java - 套接字编程Java : How to receive multiple files from outputstream?

Question

我的服务器正在向我的客户端发送多个文件。然而在客户端，它只接收第一个文件，因为我不知道如何迭代并获取第二个文件。

服务器发送如下:

ListIterator iter = missingfiles.listIterator(); 
                    //missingfiles contain all the filenames to be sent
String filename;
while (iter.hasNext()) {
    // System.out.println(iter.next());
    filename=(String) iter.next();
    File myFile = new File("src/ee4210/files/"+filename); 
    byte[] mybytearray = new byte[(int) myFile.length()];  

    FileInputStream fis = new FileInputStream(myFile);  
    BufferedInputStream bis = new BufferedInputStream(fis);  
    //bis.read(mybytearray, 0, mybytearray.length);  

    DataInputStream dis = new DataInputStream(bis);     
    dis.readFully(mybytearray, 0, mybytearray.length);  

    OutputStream os = _socket.getOutputStream();  

    //Sending file name and file size to the server  
    DataOutputStream dos = new DataOutputStream(os);     
    dos.writeUTF(myFile.getName());     
    dos.writeLong(mybytearray.length);     
    dos.write(mybytearray, 0, mybytearray.length);     
    dos.flush(); 
}

客户端接收是这样的:(它只会接收第一个文件，我不知道如何让它循环接收下一个文件)

int bytesRead;
int current = 0;
int filecount = 0;
InputStream in;
try {
    in = _socket.getInputStream();
    DataInputStream clientData = new DataInputStream(in);
        String fileName = clientData.readUTF();
        OutputStream output = new FileOutputStream(
                               "src/ee4210/files/"+ fileName);
        long size = clientData.readLong();
        byte[] buffer = new byte[1024];
        while (size > 0
                && (bytesRead = clientData.read(buffer, 0,
                        (int) Math.min(buffer.length, size))) != -1) {
            output.write(buffer, 0, bytesRead);
            size -= bytesRead;
        }
} catch (IOException e) {
    // TODO Auto-generated catch block
    e.printStackTrace();
}

Answer 1

How to receive multiple files from outputstream?

显而易见的答案是“一次一个，并提供额外信息来告诉您一个在哪里停止，另一个从哪里开始”。最常用的技术是在文件之前发送文件大小，例如通过 DataOutputStream.writeLong() 作为 long，并在接收器处更改读取循环以在恰好那么多字节后停止，关闭输出文件，并继续读取下一个 long 或 end 的外部循环-of-stream。