Read/Write program help

Azzy · **Posted:** Tue Nov 02, 2004 9:33 am

I need help with this read write program that i need help with. The writing to a file part is not working on it so please help.

code:

import java.io.*;
import java.text.*;

public class ReadWrite
{
public static void main (String[] args)throws Exception
{
DataInput keyboard = new DataInputStream(System.in);
String temp;
char response;

PrintStream out;
BufferedReader in;
String fileName;
String fileContents;
String readOrWrite;
String cont;

readWriteExitLoop:
while (true)
{
System.out.println("'Read', 'Write' or 'Exit'");
readOrWrite = keyboard.readLine();

if (readOrWrite.equalsIgnoreCase("read"))
{
System.out.println("Please enter the file to read from?");
fileName = keyboard.readLine();
in = new BufferedReader(new FileReader(fileName));
fileContents = in.readLine();
System.out.println(fileContents);
System.out.print("\n\nPress any key to continue.");
cont = keyboard.readLine();
}
else if (readOrWrite.equalsIgnoreCase("write"))
{
System.out.println("Please enter the file to write to?");
fileName = keyboard.readLine();
out = System.out;
System.out.println("Please type what you want to be writen");
fileContents = keyboard.readLine();
out.println(fileContents);
System.out.print("\n\nPress any key to continue.");
cont = keyboard.readLine();
}
else if (readOrWrite.equalsIgnoreCase("exit"))
{
break readWriteExitLoop;
}
else
{
System.out.println("Improper input.");
System.out.print("\n\nPress any key to continue.");
cont = keyboard.readLine();
}
readOrWrite = ("");
cont = ("");
System.out.print("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n");
}

System.out.println("");
System.out.println("");
System.out.print("Hit 'Enter' to end...");
response = (char)System.in.read();
}
}

wtd · **Posted:** Tue Nov 02, 2004 2:13 pm

Your problem is that you were never opening a new PrintStream pointed at the output file. You were just setting "out" to "System.out", so "out.println" just went to the console.

Cleaned up:

code:

import java.io.*;
import java.text.*;

public class ReadWrite
{
private static BufferedReader keyboard = new BufferedReader(
new InputStreamReader(System.in));

public static void main (String[] args) throws Exception
{
readWriteExitLoop:

while (true)
{
System.out.println("'Read', 'Write' or 'Exit'");
String choice = keyboard.readLine();

if (readOrWrite.equalsIgnoreCase("read"))
{
System.out.println("Please enter the file to read from?");
String fileName = keyboard.readLine();

BufferedReader inputFile = new BufferedReader(new FileReader(fileName));
String fileContents = inputFile.readLine();

System.out.println(fileContents);

pause("Press any key to continue.");
}
else if (readOrWrite.equalsIgnoreCase("write"))
{
System.out.println("Please enter the file to write to?");
String fileName = keyboard.readLine();
PrintStream outputFile = new PrintStream(fileName);

System.out.println("Please type what you want to be writen");
String fileContents = keyboard.readLine();
outputFile.println(fileContents);

pause("Press any key to continue.");
}
else if (readOrWrite.equalsIgnoreCase("exit"))
{
break readWriteExitLoop;
}
else
{
System.out.println("Improper input.");
pause("Press any key to continue.");
}

/* This is so silly. Attempting to clear the
   * screen this way should not be done. You can't
   * control the output terminal, so don't try.
   * readOrWrite = ("");
   * cont = ("");
   * System.out.print("\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n\n");
   */
}

pause("Hit 'Enter' to end...");
}

private static void pause(String message)
{
System.out.println("\n\n" + message);
keyboard.readLine();
}
}

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