Thread: What's wrong with my code :(

Can someone help me about my system. Im having trouble about my code. I cant figure out how it works. Lets see. Soo its about File class. How am i be able to compare string to notepad data. I've tried this code:

import java.util.*;
import java.io.*;
import java.io.File;
 
public class DeleteF {
    Scanner in = new Scanner(System.in);
    File file = new File("C:\\Documents and Settings\\user\\My Documents"
            + "\\NetBeansProjects\\StudentInformation\\src\\information.txt");
 
    ArrayList store = new ArrayList();
    String idM, record, id, temp;
    int match = 0;
 
 
    public void delete() throws Exception{
        Scanner inFile = new Scanner(file);
        inFile.useDelimiter("#");
 
        System.out.print("ID: ");
        idM = in.nextLine();
 
 
        while(inFile.hasNext()){
              record = inFile.nextLine();
//            System.out.println(record);
 
              if(inFile.hasNext()){
                  inFile.nextLine();
 
                if(idM.equals(inFile.next())){
                 System.out.println("LOL");        
                 }
 
                else{           
                    System.out.println("No records found!");
 
                  }
 
 
              }
 
 
              store.add(record);
 
        }//end of while
 
 
        for(int x = 0; x < store.size(); x++){
            System.out.println(store.get(x));
 
 
        }
 
 
 
    }//end of delete()
 
 
}//end of DeleteF class

My problem is, the user should enter an existing ID. And when it matches to the ID from the notepad, it will be deleted ..



1.JPG

Can you train the user so he only enters good data? How does the user know what good data is? Should the program display all the IDs and allow the user to chose one?

sorry. i've just joined today.

The output for that is:

[1] Add
[2] Delete
[3] Edit
[4] View
[5] Exit

choice: _____


the user will choose from the following menu. and im currently working at the DELETE FUNCTION. on the delete function, the user will input an ID which is already existed on the notepad that he wants to delete.

example:

This is the data on the notepad.
1.JPG

the user wanted to delete the 1#Zsannen Mariano#3rd Year#, he will enter the ID number. which is number 1. and when he enter it, the whole information the ID number 1 will be deleted. the main menu:

[1] Add
[2] Delete
[3] Edit
[4] View
[5] Exit

choice: _____

will prompt again and ask the user to choose. if he choose number 4 - VIEW .. the data from the notepad will be displayed and the deleted data earlier will not be included on the notepad.


Hope you understand my explanation

and i've edited the code.

import java.util.*;
import java.io.*;
import java.io.File;
import java.io.PrintWriter;
 
public class DeleteF {
    Scanner in = new Scanner(System.in);
    File file = new File("C:\\Documents and Settings\\user\\My Documents"
            + "\\NetBeansProjects\\StudentInformation\\src\\information.txt");
 
    ArrayList store = new ArrayList();
    String idM, record, id, temp;
    int match = 0;
 
 
    public void delete() throws Exception{
        Scanner inFile = new Scanner(file);
        inFile.useDelimiter("#");
 
        System.out.print("ID: ");
        idM = in.nextLine();
 
 
        while(inFile.hasNext()){
              record = inFile.nextLine();
//            System.out.println(record);
 
                if(inFile.hasNext()){
                    inFile.nextLine();
 
                    if(idM.equals(inFile.next())){
                    System.out.println(inFile.next());  
                    }
 
                    else{
                    store.add(record);
                    }
                }//end of checking line condition
        }//end of while
 
        file.delete();
 
        file.createNewFile();
        PrintWriter pw = new PrintWriter(file);
 
 
        for(int x = 0; x < store.size(); x++){
            pw.print(store.get(x));
            pw.println();
 
 
        }
 
 
        pw.close();
 
    }//end of delete()
 
 
}//end of DeleteF class

1.JPG -- FIRST 2.JPG -- SECOND

The main method is in another class. The add, delete, edit, view and exit functions are just methods that has been called on the main class. I've separated it and instantiate it on the main.