Styjun

I'm getting an error when trying to run this program (editing & deleting content in csv file).
Error:

Exception in thread "main" java.util.InputMismatchException
 at java.util.Scanner.throwFor(Scanner.java:864)
 at java.util.Scanner.next(Scanner.java:1485)
 at java.util.Scanner.nextDouble(Scanner.java:2413)
 at project.AnimalManager.loadFromFile(AnimalManager.java:88)
 at project.Test.main(Test.java:10)

Main App

package project;


public class Test 

 public static void main(String[] ages) 

 //Load file 
 AnimalManager aMgr = new AnimalManager();
 aMgr.loadFromFile("AnimalDetails.txt");

// try 
// Animals anim = aMgr.getAnimalById("48331827032019");
// aMgr.deleteAnimal(anim);
// catch (IllegalArgumentException exc) 
// System.out.println(exc);
// 

 System.out.println("Edit Animal:");

 boolean edited = aMgr.editAnimal("48331827032019",5,"German","200","Huskies","Huskies","n","n",1000.0,"John"); //By ID
 if (edited) 
 System.out.println("Animal has been edited successfully.");
 else 
 System.out.println("Animal not found (test failed).");

 

Animal Manager

package project;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Scanner;





public class AnimalManager 

 private final ArrayList<Animals> animalList;

 public AnimalManager() 
 this.animalList = new ArrayList<>();
 

 public boolean addAnimal(Animals a) 
 if (a == null)
 throw new IllegalArgumentException("Animal argument is null");

 if(animalList.contains(a))
 return false;
 animalList.add(a);
 return true;
 

 public void deleteAnimal (Animals a) 
 if (a == null)
 throw new IllegalArgumentException("Animal argument is null");

 animalList.remove(a);
 

 public Animals getAnimalById(String ID) 
 for (Animals a : this.animalList) 
 if (a.getID().equals(ID))
 return a; 
 
 return null;
 

 public boolean editAnimal(String ID, int age, 
 String breed, String breedPurity, String motherBreed, String fatherBreed, String medicalHistory, String identification, double price, String owner) 


 //Load from file
 public void loadFromFile(String filename) 
 try 
 Scanner sc = new Scanner(new File(filename));

 sc.useDelimiter("[,rn]+");
 //animal details: id,age,breed,purity of breed,mother breed,father breed,medical history, identification, price, owner

 while(sc.hasNext()) 
 String ID = sc.next();
 int age = sc.nextInt();
 String breed = sc.next();
 String breedPurity = sc.next();
 String motherBreed = sc.next();
 String fatherBreed = sc.next();
 String medicalHistory = sc.next();
 String identification = sc.next();
 double price = sc.nextDouble();
 String owner = sc.next();

 animalList.add(new Animals(ID, age, breed, breedPurity, motherBreed, fatherBreed, medicalHistory, identification, price, owner ));

 
 sc.close();

 catch (IOException e) 
 System.out.println("Exception thrown. " + e);
 




 public void saveToFile(String filename) 

 StringBuilder output = new StringBuilder(); // To store all passengers info.

 for (Animals p : animalList) // Loop through the passengers to store
 // every passenger as the line of strings to add them to the file.
 output.append(p.getID()).append(",").append(p.getAge()).append(",").append(p.getBreed()).append(",")
 .append(p.getMother()).append(",").append(p.getFather()).append(",").append(p.getMedical()).append(",")
 .append(p.getIdenti()).append(",").append(p.getPrice()).append(",").append(p.getOwner()).append("rn");
 

 try (FileWriter fw = new FileWriter(new File(filename))) 
 fw.write(output.toString());
 catch (Exception e) 
 System.out.println("Passengers cannot be saved: " + e);
 

 

 public String toString() 
 // use String if more comfortable with it - StringBuilding faster for concat
 // than (immutable) String
 StringBuilder strBuilder = new StringBuilder();
 for (Animals p : this.animalList) 
 strBuilder.append(p.toString()).append("n");
 

 return strBuilder.toString();
 

The idea here is to provide the specific animal ID which you want to edit and write down the new information to replace the old one. I already have the save to file method and I think thats where the issue is coming from.

