Example - Read a Text File


import java.io.BufferedReader;
import java.io.IOException;
import java.io.FileNotFoundException;
import java.io.FileReader;

public class FileRead
{
    public static void main(String[] args)
    {
        String instr;
        try
        {

//  use 1st command line argument as file name
            FileReader fin = new FileReader(args[0]);
            BufferedReader filein = new BufferedReader(fin);

//  read each line of file into a String and print the string
//  readLine returns null at end of file
            instr = filein.readLine();
            while (instr != null) {
                System.out.println(instr);
                instr = filein.readLine();
            }
            filein.close();
        }
        catch(FileNotFoundException e) {
            System.out.println("Error: file " + args[0] + " not found");
        }
        catch(IOException e) {}
    }
}


Input File:
C:\cafe1.8\Mine>type fileread.in
first line of file
here is the second line
next are some numbers
33 44 55 66
last line

Output:
C:\cafe1.8\Mine>java FileRead fileread.in
first line of file
here is the second line
next are some numbers
33 44 55 66
last line

C:\cafe1.8\Mine>java FileRead another
Error: file another not found


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