复制Mp3文件

Question

I am trying to create a application that allows me to copy mp3 and mp4 files from one directory to another I am using file chooser and a factory pattern. The file seems to copy to the location but won't play. The new file is 8k while the original mp3 is 8mb so I guess It never copied the content, just created the file.

Here is my Mp3Factory class:

package application;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.logging.Logger;

import javax.swing.JFileChooser;
import javax.swing.filechooser.FileNameExtensionFilter;


import javafx.scene.media.Media;

public class Mp3Factory extends MediaFactory{

    private File folder = null;
    private File file= null;
    private Media m = null;

    FileOutputStream output = null;

    @Override
    public File openFile() {
        //Add image filter to file chooser
        fc.addChoosableFileFilter(new FileNameExtensionFilter("Mp3 Files", "mp3"));
        fc.setAcceptAllFileFilterUsed(false);

        //Show the file chooser dialog 
        int returnVal = fc.showOpenDialog(null);

        //If the user chose a file then return it 
        if (returnVal == JFileChooser.APPROVE_OPTION) {
            return fc.getSelectedFile();
        } else {
            System.out.println("Open command cancelled by user.");
            return null;
        }
    }

    @Override
    public void saveFile(File file) {
        String fileName = file.getName();
        folder = new File("H:\\TestFolder\\"); //output file path

        if (!folder.exists()) {
            try {
                folder.createNewFile();
            } catch (IOException ex) {
                ex.printStackTrace();
            }
        }

        try{
            String folder_location = folder.toString() + "\\";
            file = new File(folder_location + fileName.toString());
            output = new FileOutputStream(file);

            if (!file.exists()) {
                file.createNewFile();
            }

            byte[] buffer = new byte[4096];

            output.write(buffer);
            output.flush();
            output.close();
        }catch (Exception e) {
            e.printStackTrace();
        }

    }

    @Override
    public void defaultSavePath() {
        // TODO Auto-generated method stub

    }

    @Override
    public void loaddefaultSavePath() {
        // TODO Auto-generated method stub

    }

}

Answer 1

Java already has a good copy function:

public void saveFile(File file) throw IOException {
    Path sourcePath = file.toPath();

    String fileName = file.getName();
    String targetPath = Paths.get("H:\\TestFolder", fileName);

    Files.copy(sourcePath, targetPath, StandardCopyOption.REPLACE_EXISTING);
}

Answer 2

package parse;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

public class CopySong {

    public static void main(String[] args) {InputStream inStream = null;
    OutputStream outStream = null;

    try{

        File source =new File("D:\\A.mp3");
        File dtn =new File("path\\A.mp3");

        inStream = new FileInputStream(source);
        outStream = new FileOutputStream(dtn);

        byte[] buffer = new byte[1024];

        int length;
        //copy the file content in bytes
        while ((length = inStream.read(buffer)) > 0){

            outStream.write(buffer, 0, length);

        }

        inStream.close();
        outStream.close();

        System.out.println("File is copied successful!");

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

}