Could someone edit my code? The readFromFile() method should check is a file nam

ID: 3574215 • Letter: C

Question

Could someone edit my code?

The readFromFile() method should check is a file named "data" exists, and if it does, new information is added on to the existing file. If it does not exist, it creates a new file named "data" and writes new information into the file.

Also, in the getPerson method in the Main class, instead of returning a new constructor Person(String x, etc...), call the setFirstName(), setLastName(), set...() methods from the class Person.

import java.util.ArrayList;
import java.util.Scanner;

/**
* Main class tests the class ContactList by getting the input from the user and saves the program, adds a new contact
* list, reads the contact from file, show contact by inputting the last name, or shows all contract based on the input
* from the user.
*
* @author Jae
* @produced 11/30/16
* @version 2.0
*/
public class Main {
public static void main(String[] args) {

int option = 5;

       //creates an object of each of the other classes,
       ContactList list = new ContactList();
       Scanner scanner = new Scanner(System.in);
       String lastName;
       String fileName = "data";
       list.readFromFile(fileName);

       System.out.println("Welcome to contact list manager!");
       //calls each method on each of the objects it creates, and
       while (option != 0) {

           System.out.println("0. Quit the program");
           System.out.println("1. Add new person to contact list");
           System.out.println("2. Show contact by last name");
           System.out.println("3. Show all contact");
           System.out.print("Enter your option: ");

option = Integer.parseInt(scanner.nextLine());

           switch (option) {
               case 0:
                   list.saveToFile(fileName);
                   System.out.println("Contact list has been saved! Exiting program now.");
                   break;
               case 1:
                   list.addPerson(getPerson(scanner));
                   break;
               case 2:
                   System.out.print("Enter a last name to search for: ");
                   lastName = scanner.nextLine();
                   list.showPersonByLastName(lastName);
                   break;
               case 3:
                   System.out.println("Contact List:");
                   list.printContactList();
                   break;
           }
       }
   }

/**
* get person's information from user
*
* @param scanner input stream
* @return a person
*/

   private static Person getPerson(Scanner scanner) {
       String firstName;
       String lastName;
       String streetAddress;
       String emailAddress;
       String phoneNumber;
       String note;

       System.out.print("Enter first name: ");
       firstName = scanner.nextLine();
       System.out.print("Enter last name: ");
       lastName = scanner.nextLine();
       System.out.print("Enter street address: ");
       streetAddress = scanner.nextLine();
       System.out.print("Enter email address: ");
       emailAddress = scanner.nextLine();
       System.out.print("Enter phone number: ");
       phoneNumber = scanner.nextLine();
       System.out.print("Enter note: ");
       note = scanner.nextLine();

       return new Person(firstName, lastName, streetAddress, emailAddress, phoneNumber, note);
       }
}

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

/**
* creates a resizable(grows as it exceeds the size) array of objects, Person. This class is able to add the person's
* information to Person, print all the contact list in it, retrieve the person's information by last name, save to the
* file if methods are called.
*
* @author Jae
* @produced 11/25/16
* @version 1.0
*/
public class ContactList {

   private ArrayList<Person> list;

   /**
   * constructor
   */
   public ContactList() {
       list = new ArrayList<>();
   }

   /**
   * check the Person p it cannot be null its lastName field cannot be blank
   * it will be added to the contact list in order of last name when all
   * condition are met
   *
   *
   * @param p
   */
   public void addPerson(Person p) {
if (p != null && p.getLastName() != null) {
boolean added = false;
for (int i = 0; i < list.size(); i++) {
if (p.compareTo(list.get(i)) < 0 ) {
list.add(i, p);
added = true;
break;
}
}
if (added == false) {
list.add(p);
}
}
   }

   /**
   * Prints all information about all contacts to the console, sorted by last
   * name first then their first name
   */
public void printContactList() {
for (Person person : list) {
System.out.println(person);
}
}

/**
* Retrieve and display all information of people whose last name match with
* lastName
*
* @param lastName
*/
public void showPersonByLastName(String lastName) {
if (lastName != null) {
for (Person person : list) {
if (lastName.equals(person.getLastName())) {
System.out.println(person);
}
}
}
}

   /**
   * Save the current contact list to disk at fileName
   *
   * @param fileName
   */
   public void saveToFile(String fileName) {
try {
FileWriter fw = new FileWriter(fileName);
String line;
for (Person p : list) {
line = " " + p.getFirstName()
+ ", " + p.getLastName()
+ ", " + p.getStreetAddress()
+ ", " + p.getEmailAddress()
+ ", " + p.getPhoneNumber()
+ ", " + p.getNote()
+ System.lineSeparator();
fw.write(line);
}
fw.close();
} catch (IOException ex) {
System.err.println(ex.getMessage());
}
}

   /**
   * Read the current contact list from disk at fileName
   *
   * @param fileName
   */
   public void readFromFile(String fileName) {

   }
}

/**
* The class Person sets the information of the individual to each of the String with its methods, and orders the list by
* last name alphabetically.
*
* @author Jae
* @produced 11/25/16
* @version 1.0
*/
public class Person implements Comparable<Person>{

   private String firstName;   //private member variable
   private String lastName;   //private member variable
   private String streetAddress;   //private member variable
   private String emailAddress;   //private member variable
   private String phoneNumber;   //private member variable
   private String note;   //private member variable

