javax.swing.plaf.multi ????????? javax.swing.table ??????? javax.swing.text ???????? javax.swing.text.html HTML?? javax.swing.text.rtf RTF(Rich Text Format)?? javax.swing.tree ??????? javax.swing.undo ??????????

60. ???????????? 1 ????? ?:??Java Applet?????Java.applet ?? Applet????? 2 ??????? ?:??????????????? System.out.println( ) 3 ???????? ?:????????????????? TextField input ?3???,?????????3???,????????