Create a HashTable for this PhoneBook class in Java:

Info:

PhoneBook, which represents the phone book. The class should contain a hash table as a datafield. This table contains the people in the book. The phone book should contain the add,delete, find, change, quit, save and restore methods.

HashTable, which is the ADT HashTable. This is the class which contains the PhoneBooks collection of data (all of the People objects in the PhoneBook), as well as the operations which can be performed on that collection of data.

My PhoneBook class:

public class People {

String Name; Integer Phone; People(int Phone,String Name ){ this.Phone=Phone; this.Name=Name; } public String getName() { return Name; } public void setName(String name) { Name = name; } public int getPhone() { return Phone; } public void setPhone(int phone) { Phone = phone; } }

Then create the Phone book class, which is going to use the above People class as value and phone number as the key in the HashMap entries.

import java.security.KeyStore.Entry; import java.util.HashMap;

public class PhoneBook { HashMap phonebook=new HashMap(); HashMap delete_phonebook=new HashMap(); //For restoring the deleted entries PhoneBook(){ // Adding sample data phonebook.put(57371,new People(57371,"Jack")); phonebook.put(57431,new People(57431,"John")); phonebook.put(57577,new People(57577,"Ronny")); phonebook.put(57583,new People(57583,"Johnny")); phonebook.put(51577,new People(51577,"Samuel")); phonebook.put(24177,new People(24177,"Nathan")); } public void add(Integer num,People p ){ phonebook.put(num,new People(num,"Ronny")); } public void save(Integer num, People p){ phonebook.put(num, p); } //Delete by number public void delete(Integer num){ //Storing the entry first in delete_phonebook People temp=this.find(num); delete_phonebook.put(num, temp); phonebook.remove(num); } // Delete by Name public void delete(String name){ People temp=this.find(name); // Searching by name in the below mthod Integer delPhone=temp.getPhone(); delete(delPhone); //Calling the above delete method for removal } //Different types of find method, this one based on phone number as input key public People find(Integer num){ return phonebook.get(num); } //Find mrthod based on Name public People find(String name){ for(java.util.Map.Entry entry : phonebook.entrySet()){ if(entry.getValue().getName().equals(name)){ return entry.getValue(); } } return null; } public void changeName(Integer num,String newName){ People temp=this.find(num); temp.setName(newName); phonebook.remove(num); // Removing the old entry phonebook.put(num,temp); //Saving the new entry with updated Name } public void changeNumber(Integer newnum,String name){ People temp=this.find(name); Integer oldNum=temp.getPhone(); temp.setPhone(newnum); phonebook.remove(oldNum); // Removing the old entry phonebook.put(newnum,temp); } public void restore(String name){ for(java.util.Map.Entry entry : delete_phonebook.entrySet()){ if(entry.getValue().getName().equals(name)){ Integer delnum=entry.getValue().getPhone(); People temp=delete_phonebook.get(delnum); Integer res_num=temp.getPhone(); phonebook.put(res_num, temp); } } }

}

Basic HashTable format example that I would like to use:

public class HashTableDemo { public static void main(String args[]) { // Create a hash map Hashtable b = new Hashtable(); names; String gg; name.put("Name", new Double(0004.34)); name.put("Name", new Double(100.002)); name.put("Name", new Double(1008.00)) // Show all anme in hash table. names = balance.keys(); while(names.hasMoreElements()) { gg = (String) names.nextElement(); System.out.println(gg + ": " + name.get(gg)); } System.out.println(); } }