Reading and Writing .wav Files in Java

Question

I'm interested in learning about audio file manipulation in Java, so, after researching some background on the .wav file format, I wrote a simple program to read in a .wav file, place it into a byte array, and then write that array to a new .wav file. The output file isn't a copy of the input file, however. For example, when I open the two .wav files in a text editor (Notepad++), the original will begin by saying "RIFF" as it should, but the copy starts out with a series of null characters. Can anybody tell me what I'm doing wrong?

Here is my code:

package funwithwavs2;

import javax.sound.sampled.*;
import java.io.*;

public class FunWithWavs2 {

public static void main(String[] args) {
    int x;
    byte[] wavBytes=new byte[100000000];

    try {
        AudioInputStream ais=AudioSystem.getAudioInputStream(new File("Centerfold.wav"));


        while((x=ais.read(wavBytes))>0) {
            System.out.println("X: "+x);
        }

        writeToFile(wavBytes);
    }
    catch (Exception ex) {
        System.err.println("Error reading WAV file.");
        ex.printStackTrace();
    }

}


public static void writeToFile(byte[] b) {
    File file=new File ("centerfold3.wav");
    try {
        if(!file.exists()) {
            file.createNewFile();
        }

        FileWriter fw=new FileWriter(file.getAbsoluteFile());
        BufferedWriter bw=new BufferedWriter(fw);
        for(int i=0;i<b.length;i++) {
            bw.write(b[i]);
        }
        bw.close();
    } catch (IOException e) {
        e.printStackTrace();
    }
}

}

Thanks!

Edit to Reflect Comments Below: I switched my input declaration to the the code snippet below, but it gives me a mark/reset not supported exception.

InputStream input=new FileInputStream("Centerfold.wav");
        AudioInputStream ais=AudioSystem.getAudioInputStream(input);

The crux of my issue isn't writing to the output .wav file. It's that the bytes that I read from the input file aren't what I expect them to be.

while((x2=ais.read(wavBytes))>0) {
            System.out.println("X2: "+x2);
        }


        for(int i=0;i<36;i++) {
            System.out.println(i+": "+wavBytes[i]);
        }

Looking at this code, I would expect the first four characters that are printed out to be the ASCII values for: R I F F, per the .wav file format. What I get, however, is a series of 0s, the ASCII value for a NULL. Why is there this discrepancy? Am I fundamentally misunderstanding something about either the .wav file format or the functionality of the javax.sound.sampled classes?

Does it have something to do with `FileWriter`? You read the file with AudioInputStream... maybe there is a special AudioOutputStream?... edit* does the output .wav file still play even though it has different header? — j.con, Oct 24 '14 at 19:07
No. I've also printed out the byte array to the console. That yields the same output as the file (which is to say, different from the original wav). Edit: The output audio file doesn't play at all. Something else that's interesting: the original file is 37MB. The output one is 135MB. — Andrew Kline, Oct 24 '14 at 19:08
Ok... I think you need `FileInputStream` instead of `File` on this line `AudioInputStream ais=AudioSystem.getAudioInputStream(new File("Centerfold.wav"));` — j.con, Oct 24 '14 at 19:11
Ehh disregard my posts... this link should help you http://stackoverflow.com/questions/3297749/java-reading-manipulating-and-writing-wav-files — j.con, Oct 24 '14 at 19:13
`AudioInputStream` just gives you the decoded audio bytes from a file, headers and other non-audio components of the file are not returned. — greg-449, Oct 24 '14 at 19:52

Reading and Writing .wav Files in Java

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