CSV

0,2,AmercianShorthair,100,AmercianShorthair,AmercianShorthair,y,y,900.0,Ann
3,4,GermanShepherd,100,GermanShepherd,GermanShepherd,no,yes,600.0,Dave
6,3,Poodle,100,Poodle,Poodle,yes,no,300.0,Dianna
456,4,Azawakh,50,Unknown,Azawakh,no,no,300.0,April
25041019042018,1,Vizsla,50,Vizsla,TreeingTennesseeBrindle,no,yes,500.0,Lex
3271,1,Beagle,50,Beagle,Unknown,no,no,200.0,Blanton
48331827032019,33,sheperd,50,50,50,no,yes,300.0,Mike

The CSV should contain commas at the end like so:

0,2,AmercianShorthair,100,AmercianShorthair,AmercianShorthair,y,y,900.0,Ann,
3,4,GermanShepherd,100,GermanShepherd,GermanShepherd,no,yes,600.0,Dave,
6,3,Poodle,100,Poodle,Poodle,yes,no,300.0,Dianna,
456,4,Azawakh,50,Unknown,Azawakh,no,no,300.0,April,
25041019042018,1,Vizsla,50,Vizsla,TreeingTennesseeBrindle,no,yes,500.0,Lex,
3271,1,Beagle,50,Beagle,Unknown,no,no,200.0,Blanton,
48331827032019,33,sheperd,50,50,50,no,yes,300.0,Mike

Notice the commas at the end of the lines. What is happening, is it is going to the next line immediately and combining the name with the number at the beginning. For example, "Ann3,4" because linebreaks aren't delimiters in this case.

Also in the CSV, you misspelled Shepherd.

Since the delimiter is not new lines, it is the equivalant of this:

0,2,AmercianShorthair,100,AmercianShorthair,AmercianShorthair,y,y,900.0,Ann3,4,GermanShepherd,100,GermanShepherd,GermanShepherd,no,yes,600.0,Dave6,3,Poodle,100,Poodle,Poodle,yes,no,300.0,Dianna456,4,Azawakh,50,Unknown,Azawakh,no,no,300.0,April25041019042018,1,Vizsla,50,Vizsla,TreeingTennesseeBrindle,no,yes,500.0,Lex3271,1,Beagle,50,Beagle,Unknown,no,no,200.0,Blanton48331827032019,33,sheperd,50,50,50,no,yes,300.0,Mike

Notice how it says 900.0, Ann3, 4, etc. it shifts it all by one so you aren't actually reading in 600.0 as the double, you are reading in Dave as the double.

Edit the code like so:

 for (Animals p : animalList) // Loop through the passengers to store
 // every passenger as the line of strings to add them to the file.
 output.append(p.getID()).append(",").append(p.getAge()).append(",").append(p.getBreed()).append(",")
 .append(p.getMother()).append(",").append(p.getFather()).append(",").append(p.getMedical()).append(",")
 .append(p.getIdenti()).append(",").append(p.getPrice()).append(",").append(p.getOwner()).append(",").append("rn"); //add another append between getOwner and rn
 

Note this is where you are adding animals to the CSV. Here, for each animal, you now append a comma at the end of each line as well. The ed is between appending getOwner and appending the rn.

@JustAFellowCoder has told you a solution to your problem but in my opinion using a CVS file for that is not the best idea.

How about using java.util.Properties?
It is very simple and will fix all your problems, you can just do the following:

//Your file path
 Path path = Paths.get("Animal.properties");

 //Create a new properties and store it in a file
 Properties properties = new Properties();
 //your id
 int id = 1;
 //Everything in properties must be saved as Strings
 properties.setProperty("Id", String.valueOf(id));
 properties.store(Files.newOutputStream(path), null);

 //new properties
 properties = new Properties();
 properties.load(Files.newInputStream(path));
 System.out.println("Id: " + properties.getProperty("Id"));

And you will get a "Animal.properties" file which can be easily restored and a console printing "Id: 1".