异常信息

java.io.FileNotFoundException: Invalid file path
    at java.io.FileOutputStream.<init>(FileOutputStream.java:206)
    at java.io.FileOutputStream.<init>(FileOutputStream.java:162)
    at com.crazymakercircle.iodemo.socketDemos.NioReceiveServer.processData(NioReceiveServer.java:148)
    at com.crazymakercircle.iodemo.socketDemos.NioReceiveServer.startServer(NioReceiveServer.java:101)
    at com.crazymakercircle.iodemo.socketDemos.NioReceiveServer.main(NioReceiveServer.java:194)
     * 处理客户端传输过来的数据
    private void processData(SelectionKey key) throws IOException {
        Client client = clientMap.get(key.channel());
        SocketChannel socketChannel = (SocketChannel) key.channel();
        int num = 0;
        try {
            buffer.clear();
            while ((num = socketChannel.read(buffer)) > 0) {
                buffer.flip();
                //客户端发送过来的，首先是文件名
                if (null == client.fileName) {
                    // 文件名
                    String fileName = charset.decode(buffer).toString();
                    String destPath = IOUtil.getResourcePath(NioDemoConfig.SOCKET_RECEIVE_PATH);
                    File directory = new File(destPath);
                    if (!directory.exists()) {
                        directory.mkdir();
                    client.fileName = fileName;
                    String fullName = directory.getAbsolutePath()
                            + File.separatorChar + fileName;
                    Logger.debug("NIO  传输目标文件：" + fullName);
                    File file = new File(fullName);
                    FileChannel fileChannel = new FileOutputStream(file).getChannel();
                    client.outChannel = fileChannel;
                //客户端发送过来的，其次是文件长度
                else if (0 == client.fileLength) {
                    // 文件长度
                    long fileLength = buffer.getLong();
                    client.fileLength = fileLength;
                    client.startTime = System.currentTimeMillis();
                    Logger.debug("NIO  传输开始：");
                //客户端发送过来的，最后是文件内容
                else {
                    // 写入文件
                    client.outChannel.write(buffer);
                buffer.clear();
            key.cancel();
        } catch (IOException e) {
            key.cancel();
            e.printStackTrace();
            return;
        // 调用close为-1 到达末尾
        if (num == -1) {
            IOUtil.closeQuietly(client.outChannel);
            System.out.println("上传完毕");
            key.cancel();
            Logger.debug("文件接收成功,File Name：" + client.fileName);
            Logger.debug(" Size：" + IOUtil.getFormatFileSize(client.fileLength));
            long endTime = System.currentTimeMillis();
            Logger.debug("NIO IO 传输毫秒数：" + (endTime - client.startTime));
 File file = new File(fullName);
创建了一个File对象，但是fullName代表的文件必须存在。但是根据代码业务逻辑。复制文件时，新文件一般是不存在的，所以必须手动新建文件。
                    File file = new File(fullName);
//                    文件不存在则创建文件
                    if (!file.exists()){
                        try {
                            file.createNewFile();
                        } catch (IOException e) {
                            e.printStackTrace();
这段代码的意思是，创建一个名为file的File对象，如果该文件不存在，则手动创建，再次运行，则此异常消失。
     * 处理客户端传输过来的数据
    private void processData(SelectionKey key) throws IOException {
        Client client = clientMap.get(key.channel());
        SocketChannel socketChannel = (SocketChannel) key.channel();
        int num = 0;
        try {
            buffer.clear();
            while ((num = socketChannel.read(buffer)) > 0) {
                buffer.flip();
                //客户端发送过来的，首先是文件名
                if (null == client.fileName) {
                    // 文件名
                    String fileName = charset.decode(buffer).toString();
                    String destPath = IOUtil.getResourcePath(NioDemoConfig.SOCKET_RECEIVE_PATH);
                    File directory = new File(destPath);
                    if (!directory.exists()) {
                        directory.mkdir();
                    client.fileName = fileName;
                    String fullName = directory.getAbsolutePath()
                            + File.separatorChar + fileName;
                    Logger.debug("NIO  传输目标文件：" + fullName);
                    File file = new File(fullName);
//                    文件不存在则创建文件
                    if (!file.exists()){
                        try {
                            file.createNewFile();
                        } catch (IOException e) {
                            e.printStackTrace();
                    FileChannel fileChannel = new FileOutputStream(file).getChannel();
                    client.outChannel = fileChannel;
                //客户端发送过来的，其次是文件长度
                else if (0 == client.fileLength) {
                    // 文件长度
                    long fileLength = buffer.getLong();
                    client.fileLength = fileLength;
                    client.startTime = System.currentTimeMillis();
                    Logger.debug("NIO  传输开始：");
                //客户端发送过来的，最后是文件内容
                else {
                    // 写入文件
                    client.outChannel.write(buffer);
                buffer.clear();
            key.cancel();
        } catch (IOException e) {
            key.cancel();
            e.printStackTrace();
            return;
        // 调用close为-1 到达末尾
        if (num == -1) {
            IOUtil.closeQuietly(client.outChannel);
            System.out.println("上传完毕");
            key.cancel();
            Logger.debug("文件接收成功,File Name：" + client.fileName);
            Logger.debug(" Size：" + IOUtil.getFormatFileSize(client.fileLength));
            long endTime = System.currentTimeMillis();
            Logger.debug("NIO IO 传输毫秒数：" + (endTime - client.startTime));