Question

How can I write a separate java class to change a given name or a given email of a user that was already saved (keep in mind that there may be numerous names and emails).

Note: It should change the name or email that is saved in the txt file.

Here is my code so far:

User class

public class User {
    private String fName;
    private String lName;
    private String UserEmail;

    public User(String firstName, String lastName, String email) {
        this.fName = firstName;
        this.lName = lastName;
        this.UserEmail = email;
    }

    //constructor used to load saved profile information.
    public User(String firstName, String lastName, String email, double income, double expenses) {
        this.fName = firstName;
        this.lName = lastName;
        this.UserEmail = email;
    }

    public String getFirstName() {

        return fName;
    }

    public String getLastName() {

        return lName;
    }

    public String getEmail() {

        return UserEmail;
    }


    public void setFirstName(String firstName) {

        this.fName = firstName;
    }

    public void setLastName(String lastName) {

        this.lName = lastName;
    }

    public void setEmail(String email) {

        this.UserEmail = email;
    }


    @Override
    public String toString() {
        return
                fName +
                        ", " + lName +
                        ", " + UserEmail ;
    }
}

Profile Create class

import java.io.IOException;
import java.util.Scanner;

public class ProfileCreate {

    public User createUser() throws IOException {
        String fName;
        String lName;
        String email;

        Scanner read = new Scanner(System.in);

        System.out.println("First name?");
        fName = read.nextLine();

        System.out.println("Last name?");
        lName = read.nextLine();

        System.out.println("Email?");
        email = read.nextLine();

        System.out.println("Successful Profile Creation");

        User x = new User(fName, lName, email);
        return x;


    }
}

Save User Info class

import java.util.Scanner;
import java.io.*;
import java.util.*;
import java.lang.*;

public class SaveUserInfo {
    public void writeDetails(String saveDetails) throws IOException{


        FileWriter out = new FileWriter("Details.txt");

        for (int x = 0; x < saveDetails.length(); x++){
            out.write(saveDetails.charAt(x));
        }

        out.close();

    }
}

Answer 1

import java.io.IOException;

import java.util.Scanner;

public class UserProfile

{

static int menu()

{

Scanner sc = new Scanner(System.in);

System.out.print("\n\n ************* MENU ************* ");

System.out.print("\n 1 - Change Name.");

System.out.print("\n 2 - Change Email.");

System.out.print("\n What is your choice? ");

return sc.nextInt();

}

static int searchName(User users[], String name)

{

for(int c = 0; c < users.length; c++)

if(users[c].getFirstName().equalsIgnoreCase(name))

return c;

return -1;

}

static int searchEmail(User users[], String email)

{

for(int c = 0; c < users.length; c++)

if(users[c].getFirstName().equalsIgnoreCase(email))

return c;

return -1;

}

static void change(User users[], int ch)

{

int found = -1;

Scanner sc = new Scanner(System.in);

switch(ch)

{

case 1:

System.out.print("\n Enter old first name to change: ");

String name = sc.nextLine();

found = searchName(users, name);

if(found == -1)

System.out.print("\n Name not available in the list.");

else

{

System.out.println("First name?");

String fName = sc.nextLine();

System.out.println("Last name?");

String lName = sc.nextLine();

users[found].setFirstName(fName);

users[found].setFirstName(lName);

}

break;

case 2:

System.out.print("\n Enter old first name to change: ");

String email = sc.nextLine();

found = searchName(users, email);

if(found == -1)

System.out.print("\n Email not available in the list.");

else

{

System.out.println("\n Enter new Email: ");

String newEmail = sc.nextLine();

  

users[found].setEmail(newEmail);

}

break;

default:

System.out.println("\n Invalid choice!!");

}

}

public static void main(String ss[])throws IOException

{

User users[] = new User[3];

ProfileCreate pc = new ProfileCreate();

SaveUserInfo sui = new SaveUserInfo();

String saveDetails = "";

for(int c = 0; c < users.length; c++)

{

users[c] = pc.createUser();

if(c == users.length - 1)

saveDetails += users[c].toString();

else

saveDetails += users[c].toString() + "\n";

}

System.out.println(saveDetails);

sui.writeDetails(saveDetails);

change(users, menu());

}

}