IT management

Question: AVL & Hashing in JAVA LANGUAGE PLEASE :) Building a data structure for countries visa applications data Step 1: build a sample data file that contains countries visa applications records in the following format: Country_Nme / Country_VISA_related_data_file_name (e.g. Germany / Germany.txt ) Step 2: using the data file created in step 1, build an AVL tree of countries nodes (use country name as key). Step 3: implement the following functions on countries AVL tree:  Print out countries sorted.  Search for a specific country  Insert a new country record.  Delete a specific country record.  Calculate tree height.  Save Tree back to file. Step 4: using the Country_VISA_related_data_file_name that stored in each tree country node, load the visa data that stored in each file. The visa record data format in these files is as follow: Passport_#/Full_name/Age/Gender/ Intended_date_of_arrival/ Intended_date_of_departure (e.g. 289332/Mamoun Nawahdah/40/M/26\4\2016/2\5\2016) Step 4: create a Hash Table using the country visa data from step 4. Step 5: implement the following functions on country visa hash table:  Print hashed table (including empty spots).  Print out table size.  Print out used hash function.  Insert a new visa record to hash table.  Search for a specific visa record.  Delete a specific visa record.  Save hash table back to file. thank you :)

ANSWER

1.  import java.util.Scanner;
   

3.  /* Class AVLNode */
   

4.  class AVLNode
   

5.  {    
   

6.      AVLNode left, right;
   

7.      int data;
   

8.      int height;
   

10.      /* Constructor */
    

11.      public AVLNode()
    

12.      {
    

13.          left = null;
    

14.          right = null;
    

15.          data = 0;
    

16.          height = 0;
    

17.      }
    

18.      /* Constructor */
    

19.      public AVLNode(int n)
    

20.      {
    

21.          left = null;
    

22.          right = null;
    

23.          data = n;
    

24.          height = 0;
    

25.      }     
    

26.  }
    

28.  /* Class AVLTree */
    

29.  class AVLTree
    

30.  {
    

31.      private AVLNode root;     
    

33.      /* Constructor */
    

34.      public AVLTree()
    

35.      {
    

36.          root = null;
    

37.      }
    

38.      /* Function to check if tree is empty */
    

39.      public boolean isEmpty()
    

40.      {
    

41.          return root == null;
    

42.      }
    

43.      /* Make the tree logically empty */
    

44.      public void makeEmpty()
    

45.      {
    

46.          root = null;
    

47.      }
    

48.      /* Function to insert data */
    

49.      public void insert(int data)
    

50.      {
    

51.          root = insert(data, root);
    

52.      }
    

53.      /* Function to get height of node */
    

55.    "4. check empty");
    

56.             System.out.println("5. clear tree");
    

58.             int choice = scan.nextInt();            
    

59.             switch (choice)
    

60.             {
    

61.             case 1 : 
    

62.                 System.out.println("Enter integer element to insert");
    

63.                 avlt.insert( scan.nextInt() );                     
    

64.                 break;                          
    

65.             case 2 : 
    

66.                 System.out.println("Enter integer element to search");
    

67.                 System.out.println("Search result : "+ avlt.search( scan.nextInt() ));
    

68.                 break;                                          
    

69.             case 3 : 
    

70.                 System.out.println("Nodes = "+ avlt.countNodes());
    

71.                 break;     
    

72.             case 4 : 
    

73.                 System.out.println("Empty status = "+ avlt.isEmpty());
    

74.                 break;     
    

75.             case 5 : 
    

76.                 System.out.println("\nTree Cleared");
    

77.                 avlt.makeEmpty();
    

78.                 break;         
    

79.             default : 
    

80.                 System.out.println("Wrong Entry \n ");
    

81.                 break;   
    

82.             }
    

83.             /*  Display tree  */ 
    

84.             System.out.print("\nPost order : ");
    

85.             avlt.postorder();
    

86.             System.out.print("\nPre order : ");
    

87.             avlt.preorder();
    

88.             System.out.print("\nIn order : ");
    

89.             avlt.inorder();
    

91.             System.out.println("\nDo you want to continue (Type y or n) \n");
    

92.             ch = scan.next().charAt(0);                        
    

93.         } while (ch == 'Y'|| ch == 'y');               
    

94.     }
    

95.  }