Thread: reading string in from text file

Hey Guys... im getting an error could you help?

 

Exception in thread "main" java.lang.NumberFormatException: For input string: "bogus"

	at java.lang.NumberFormatException.forInputString(Num  berFormatException.java:48)

	at java.lang.Integer.parseInt(Integer.java:449)

	at java.lang.Integer.parseInt(Integer.java:499)

	at lab10.main(lab10.java:47)

Heres my .txt file
100
200
bogus
300
150
weasel
400
600
250
3.5
800
50
500
450
600
550

import java.util.*;
import java.io.*;
public class lab10
{
 
	public static void main(String [] args)
	{
		Scanner inScan;
		Scanner fScan = null;
		inScan = new Scanner (System.in);
		String nextItem;
		int nextInt = 0;
		int i = 0;
 
 
		int [] A = new int [5];
 
		boolean check = true; 
 
	while (check = true){
	      System.out.println("Please enter the file to read from: ");
		  String fName = inScan.nextLine();
 
 
 
 
 
 
		try {
 
 
			fScan = new Scanner (new File(fName));
 
			while (fScan.hasNextLine())
			{
 
				nextItem = fScan.nextLine(); // Stores first number into nextItem
 
 
				// nextLine READS STRINGS
	// something going on here.... ^ v reason for this
 
				// TAKES String and makes it INT!  
				nextInt = Integer.parseInt(nextItem);
 
 
 
 
 
 
				A[i] = nextInt; // array 
 
 
 
 
 
			    i++;  // increments the counter 
 
 
 
 
			   // System.out.println( " is not an integer -- ignored");
 
            }
 
 
 
 
 
 
 
			System.out.println("Here are your " + i + " items:");
			for (int j = 0; j < i; j++)
			{
				System.out.println(A[j] + " ");
 
			}
 
 
 
		} catch (FileNotFoundException e) {
 
			System.out.println("Your file is invalid ");
 
 
 
 
 
		}
 
 
 
	}// end while
 
 
	}
 
}

You are trying to convert each line of the file into an integer,

nextInt = Integer.parseInt(nextItem);

So when you hit a text string containing non numeric characters you are going to have a problem. The method parseInt() throws an exception NumberFormatException when it tries to parse a string that contains non numeric data, you need to find a way of handling this. Either use a try/catch block to catch the exception and deal with it appropriately or parse the strings yousrself beforehand to check if they are inetegers or not.

Integer (Java Platform SE 6)

Chris

nextItem = fScan.nextLine(); // Stores first number into nextItem


// nextLine READS STRINGS
// something going on here.... ^ v reason for this

// TAKES String and makes it INT!
nextInt = Integer.parseInt(nextItem);

You could just have

int x = fScan.nextInt();

However, bogus is a String.

How can you turn it into an int?