NullPointerException

[Lio Liov]

I have null pointer exception and My code ,could you help fixing it
Thanks

import java.io.*;
import java.util.*;

public class FileReader {
	String fileToOpen;

	public FileReader(String openFile) {
		fileToOpen = "jobs/" + openFile + ".txt";
	}

	private Scanner x;

	public void openFile() {
		try {
			x = new Scanner(new File(fileToOpen));
		} catch (Exception e) {
			System.out.println("Could not find the job");
		}
	}

	public String[] readFile() {
		String[] values = null;
		int i = 0;
		try {
			while (x.hasNext()) {
				String line = x.nextLine();
				String edno = line.substring(line.indexOf(':') + 1);
				values[i] = edno;
				i++;
			}

		} catch (Exception e) {
		}
		return values;
	}

	public static void main(String[] args) {

		String job = "SecondJob";
		FileReader inp = new FileReader(job);
		inp.openFile();
		System.out.println(inp.readFile().length);
	}
}

[Koen Aerts]

Stacktrace would help.

[dennis deems]

The String array is never instantiated. It is explicitly set to null, and is still null when you try to write a String to one of its indices.

[Lio Liov]

Thanks ,can I instantiate the array without specified the size

[Stefaan Dutry]

Lio Liov wrote:can I instantiate the array without specified the size

I would suggest looking at, and using ArrayList.
Especialy it's add method and it's toArray method.

Although i can't think of a reason to convert it to an Array again in this case.