   /**
   * constructor
   */
   public Person() {
this.firstName = null;
this.lastName = null;
this.streetAddress = null;
this.emailAddress = null;
this.phoneNumber = null;
this.note = null;
   }

   /**
   * constructor
   * @param firstName
   * @param lastName
   * @param streetAddress
   * @param emailAddress
   * @param phoneNumber
   * @param note
   */
   public Person(String firstName, String lastName, String streetAddress, String emailAddress, String phoneNumber, String note) {
this.firstName = firstName;
this.lastName = lastName;
this.streetAddress = streetAddress;
this.emailAddress = emailAddress;
this.phoneNumber = phoneNumber;
this.note = note;
   }


   /**
   * get first name
   * @return first name
   */
   public String getFirstName() {
       return firstName;
   }

   /**
   * get last name
   * @return last name
   */
   public String getLastName() {
       return lastName;
   }

   /**
   * get street address
   * @return street address
   */
   public String getStreetAddress() {
       return streetAddress;
   }

   /**
   * get email address
   * @return email address
   */
   public String getEmailAddress() {
       return emailAddress;
   }

   /**
   * get phone number
   * @return phone number
   */
   public String getPhoneNumber() {
       return phoneNumber;
   }

   /**
   * get note
   * @return note
   */
   public String getNote() {
       return note;
   }

   /**
   * set value for first name to firstName
   * @param firstName
   */
   public void setFirstName(String firstName) {
       this.firstName = firstName;
   }

   /**
   * set value for last name to lastName
   * @param lastName
   */
   public void setLastName(String lastName) {
       this.lastName = lastName;
   }

   /**
   * set value for street address to streetAddress
   * @param streetAddress
   */
   public void setStreetAddress(String streetAddress) {
       this.streetAddress = streetAddress;
   }

   /**
   * set value for email address to emailAddress
   * @param emailAddress
   */
   public void setEmailAddress(String emailAddress) {
       this.emailAddress = emailAddress;
   }

   /**
   * set value for phone number to phoneNumber
   * @param phoneNumber
   */
   public void setPhoneNumber(String phoneNumber) {
       this.phoneNumber = phoneNumber;
   }

   /**
   * set value for note to note entered
   * @param note
   */
   public void setNote(String note) {
       this.note = note;
   }

   /**
   * Returns the String representation of values for all attributes of the Person that calls it.
   * @return
   */
   public String toString() {
       return "Name: " + firstName + " " + lastName +
               " Address: " + streetAddress +
               " Email: " + emailAddress +
               " Phone#: " + phoneNumber +
               " Note: " + note;
   }

   /**
   * compares 2 people
   * @param o
   * @return the difference between their last name and their first name
   */
   public int compareTo(Person x) {
if (x == null) {
return 1;
}
int comp = lastName.compareTo(x.lastName);
if (comp == 0) {
if (firstName == null) {
return -1;
}
return firstName.compareTo(x.firstName);
}
return comp;
}
}

Explanation / Answer

import java.util.ArrayList;
import java.util.Scanner;

int option = 5;

option = Integer.parseInt(scanner.nextLine());

/**
* get person's information from user
*
* @param scanner input stream
* @return a person
*/

Person p1=new Person();

p1.setFirstName(first Name);

p1.setLastName(lastName);

p1.setStreetAddress(streetAddress);

p1.setEmailAddress(emailAddress);

p1.setPhoneNumber(phoneNumber);

p1.setNote(note);

return p1;
}
}

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

    Boolean bool=false;

   /**
   * constructor
   */
   public ContactList() {
       list = new ArrayList<>();
   }

   /**
   * Save the current contact list to disk at fileName
   *
   * @param fileName
   */
   public void saveToFile(String fileName) {
try {

FileWriter fw = new FileWriter(fileName);
String line;
for (Person p : list) {
line = " " + p.getFirstName()
+ ", " + p.getLastName()
+ ", " + p.getStreetAddress()
+ ", " + p.getEmailAddress()
+ ", " + p.getPhoneNumber()
+ ", " + p.getNote()
+ System.lineSeparator();
fw.write(line);
}
fw.close();
} catch (IOException ex) {
System.err.println(ex.getMessage());
}
}

   /**
   * Read the current contact list from disk at fileName
   *
   * @param fileName
   */
   public void readFromFile(String fileName) {

File f=new File(filename);

Bool=f.exists();

if(bool==false) {

System.out.println(“file”+fileName+”not exists”);

f.createNewFile();

System.out.println(“new file named”+fileName+”created”);

}

BufferedReader br = null;

FileReader fr = null;

Person p2=new Person();

fr = new FileReader(FILENAME);

br = new BufferedReader(fr);

String sCurrentLine;

br = new BufferedReader(new FileReader(FILENAME));

while ((sCurrentLine = br.readLine()) != null) {

int sum=0;

Scanner obj=new Scanner(System.in);

StringTokenizer st=new StringTokenizer(sCurrentLine," ");

while(st.hasMoreTokens())

{

p2.setFirstName(st.nextToken());

p2.setLastName(st.nextToken());

p2.setStreetAddress(st.nextToken());

p2.setEmailAddress(st.nextToken());

p2.setPhoneNumber(st.nextToken());

p2.setNote(st.nextToken());

}

addPerson(p2);

}