FileUtils.java

FileUtils.java

public class FileUtils {
    public static void joinFiles(File destination, File[] sources) throws IOException {
        OutputStream output = null;
        try {
            output = createAppendableStream(destination);
            for (File source : sources) {
                appendFile(output, source);
            }
        } finally {
            IOUtils.closeQuietly(output);
        }
    }

    private static BufferedOutputStream createAppendableStream(File destination) throws FileNotFoundException {
        return new BufferedOutputStream(new FileOutputStream(destination, true));
    }

    private static void appendFile(OutputStream output, File source) throws IOException {
        InputStream input = null;
        try {
            input = new BufferedInputStream(new FileInputStream(source));
            IOUtils.copy(input, output);
        } finally {
            IOUtils.closeQuietly(input);
        }
    }
}

reference

• https://stackoverflow.com/questions/14673063/merging-multiple-files-in-java/14673198#14673198