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Where am I going wrong? public class Solution { public static void main(String[] args)throws IOException { //Read a file name three times from the console BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String file1 = reader.readLine(); String file2 = reader.readLine(); String file3 = reader.readLine(); //Use FileInputStream to read from a file FileInputStream inputStream = new FileInputStream(file1); byte[]buffer = new byte[inputStream.available()]; while(inputStream.available() > 0){ inputStream.read(buffer); } //Use FileOutputStream to write to files FileOutputStream outputStream2 = new FileOutputStream(file2); FileOutputStream outputStream3 = new FileOutputStream(file3); int bottomHalf = 0; int topHalf = 0; if(buffer.length % 2 != 0){ bottomHalf = (buffer.length + 1)/2 ; topHalf = bottomHalf + 1; //The first half of the bytes in the first file must be written to the second file outputStream2.write(buffer,0,bottomHalf); //The second half of the bytes in the first file must be written to the third file outputStream3.write(buffer, topHalf,buffer.length -1); } else{ //The first half of the bytes in the first file must be written to the second file outputStream2.write(buffer,0,buffer.length/2 ); //The second half of the bytes in the first file must be written to the third file outputStream3.write(buffer,buffer.length/2 + 1,buffer.length -1); } //FileInputStream and FileOutputStream must be closed inputStream.close(); outputStream2.close(); outputStream3.close(); } }

Read 3 file names from the console: file1, file2, file3.
Split file1 as follows:
Write the first half of its bytes to file2,and write the second half of its bytes to file3.
If the number of bytes in file1 is odd, then file2 should contain the larger half.
Close the streams.

Requirements:

The program should read a file name three times from the console.
Use FileInputStream to read from a file, and use FileOutputStream to write to files.
The first half of the bytes in the first file must be written to the second file.
The second half of the bytes in the first file must be written to the third file.
The FileInputStream and FileOutputStream must be closed.

package com.codegym.task.task18.task1808; /* Splitting a file */ import java.io.*; public class Solution { public static void main(String[] args)throws IOException { //Read a file name three times from the console BufferedReader reader = new BufferedReader(new InputStreamReader(System.in)); String file1 = reader.readLine(); String file2 = reader.readLine(); String file3 = reader.readLine(); //Use FileInputStream to read from a file FileInputStream inputStream = new FileInputStream(file1); byte[]buffer = new byte[inputStream.available()]; while(inputStream.available() > 0){ inputStream.read(buffer); } //Use FileOutputStream to write to files FileOutputStream outputStream2 = new FileOutputStream(file2); FileOutputStream outputStream3 = new FileOutputStream(file3); int bottomHalf = 0; int topHalf = 0; if(buffer.length % 2 != 0){ bottomHalf = (buffer.length + 1)/2 ; topHalf = bottomHalf + 1; //The first half of the bytes in the first file must be written to the second file outputStream2.write(buffer,0,bottomHalf); //The second half of the bytes in the first file must be written to the third file outputStream3.write(buffer, topHalf,buffer.length -1); } else{ //The first half of the bytes in the first file must be written to the second file outputStream2.write(buffer,0,buffer.length/2 ); //The second half of the bytes in the first file must be written to the third file outputStream3.write(buffer,buffer.length/2 + 1,buffer.length -1); } //FileInputStream and FileOutputStream must be closed inputStream.close(); outputStream2.close(); outputStream3.close(); } }

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Nouser

Level 36 , Germany

6 May 2020, 07:00

When using write the start index ins inclusive, then follows the number of bytes you want to write, not the end index (unlike substring). So as third parameter for the write command buffer.length is twice of what you want to save to file. You could do it as follows:

int end, mid;
mid = end = buffer.length / 2;
if (buffer.length % 2 != 0) mid++;
outputStream2.write(buffer,0,mid);
outputStream3.write(buffer,mid,end);

Ntuthuko Xaba

Level 18 , Johannesburg, South Africa

8 May 2020, 19:50

tnx but i tried that and its still not working

Ntuthuko Xaba

Level 18 , Johannesburg, South Africa

5 May 2020, 18:18

I'm getting the 3rd and 4th requirements wrong.

Nouser

Level 36 , Germany

9 May 2020, 06:49

solution

My entire solution... worked for me

public static void main(String[] args) {
    String fileName1 = null, fileName2 = null, fileName3 = null;
    try(BufferedReader reader = new BufferedReader(new InputStreamReader(System.in))) {
        fileName1 = reader.readLine();
        fileName2 = reader.readLine();
        fileName3 = reader.readLine();
    } catch(IOException e) {
        e.printStackTrace();
    }
    //input stream, auto closes after try block
    try (   FileInputStream in = new FileInputStream(fileName1);
            FileOutputStream out2 = new FileOutputStream(fileName2);
            FileOutputStream out3 = new FileOutputStream(fileName3)) {
        //how long in bytes is the file to read
        int fileLength = in.available();
        //the file length, file 2 and 3 should have
        int toWrite2, toWrite3;
        //the number of bytes to save in file 2 and 3 are file1 / 2
        toWrite2 = toWrite3 = fileLength / 2;
        //if filelength file1 is odd, then add 1 byte to file2 (that byte falls out due to division)
        if (fileLength % 2 != 0)
            toWrite2++;

        //define a byte array with file1 length
        byte[] data = new byte[fileLength];
        in.read(data, 0, fileLength);
        //write the data 0-toRead2 and toRead2-toRead3
        out2.write(data, 0, toWrite2);
        out3.write(data, toWrite2, toWrite3);

    } catch (FileNotFoundException e) {
        e.printStackTrace();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

Ntuthuko Xaba

Level 18 , Johannesburg, South Africa

10 May 2020, 18:59

When I follow your example it's wrong so I ended up , copying and pasting your solution, I still don't understand why it was wrong though.