Server drives me crazy !

Question about the task

Writing to an existing file

Java Collections, Level 2, Lesson 2

Under discussion

It works locally. I don't understand what is the problem with this server?

The main() method accepts three arguments:
1) fileName - the path to a file;
2) number - a position in the file;
3) text - the text.
Write text to the fileName file starting at the position indicated by number.
The write operation must overwrite the old data in the file.
If the file is too short, then begin writing at the end of the file.
Use RandomAccessFile and its seek() and write() methods.

Requirements:

You must use RandomAccessFile in the Solution class's main() method.
In the Solution class's main() method, the program must write data to the file using the RandomAccessFile class's write() method.
The write operation must start at the specified position and replace the contents.
If the file is too short, then you must write text at the end of the file.

package com.codegym.task.task32.task3201; import java.io.IOException; import java.io.RandomAccessFile; /* Writing to an existing file */ public class Solution { public static void main(String... args) throws IOException { String fileName = args[0]; long number = Long.parseLong(args[1]); String text = args[2]; RandomAccessFile raf = new RandomAccessFile(fileName,"rw"); long len = raf.length(); long seekNumber = number < len ? number : len ; raf.seek(seekNumber); raf.writeBytes(text); raf.close(); } }

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Jakub Raczkowski

Level 41 , Polska, Poland

21 November 2023, 02:11

If the file is too short, then begin writing at the end of the file. This part is misleading. It's not the full file, but the rest of the file, starting from the given position (args[1]). So the correct if statement should look like this:

if (textLength + Long.parseLong(args[1]) > fileLength)

Darek

Level 41 , Katowice, Poland

22 July 2020, 12:24

I had similar problems. 1. In if you need to compare the length of the file to the length of the text - cursor position All text must fit in an existing file, then you put the text in the given position Otherwise, you append to the end of the file for example. if (lenFile> text.length () + numPos) { raf.seek (numPos); } else { raf.seek (lenFile); } 2. Guadalupe is right. I also misread the instruction. For this task, you must use write (), not writeBites. That's why you have to change here for example. raf.write (text.getBytes ());

Jonas

Level 41 , Vilnius, Lithuania

18 March 2020, 12:33

Convert your "text" string to byte array using text.getBytes() and then output the byte array

Guadalupe Gagnon

Level 37 , Tampa, United States

10 December 2019, 17:59

"RandomAccessFile class's write() method." Line 20 uses the wrong method: .writeBytes()