[IP Detection Program] IP 클래스 구분/식별 코드 in Java

IP Address Classes A-E

IP 주소의 다섯 클래스 A~E, 이를 분류해보자.

http://www.pracspedia.com/IT-Sem%204/CN-ipclassdetection.html

네트워크 관련 과제 중 멀티캐스트와 유니캐스트를 각기 다른 소켓으로 다루기 위해 찾았던 코드인데,

32개의 이진수로 표시되는 IP주소를 이용해 클래스를 구분한다.

1. /*
2. Program for IP (Internet Protocol) Class Detection in Java
3. Author: Khushang Mehta Author Link: https://www.facebook.com/khushang.mehta
4. www.pracspedia.com
5. */
6. class IpClassDetection
7. {
8. public static void main(String args[])
9. {
10. int ip[]=new int[4];
11. int i=0,j=0,k=0,remainder;
12. String bin;
13. while(j!=3)
14. {
15. while(i < args[0].length() && args[0].charAt(i++)=='.')
16. {
17. ip[j++]=Integer.parseInt(args[0].substring(k,i-1));
18. k=i;
19. }
20. }
21. ip[j++]=Integer.parseInt(args[0].substring(k,args[0].length()));
22. if(ip[0] >-1 &&ip[0] < 256 && ip[1] > -1 && ip[1] < 256 && ip[2] > -1 && ip[2] < 256 && ip[3] > -1 && ip[3] < 256)
23. {
24. System.out.println("Ip is valid");
25. bin=Integer.toBinaryString(ip[0]);
26. if(bin.charAt(0)=='0')
27. {
28. System.out.println("The Ip entered is a Class A Address");
29. System.out.println("Net ID :- "+ip[0]);
30. System.out.println("Host ID :- "+ip[1]+"."+ip[2]+"."+ip[3]);
31. }
32. else
33. {
34. if(bin.charAt(1)=='0')
35. {
36. System.out.println("The Ip entered is a Class B Address");
37. System.out.println("Net ID :- "+ip[0]+"."+ip[1]);
38. System.out.println("Host ID :- "+ip[2]+"."+ip[3]);
39. }
40. else
41. {
42. if(bin.charAt(2)=='0')
43. {
44. System.out.println("The Ip entered is a Class C Address");
45. System.out.println("Net ID :- "+ip[0]+"."+ip[1]+"."+ip[2]);
46. System.out.println("Host ID :- "+ip[3]);
47. }
48. else
49. {
50. if(bin.charAt(3)=='0')
51. System.out.println("The Ip entered is a Class D Address");
52. else
53. System.out.println("The Ip entered is a Class E Address");
54. }
55. }
56. }
57. }
58. else
59. System.out.println("Ip is invalid");
60. }
61. }
62. /*
63. Output :-
64. C:\Users\Student>java IpClassDetection 172.17.16.256
65. Ip is invalid
66.  
67. C:\Users\Student>java IpClassDetection 172.17.16.52
68. Ip is valid
69. The Ip entered is a Class B Address
70. Net ID :- 172.17
71. Host ID :- 16.52
72. */

IpClassDetection.java