Reputation: 7076
I've got a program where I need to generate an integer, write it to a text file and read it back the next time the program runs. After some anomalous behavior, I've stripped it down to setting an integer value, writing it to a file and reading it back for debugging.
totScore
, is set to 25 and when I print to the console prior to writing to the file, I see a value of 25
. However, when I read the file and print to the console I get three values...25
, 13
, and 10
. Viewing the text file in notepad gives me a character not on the keyboard, so I suspect that the file is being stored in something other that int
.
Why do I get different results from my write and read steps?
Is it not being written as an int
? How are these values being stored in the file? Do I need to cast the read value as something else and convert it to an integer?
Consider:
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.nio.file.*;
import java.nio.file.StandardOpenOption.*;
//
public class HedgeScore {
public static void main(String[] args) {
int totScore = 25;
OutputStream outStream = null; ///write
try {
System.out.println("totscore="+totScore);
BufferedWriter bw = new BufferedWriter(new FileWriter(new File("hedgescore.txt")));
bw.write(totScore);
bw.write(System.getProperty("line.separator"));
bw.flush();
bw.close();
}
catch(IOException f) {
System.out.println(f.getMessage());
}
try {
InputStream input = new FileInputStream("hedgescore.txt");
int data = input.read();
while(data != -1) {
System.out.println("data being read from file :"+ data);
data = input.read();
int prevScore = data;
}
input.close();
}
catch(IOException f) {
System.out.println(f.getMessage());
}
}
}
Upvotes: 1
Views: 504
Reputation: 285405
You're reading/writing Strings and raw data, but not being consistent. Why not instead read in Strings (using a Reader of some sort) and then convert to int by parsing the String? Either that or write out your data as bytes and read it in as bytes -- although that can get quite tricky if the file must deal with different types of data.
So either:
import java.io.*;
public class HedgeScore {
private static final String FILE_PATH = "hedgescore.txt";
public static void main(String[] args) {
int totScore = 25;
BufferedWriter bw = null;
try {
System.out.println("totscore=" + totScore);
bw = new BufferedWriter(new FileWriter(new File(
FILE_PATH)));
bw.write(totScore);
bw.write(System.getProperty("line.separator"));
bw.flush();
} catch (IOException f) {
System.out.println(f.getMessage());
} finally {
if (bw != null) {
try {
bw.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
InputStream input = null;
try {
input = new FileInputStream(FILE_PATH);
int data = 0;
while ((data = input.read()) != -1) {
System.out.println("data being read from file :" + data);
}
input.close();
} catch (IOException f) {
System.out.println(f.getMessage());
} finally {
if (input != null) {
try {
input.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
or:
import java.io.*;
public class HedgeScore2 {
private static final String FILE_PATH = "hedgescore.txt";
public static void main(String[] args) {
int totScore = 25;
PrintWriter pw = null;
try {
System.out.println("totscore=" + totScore);
pw = new PrintWriter(new FileWriter(new File(FILE_PATH)));
pw.write(String.valueOf(totScore));
pw.write(System.getProperty("line.separator"));
pw.flush();
} catch (IOException f) {
System.out.println(f.getMessage());
} finally {
if (pw != null) {
pw.close();
}
}
BufferedReader reader = null;
try {
reader = new BufferedReader(new FileReader(FILE_PATH));
String line = null;
while ((line = reader.readLine()) != null) {
System.out.println(line);
}
} catch (IOException f) {
System.out.println(f.getMessage());
} finally {
if (reader != null) {
try {
reader.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
}
Upvotes: 4